June 25, 2010

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The main attempts to specify what makes a causal-informational state a mental representation are Asymmetric Dependency Theories (e.g., Fodor 1987, 1990, 1994) and Teleological Theories (Fodor 1990, Millikan 1984, Papineau 1987, Dretske 1988, 1995). The Asymmetric Dependency Theory distinguishes merely informational relations from representational relations on the basis of their higher-order relations to each other: informational relations depend upon representational relations, but not vice-versa. For example, if tokens of a mental state type are reliably caused by horses, cows-on-dark-nights, zebras-in-the-mist and Great Danes, then they carry information about horses, etc. If, however, such tokens are caused by cows-on-dark-nights, etc. because they were caused by horses, but not vice versa, then they represent horses.


According to Teleological Theories, representational relations are those a representation-producing mechanism has the selected (by evolution or learning) function of establishing. For example, zebra-caused horse-representations do not mean zebra, because the mechanism by which such tokens are produced has the selected function of indicating horses, not zebras. The horse-representation-producing mechanism that responds to zebras is malfunctioning.

Functional theories (Block 1986, Harman 1973), hold that the content of a mental representation is grounded in its (causal computational, inferential) relations to other mental representations. They differ on whether relata should include all other mental representations or only some of them, and on whether to include external states of affairs. The view that the content of a mental representation is determined by its inferential/computational relations with all other representations is holism; the view it is determined by relations to only some other mental states is localism (or molecularism). (The view that the content of a mental state depends on none of its relations to other mental states is atomism.) Functional theories that recognize no content-determining external relata have been called solipsistic (Harman 1987). Some theorists posit distinct roles for internal and external connections, the former determining semantic properties analogous to sense, the latter determining semantic properties analogous to reference (McGinn 1982, Sterelny 1989)

[Reductive] representationalists (Dretske, Lycan, Tye), usually take one or another of these theories to provide an explanation of the (Non-conceptual) content of experiential states. They thus tend to be Externalists about phenomenological as well as conceptual content. Phenomenalists and non-deductive representationalists (Block, Chalmers, Loar, Peacocke, Siewert), on the other hand, take it that the representational content of such states is (at least in part) determined by their intrinsic phenomenal properties. Further, those who advocate a phenomenology-based approach to conceptual content (Horgan and Tiensen, Loar, Pitt, Searle, Siewert) also seem to be committed to internalist individuation of the content (if not the reference) of such states.

Generally, those who, like informational theorists, think relations to one's (natural or social) environment are (at least partially) determinative of the content of mental representations are Externalists, whereas of those who, like some proponents of functional theories, think contentually representative, if only to be determined by an individual's intrinsic properties alone, are internalists (or individualists).

This issue is widely taken to be of central importance, since psychological explanation, whether commonsense or scientific, is supposed to be both causal and content-based. (Beliefs and desires cause the behaviours they do because they have the contents they do. For example, the desire that one have a beer and the beliefs that there is beer in the refrigerator and that the refrigerator is in the kitchen may explain one's getting up and going to the kitchen.) If, however, a mental representation's having a particular content is due to factors extrinsic to it, it is unclear how its having that content could determine its causal powers, which, arguably, must be intrinsic. Some who accept the standard arguments for externalism have argued that internal factors determine a component of the content of a mental representation. They say that mental representations have both ‘narrow’ content (determined by intrinsic factors) and ‘wide’ or ‘broad’ content (determined by narrow content plus extrinsic factors). (This distinction may be applied to the sub-personal representations of cognitive science as well as to those of commonsense psychology.

Narrow content has been variously construed. Putnam (1975), Fodor (1982)), and Block (1986), for example, seem to understand it as something like de dicto content (i.e., Frégean sense, or perhaps character, à la Kaplan 1989). On this construal, narrow content is context-independent and directly expressible. Fodor (1987) and Block (1986), however, have also characterized narrow content as radically inexpressible. On this construal, narrow content is a kind of proto-content, or content-determinant, and can be specified only indirectly, via specifications of context/wide-content pairings. On both construal, narrow contents are characterized as functions from context to (wide) content. The narrow content of a representation is determined by properties intrinsic to it or its possessor such as its syntactic structure or its intra-mental computational or inferential role (or its phenomenology.

Burge (1986) has argued that causation-based worries about externalist individuation of psychological content, and the introduction of the narrow notion, are misguided. Fodor (1994, 1998) has more recently urged that a scientific psychology might not need narrow content in order to supply naturalistic (causal) explanations of human cognition and action, since the sorts of cases they were introduced to handle, viz., Twin-Earth cases and Frége cases, are nomologically either impossible or dismissible as exceptions to non-strict psychological laws.

The leading contemporary version of the Representational Theory of Mind, the Computational Theory of Mind, claims that the brain is a kind of computer and that mental processes are computations. According to the computational theory of mind, cognitive states are constituted by computational relations to mental representations of various kinds, and cognitive processes are sequences of such states. The computational theory of mind and the representational theory of mind, may by attempting to explain all psychological states and processes in terms of mental representation. In the course of constructing detailed empirical theories of human and animal cognition and developing models of cognitive processes’ implementable in artificial information processing systems, cognitive scientists have proposed a variety of types of mental representations. While some of these may be suited to be mental relata of commonsense psychological states, some - so-called ‘subpersonal’ or ‘sub-doxastic’ representations - are not. Though many philosophers believe that computational theory of mind can provide the best scientific explanations of cognition and behaviour, there is disagreement over whether such explanations will vindicate the commonsense psychological explanations of prescientific representational theory of mind.

According to Stich's (1983) Syntactic Theory of Mind, for example, computational theories of psychological states should concern themselves only with the formal properties of the objects those states are relations to. Commitment to the explanatory relevance of content, however, is for most cognitive scientists fundamental (Fodor 1981, Pylyshyn 1984, Von Eckardt 1993). That mental processes are computations, which computations are rule-governed sequences of semantically evaluable objects, and that the rules apply to the symbols in virtue of their content, are central tenets of mainstream cognitive science.

Explanations in cognitive science appeal to a many different kinds of mental representation, including, for example, the ‘mental models’ of Johnson-Laird 1983, the ‘retinal arrays,’ ‘primal sketches’ and ‘2½ -Dimensional sketches’ of Marr, 1982 ‘frames’ of Minsky 1974, the ‘sub-symbolic’ structures of Smolensky 1989, the ‘quasi-pictures’ of Kosslyn 1980, and the ‘interpreted symbol-filled arrays’ of Tye 1991 - in addition to representations that may be appropriate to the explanation of commonsense psychological states. Computational explanations have been offered of, among other mental phenomena, belief (Fodor 1975, Field 1978), visual perception (Marr 1982, Osherson, et al. 1990), rationality (Newell and Simon 1972, Fodor 1975, Johnson-Laird and Wason 1977), language learning and (Chomsky 1965, Pinker 1989), and musical comprehension (Lerdahl and Jackendoff 1983).

A fundamental disagreement among proponents of computational theory of mind concerns the realization of personal-level representations (e.g., thoughts) and processes (e.g., inferences) in the brain. The central debate here is between proponents of Classical Architectures and proponents of Conceptionist Architectures.

The classicists (e.g., Turing 1950, Fodor 1975, Fodor and Pylyshyn 1988, Marr 1982, Newell and Simon 1976) hold that mental representations are symbolic structures, which typically have semantically evolvable constituents, and that mental processes are rule-governed manipulations of them that are sensitive to their constituent structure. The conceptionists (e.g., McCulloch & Pitts 1943, Rumelhart 1989, Rumelhart and McClelland 1986, Smolensky 1988) hold that mental representations are realized by patterns of activation in a network of simple processors (‘nodes’) and that mental processes consist of the spreading activation of such patterns. The nodes themselves are, typically, not taken to be semantically evaluable; nor do the patterns have semantically evaluable constituents. (Though there are versions of Connectionism - ‘localist’ versions - on which individual nodes are taken to have semantic properties (e.g., Ballard 1986, Ballard & Hayes 1984).) It is arguable, however, that localist theories are neither definitive nor representative of the Conceptionist program (Smolensky 1988, 1991, Chalmers 1993).

Classicists are motivated (in part) by properties thought seems to share with language. Fodor's Language of Thought Hypothesis (LOTH) (Fodor 1975, 1987), according to which the system of mental symbols constituting the neural basis of thought is structured like a language, provides a well-worked-out version of the classical approach as applied to commonsense psychology. According to the language of thought hypotheses, the potential infinity of complex representational mental states is generated from a finite stock of primitive representational states, in accordance with recursive formation rules. This combinatorial structure accounts for the properties of productivity and systematicity of the system of mental representations. As in the case of symbolic languages, including natural languages (though Fodor does not suppose either that the language of thought hypothesis explains only linguistic capacities or that only verbal creatures have this sort of cognitive architecture), these properties of thought are explained by appeal to the content of the representational units and their combinability into contentful complexes. That is, the semantics of both language and thought is compositional: the content of a complex representation is determined by the contents of its constituents and their structural configuration.

Connectionists are motivated mainly by a consideration of the architecture of the brain, which apparently consists of layered networks of interconnected neurons. They argue that this sort of architecture is unsuited to carrying out classical serial computations. For one thing, processing in the brain is typically massively parallel. In addition, the elements whose manipulation drives computation in Conceptionist networks (principally, the connections between nodes) are neither semantically compositional nor semantically evaluable, as they are on the classical approach. This contrast with classical computationalism is often characterized by saying that representation is, with respect to computation, distributed as opposed to local: representation is local if it is computationally basic; and distributed if it is not. (Another way of putting this is to say that for classicists mental representations are computationally atomic, whereas for connectionists they are not.)

Moreover, connectionists argue that information processing as it occurs in Conceptionist networks more closely resembles some features of actual human cognitive functioning. For example, whereas on the classical view learning involves something like hypothesis formation and testing (Fodor 1981), on the Conceptionist model it is a matter of evolving distribution of ‘weight’ (strength) on the connections between nodes, and typically does not involve the formulation of hypotheses regarding the identity conditions for the objects of knowledge. The Conceptionist network is ‘trained up’ by repeated exposure to the objects it is to learn to distinguish; and, though networks typically require many more exposures to the objects than do humans, this seems to model at least one feature of this type of human learning quite well.

Further, degradation in the performance of such networks in response to damage is gradual, not sudden as in the case of a classical information processor, and hence more accurately models the loss of human cognitive function as it typically occurs in response to brain damage. It is also sometimes claimed that Conceptionist systems show the kind of flexibility in response to novel situations typical of human cognition - situations in which classical systems are relatively ‘brittle’ or ‘fragile.’

Some philosophers have maintained that Connectionism entails that there are no propositional attitudes. Ramsey, Stich and Garon (1990) have argued that if Conceptionist models of cognition are basically correct, then there are no discrete representational states as conceived in ordinary commonsense psychology and classical cognitive science. Others, however (e.g., Smolensky 1989), hold that certain types of higher-level patterns of activity in a neural network may be roughly identified with the representational states of commonsense psychology. Still others, argue that language-of-thought style representation is both necessary in general and realizable within Conceptionist architectures. (MacDonald & MacDonald 1995 collects the central contemporary papers in the classicist/Conceptionist debate, and provides useful introductory material as well.

Whereas Stich (1983) accepts that mental processes are computational, but denies that computations are sequences of mental representations, others accept the notion of mental representation, but deny that computational theory of mind provides the correct account of mental states and processes.

Van Gelder (1995) denies that psychological processes are computational. He argues that cognitive systems are dynamic, and that cognitive states are not relations to mental symbols, but quantifiable states of a complex system consisting of (in the case of human beings) a nervous system, a body and the environment in which they are embedded. Cognitive processes are not rule-governed sequences of discrete symbolic states, but continuous, evolving total states of dynamic systems determined by continuous, simultaneous and mutually determining states of the systems' components. Representation in a dynamic system is essentially information-theoretic, though the bearers of information are not symbols, but state variables or parameters.

Horst (1996), on the other hand, argues that though computational models may be useful in scientific psychology, they are of no help in achieving a philosophical understanding of the intentionality of commonsense mental states. computational theory of mind attempts to reduce the intentionality of such states to the intentionality of the mental symbols they are relations to. But, Horst claims, the relevant notion of symbolic content is essentially bound up with the notions of convention and intention. So the computational theory of mind involves itself in a vicious circularity: the very properties that are supposed to be reduced are (tacitly) appealed to in the reduction.

To say that a mental object has semantic properties is, paradigmatically, to say that it may be about, or be true or false of, an object or objects, or that it may be true or false simpliciter. Suppose I think that ocelots take snuff. I am thinking about my wish of placing a dot or period, if only to complete of this book, and if what I think of such an aspiring endeavour becomes is true, so, that, within its individualized participation, is then that my thought is true. According to representational theory of mind such states are to be explained as relations between agents and mental representations. To think that ocelots take snuff is to token in some way a mental representation whose content is that ocelots take snuff. On this view, the semantic properties of mental states are the semantic properties of the representations they are relations to.

Linguistic acts seem to share such properties with mental states. Suppose I say that ocelots take snuff. I am talking about ocelots, and if what I say of them (that they take snuff) is true of them, then my utterance is true. Now, to say that ocelots take snuff is (in part) to utter a sentence that means that ocelots take snuff. Many philosophers have thought that the semantic properties of linguistic expressions are inherited from the intentional mental states they are conventionally used to express. On this view, the semantic properties of linguistic expressions are the semantic properties of the representations that are the mental relata of the states they are conventionally used to express.

It is also widely held that in addition to having such properties as reference, truth-conditions and truth - so-called extensional properties - expressions of natural languages also have intensional properties, in virtue of expressing properties or propositions - i.e., in virtue of having meanings or senses, where two expressions may have the same reference, truth-conditions or truth value, yet express different properties or propositions (Frége 1892/1997). If the semantic properties of natural-language expressions are inherited from the thoughts and concepts they express (or vice versa, or both), then an analogous distinction may be appropriate for mental representations.

Søren Aabye Kierkegaard (1813-1855), a Danish religious philosopher, whose concern with individual existence, choice, and commitment profoundly influenced modern theology and philosophy, especially existentialism.

Søren Kierkegaard wrote of the paradoxes of Christianity and the faith required to reconcile them. In his book Fear and Trembling, Kierkegaard discusses Genesis 22, in which God commands Abraham to kill his only son, Isaac. Although God made an unreasonable and immoral demand, Abraham obeyed without trying to understand or justify it. Kierkegaard regards this ‘leap of faith’ as the essence of Christianity.

Kierkegaard was born in Copenhagen on May 15, 1813. His father was a wealthy merchant and strict Lutheran, whose gloomy, guilt-ridden piety and vivid imagination strongly influenced Kierkegaard. Kierkegaard studied theology and philosophy at the University of Copenhagen, where he encountered Hegelian philosophy and reacted strongly against it. While at the university, he ceased to practice Lutheranism and for a time led an extravagant social life, becoming a familiar figure in the theatrical and café society of Copenhagen. After his father's death in 1838, however, he decided to resume his theological studies. In 1840 he became engaged to the 17-year-old Regine Olson, but almost immediately he began to suspect that marriage was incompatible with his own brooding, complicated nature and his growing sense of a philosophical vocation. He abruptly broke off the engagement in 1841, but the episode took on great significance for him, and he repeatedly alluded to it in his books. At the same time, he realized that he did not want to become a Lutheran pastor. An inheritance from his father allowed him to devote himself entirely to writing, and in the remaining 14 years of his life he produced more than 20 books.

Kierkegaard's work is deliberately unsystematic and consists of essays, aphorisms, parables, fictional letters and diaries, and other literary forms. Many of his works were originally published under pseudonyms. He applied the term existential to his philosophy because he regarded philosophy as the expression of an intensely examined individual life, not as the construction of a monolithic system in the manner of the 19th-century German philosopher Georg Wilhelm Friedrich Hegel, whose work he attacked in Concluding Unscientific Postscript (1846: translations, 1941). Hegel claimed to have achieved a complete rational understanding of human life and history; Kierkegaard, on the other hand, stressed the ambiguity and paradoxical nature of the human situation. The fundamental problems of life, he contended, defy rational, objective explanation; the highest truth is subjective.

Kierkegaard maintained that systematic philosophy not only imposed a false perspective on human existence but that it also, by explaining life in terms of logical necessity, becomes a means of avoiding choice and responsibility. Individuals, he believed, create their own natures through their choices, which must be made in the absence of universal, objective standards. The validity of a choice can only be determined subjectively.

In his first major work, Either/Or, Kierkegaards described two spheres, or stages of existence, that the individual may choose: the aesthetic and the ethical. The aesthetic way of life is a refined hedonism, consisting of a search for pleasure and a cultivation of a mood. The aesthetic individual constantly seeks variety and novelty in an effort to stave off boredom but eventually must confront boredom and despair. The ethical way of life involves an intense, passionate commitment to duty, to unconditional social and religious obligations. In his later works, such as Stages on Life's Way (1845: Translations, 1940), Kierkegaard discerned in this submission to duty a loss of individual responsibility, and he proposed a third stage, the religious, in which one submits to the will of God but in doing so finds authentic freedom. In ‘Fear and Trembling’ (1846; Translated, 1941) Kierkegaard focused on God's command that Abraham sacrifice his son Isaac (Genesis 22: 1-19), an act that violates Abraham's ethical convictions. Abraham proves his faith by resolutely setting out to obey God's command, even though he cannot understand it. This ‘suspension of the ethical,’ as Kierkegaard called it, allows Abraham to achieve an authentic commitment to God. To avoid ultimate despair, the individual must make a similar ‘leap of faith’ into a religious life, which is inherently paradoxical, mysterious, and full of risk. One is called to it by the feeling of dread (The Concept of Dread, 1844; translations, 1944), which is ultimately a fear of nothingness.

Toward the end of his life Kierkegaard was involved in bitter controversies, especially with the established Danish Lutheran church, which he regarded as worldly and corrupt. His later works, such as The Sickness Unto Death (1849: translations, 1941), reflects an increasingly somber view of Christianity, emphasizing suffering as the essence of authentic faith. He also intensified his attack on modern European society, which he denounced in The Present Age (1846; translated 1940) for its lack of passion and for its quantitative values. The stress of his prolific writing and of the controversies in which he engaged gradually undermined his health; in October 1855 he fainted in the street, and he died in Copenhagen on November 11, 1855.

Kierkegaard's influence was at first confined to Scandinavia and to German-speaking Europe, where his work had a strong impact on Protestant Theology and on such writers as the 20th-century Austrian novelist Franz Kafka. As existentialism emerged as a general European movement after World War I, Kierkegaard's work was widely translated, and he was recognized as one of the seminal figures of modern culture.

Since scientists, during the nineteenth century were engrossed with uncovering the workings of external reality and seemingly knew of themselves that these virtually overflowing burdens of nothing, in that were about the physical substrates of human consciousness, the business of examining the distributive contribution in dynamic functionality and structural foundation of mind became the province of social scientists and humanists. Adolphe Quételet proposed a ‘social physics’ that could serve as the basis for a new discipline called sociology, and his contemporary Auguste Comte concluded that a true scientific understanding of the social reality was quite inevitable. Mind, in the view of these figures, was a separate and distinct mechanism subject to the lawful workings of a mechanical social reality.

More formal European philosophers, such as Immanuel Kant, sought to reconcile representations of external reality in mind with the motions of matter-based on the dictates of pure reason. This impulse was also apparent in the utilitarian ethics of Jerry Bentham and John Stuart Mill, in the historical materialism of Karl Marx and Friedrich Engels, and in the pragmatism of Charles Smith, William James and John Dewey. These thinkers were painfully aware, however, of the inability of reason to posit a self-consistent basis for bridging the gap between mind and matter, and each remains obliged to conclude that the realm of the mental exists only in the subjective reality of the individual.

The fatal flaw of pure reason is, of course, the absence of emotion, and purely explanations of the division between subjective reality and external reality, of which had limited appeal outside the community of intellectuals. The figure most responsible for infusing our understanding of the Cartesian dualism with contextual representation of our understanding with emotional content was the death of God theologian Friedrich Nietzsche 1844-1900. After declaring that God and ‘divine will’, did not exist, Nietzsche reified the ‘existence’ of consciousness in the domain of subjectivity as the ground for individual ‘will’ and summarily reducing all previous philosophical attempts to articulate the ‘will to truth’. The dilemma, forth in, had seemed to mean, by the validation, . . . as accredited for doing of science, in that the claim that Nietzsche’s earlier versions to the ‘will to truth’, disguises the fact that all alleged truths were arbitrarily created in the subjective reality of the individual and are expressed or manifesting the individualism of ‘will’.

In Nietzsche’s view, the separation between mind and matter is more absolute and total than previously been imagined. Based on the assumption that there is no really necessary correspondence between linguistic constructions of reality in human subjectivity and external reality, he deuced that we are all locked in ‘a prison house of language’. The prison as he concluded it, was also a ‘space’ where the philosopher can examine the ‘innermost desires of his nature’ and articulate a new message of individual existence founded on ‘will’.

Those who fail to enact their existence in this space, Nietzsche says, are enticed into sacrificing their individuality on the nonexistent altars of religious beliefs and democratic or socialists’ ideals and become, therefore, members of the anonymous and docile crowd. Nietzsche also invalidated the knowledge claims of science in the examination of human subjectivity. Science, he said. Is not exclusive to natural phenomenons and favors reductionistic examination of phenomena at the expense of mind? It also seeks to reduce the separateness and uniqueness of mind with mechanistic descriptions that disallow and basis for the free exercise of individual will.

The mechanistic paradigms of the late in the nineteenth century where the one Einstein came to know when he studied physics. Most physicists believed that it represented an eternal truth, but Einstein was open to fresh ideas. Inspired by Mach’s critical mind, he demolished the Newtonian ideas of space and time and replaced them with new, ‘relativistic’ notions.

Jean-Paul Sartre (1905-1980), was a French philosopher, dramatist, novelist, and political journalist, who was a leading exponent of existentialism. Jean-Paul Sartre helped to develop existential philosophy through his writings, novels, and plays. Much of Sartre’s work focuses on the dilemma of choice faced by free individuals and on the challenge of creating meaning by acting responsibly in an indifferent world. In stating that ‘man is condemned to be free,’ Sartre reminds us of the responsibility that accompanies human decisions.

Sartre was born in Paris, June 21, 1905, and educated at the Écôle Normale Supérieure in Paris, the University of Fribourg in Switzerland, and the French Institute in Berlin. He taught philosophy at various lycées from 1929 until the outbreak of World War II, when he was called into military service. In 1940-41 he was imprisoned by the Germans; after his release, he taught in Neuilly, France, and later in Paris, and was active in the French Resistance. The German authorities, unaware of his underground activities, permitted the production of his antiauthoritarian play The Flies (1943: translations, 1946) and the publication of his major philosophic work Being and Nothingness (1943: translations, 1953). Sartre gave up teaching in 1945 and founded the political and literary magazine Les Temps Modernes, of which he became the editor in chief. Sartre was active after 1947 as an independent Socialist, critical of both the USSR and the United States in the so-called cold war years. Later, he supported Soviet positions but still frequently criticized Soviet policies. Most of his writing of the 1950s deals with literary and political problems. Sartre rejected the 1964 Nobel Prize in literature, explaining that to accept such an award would compromise his integrity as a writer.

Sartre's philosophic works combine the phenomenology of the German philosopher Edmund Husserl, the metaphysics of the German philosophers Georg Wilhelm Friedrich Hegel and Martin Heidegger, and the social theory of Karl Marx into a single view called existentialism. This view, which relates philosophical theory to life, literature, psychology, and political action, stimulated so much popular interest that existentialism became a worldwide movement.

In his early philosophic work, Being and Nothingness, Sartre conceived humans as beings who create their own world by rebelling against authority and by accepting personal responsibility for their actions, unaided by society, traditional morality, or religious faith. Distinguishing between human existence and the nonhuman world, he maintained that human existence is characterized by nothingness, that is, by the capacity to negate and rebel. His theory of an existential psychoanalysis asserted the inescapable responsibility of all individuals for their own decisions and made the recognition of one's absolute freedom of choice the necessary condition for authentic human existence. His plays and novels express the belief that freedom and acceptance of personal responsibility are the main values in life and that individuals must rely on their creative powers rather than on social or religious authority.

In his later philosophic work Critique of Dialectical Reason (1960: translations, 1976), Sartre's emphasis shifted from existentialist freedom and subjectivity to Marxist social determinism. Sartre argued that the influence of modern society over the individual is so great as to produce serialization, by which he meant loss of self. Individual power and freedom can only be regained through group revolutionary action. Despite this exhortation to revolutionary political activity, Sartre himself did not join the Communist Party, thus retaining the freedom to criticize the Soviet invasions of Hungary in 1956 and Czechoslovakia in 1968. He died in Paris, April 15, 1980.

The part of the theory of design or semiotics, that concerns the relationship between speakers and their signs. the study of the principles governing appropriate conversational moves is called general pragmatized, applied pragmatics treats of special kinds of linguistic interaction such as interviews and speech asking, nevertheless, the philosophical movement that has had a major impact on American culture from the late 19th century to the present. Pragmatism calls for ideas and theories to be tested in practice, by assessing whether acting upon the idea or theory produces desirable or undesirable results. According to pragmatists, all claims about truth, knowledge, morality, and politics must be tested in this way. Pragmatism has been critical of traditional Western philosophy, especially the notions that there are absolute truths and absolute values. Although pragmatism was popular for a time in France, England, and Italy, most observers believe that it encapsulates an American faith in know-how and practicality and an equally American distrust of abstract theories and ideologies.

Pragmatists regard all theories and institutions as tentative hypotheses and solutions. For this reason they believed that efforts to improve society, through such means as education or politics, must be geared toward problem solving and must be ongoing. Through their emphasis on connecting theory to practice, pragmatist thinkers attempted to transform all areas of philosophy, from metaphysics to ethics and political philosophy.

Pragmatism sought a middle ground between traditional ideas about the nature of reality and radical theories of nihilism and irrationalism, which had become popular in Europe in the late 19th century. Traditional metaphysics assumed that the world has a fixed, intelligible structure and that human beings can know absolute or objective truths about the world and about what constitutes moral behavior. Nihilism and irrationalism, on the other hand, denied those very assumptions and their certitude. Pragmatists today still try to steer a middle course between contemporary offshoots of these two extremes.

The ideas of the pragmatists were considered revolutionary when they first appeared. To some critics, pragmatism’s refusal to affirm any absolutes carried negative implications for society. For example, pragmatists do not believe that a single absolute idea of goodness or justice exists, but rather than these concepts are changeable and depend on the context in which they are being discussed. The absence of these absolutes, critics feared, could result in a decline in moral standards. The pragmatists’ denial of absolutes, moreover, challenged the foundations of religion, government, and schools of thought. As a result, pragmatism influenced developments in psychology, sociology, education, semiotics (the study of signs and symbols), and scientific method, as well as philosophy, cultural criticism, and social reform movements. Various political groups have also drawn on the assumptions of pragmatism, from the progressive movements of the early 20th century to later experiments in social reform.

Pragmatism is best understood in its historical and cultural context. It arose during the late 19th century, a period of rapid scientific advancement typified by the theories of British biologist Charles Darwin, whose theories suggested too many thinkers that humanity and society are in a perpetual state of progress. During this same period a decline in traditional religious beliefs and values accompanied the industrialization and material progress of the time. In consequence it became necessary to rethink fundamental ideas about values, religion, science, community, and individuality.

The three most important pragmatists are American philosophers’ Charles Sanders Peirce, William James, and John Dewey. Peirce was primarily interested in scientific method and mathematics; His objective was to infuse scientific thinking into philosophy and society, and he believed that human comprehension of reality was becoming ever greater and that human communities were becoming increasingly progressive. Peirce developed pragmatism as a theory of meaning - in particular, the meaning of concepts used in science. The meaning of the concept ‘brittle,’ for example, is given by the observed consequences or properties that objects called ‘brittle’ exhibit. For Peirce, the only rational way to increase knowledge was to form mental habits that would test ideas through observation, experimentation, or what he called inquiry. Many philosophers known as logical positivists, a group of philosophers who have been influenced by Peirce, believed that our evolving species was fated to get ever closer to Truth. Logical positivists emphasize the importance of scientific verification, rejecting the assertion of positivism that personal experience is the basis of true knowledge.

James moved pragmatism in directions that Peirce strongly disliked. He generalized Peirce’s doctrines to encompass all concepts, beliefs, and actions; he also applied pragmatist ideas to truth as well as to meaning. James was primarily interested in showing how systems of morality, religion, and faith could be defended in a scientific civilization. He argued that sentiment, as well as logic, is crucial to rationality and that the great issues of life - morality and religious belief, for example - are leaps of faith. As such, they depend upon what he called ‘the will to believe’ and not merely on scientific evidence, which can never tell us what to do or what is worthwhile. Critics charged James with relativism (the belief that values depend on specific situations) and with crass expediency for proposing that if an idea or action works the way one intends, it must be right. But James can more accurately be described as a pluralist - someone who believes the world to be far too complex for any one philosophy to explain everything.

Dewey’s philosophy can be described as a version of philosophical naturalism, which regards human experience, intelligence, and communities as ever-evolving mechanisms. Using their experience and intelligence, Dewey believed, human beings can solve problems, including social problems, through inquiry. For Dewey, naturalism led to the idea of a democratic society that allows all members to acquire social intelligence and progress both as individuals and as communities. Dewey held that traditional ideas about knowledge, truth, and values, in which absolutes are assumed, are incompatible with a broadly Darwinian world-view in which individuals and society is progressing. In consequence, he felt that these traditional ideas must be discarded or revised. Indeed, for pragmatists, everything people know and do depend on a historical context and are thus tentative rather than absolute.

Many followers and critics of Dewey believe he advocated elitism and social engineering in his philosophical stance. Others think of him as a kind of romantic humanist. Both tendencies are evident in Dewey’s writings, although he aspired to synthesize the two realms.

The pragmatist’s tradition was revitalized in the 1980s by American philosopher Richard Rorty, who has faced similar charges of elitism for his belief in the relativism of values and his emphasis on the role of the individual in attaining knowledge. Interest has renewed in the classic pragmatists - Pierce, James, and Dewey - as an alternative to Rorty’s interpretation of the tradition.

In an ever-changing world, pragmatism has many benefits. It defends social experimentation as a means of improving society, accepts pluralism, and rejects’ dead dogmas. But a philosophy that offers no final answers or absolutes and that appears vague as a result of trying to harmonize opposites may also be unsatisfactory to some.

One of the five branches into which semiotics is usually divided the study of meaning of words, and their relation of designed to the object studied, a semantic is provided for a formal language when an interpretation or model is specified. Nonetheless, the Semantics, the Greek semantikos, ‘significant,’ the study of the meaning of linguistic signs - that is, words, expressions, and sentences. Scholars of semantics try to one answer such questions as ‘What is the meaning of (the word) ‘X’? They do this by studying what signs are, as well as how signs possess significance - that is, how they are intended by speakers, how they designate (make reference to things and ideas), and how they are interpreted by hearers. The goal of semantics is to match the meanings of signs - what they stand for - with the process of assigning those meanings.

Semantics is studied from philosophical (pure) and linguistic (descriptive and theoretical) approaches, and an approach known as general semantics. Philosophers look at the behavior that goes with the process of meaning. Linguists study the elements or features of meaning as they are related in a linguistic system. General semanticists concentrate on meaning as influencing what people think and do.

These semantic approaches also have broader application. Anthropologists, through descriptive semantics, study what people categorize as culturally important. Psychologists draw on theoretical semantic studies that attempt to describe the mental process of understanding and to identify how people acquire meaning (as well as sound and structure) in language. Animal behaviorists research how and what other species communicate. Exponents of general semantics examine the different values (or connotations) of signs that supposedly mean the same thing (such as ‘the victor at Jena’ and ‘the loser at Waterloo,’ both referring to Napoleon). Also in a general-semantics vein, literary critics have been influenced by studies differentiating literary language from ordinary language and describing how literary metaphors evoke feelings and attitudes.

In the late 19th century Michel Jules Alfred Breal, a French philologist, proposed a ‘science of significations’ that would investigate how sense is attached to expressions and other signs. In 1910 the British philosopher’s Alfred North Whitehead and Bertrand Russell published Principia Mathematica, which strongly influenced the Vienna Circle, a group of philosophers who developed the rigorous philosophical approach known as logical positivism.

One of the leading figures of the Vienna Circle, the German philosopher Rudolf Carnap, made a major contribution to philosophical semantics by developing symbolic logic, a system for analyzing signs and what they designate. In logical positivism, meaning is a relationship between words and things, and its study is empirically based: Because language, ideally, is a direct reflection of reality, signs match things and facts. In symbolic logic, however, mathematical notation is used to state what signs designate and to do so more clearly and precisely than is possible in ordinary language. Symbolic logic is thus itself a language, specifically, a metalanguage (formal technical language) used to talk about an object language (the language that is the object of a given semantic study).

An object language has a speaker (for example, a French woman) using expressions (such as la plume rouge) to designate a meaning (in this case, to indicate a definite pen - a plume - of the color red - rouge). The full description of an object language in symbols is called the semiotic of that language. A language's semiotic has the following aspects: (1) a semantic aspect, in which signs (words, expressions, sentences) are given specific designations; (2) a pragmatic aspect, in which the contextual relations between speakers and signs are indicated; and (3) a syntactic aspect, in which formal relations among the elements within signs (for example, among the sounds in a sentence) are indicated.

An interpreted language in symbolic logic is an object language together with rules of meaning that link signs and designations. Each interpreted sign has a truth condition - a condition that must be met in order for the sign to be true. A sign's meaning is what the sign designates when its truth condition is satisfied. For example, the expression or sign ‘the moon is a sphere’ is understood by someone who knows English; however, although it is understood, it may or may not be true. The expression is true if the thing it is extended to - the moon - is in fact spherical. To determine the sign's truth quality value, one must look at the moon to realize and grasp to its visually perceptive representation of our inseparability with it and the total consciousness of our universe.

The symbolic logic of logical positivist philosophy thus represents an attempt to get at meaning by way of the empirical verifiability of signs - by whether the truth of the sign can be confirmed by observing something in the real world. This attempt at understanding meaning has been only moderately successful. The Austrian-British philosopher Ludwig Wittgenstein rejected it in favor of his ‘ordinary language’ philosophy, in which he asserted that thought is based on everyday language. Not all signs designate things in the world, he pointed out, nor can all signs be associated with truth values. In his approach to philosophical semantics, the rules of meaning are disclosed in how speech is used.

From ordinary-language philosophy has evolved the current theory of speech-act semantics. The British philosopher J. L. Austin claimed that, by speaking, a person performs an act, or does something (such as state, predict, or warn), and that meaning is found in what an expression does, in the act it performs. The American philosopher John R. Searle extended Austin's ideas, emphasizing the need to relate the functions of signs or expressions to their social context. Searle asserted that speech encompasses at least three kinds of acts: (1) elocutionary acts, in which things are said with a certain sense or reference (as in ‘the moon is a sphere’); (2) illocutionary acts, in which such acts as promising or commanding are performed by means of speaking; and (3) perlocutionary acts, in which the speaker, by speaking, does something to someone else (for example, angers, consoles, or persuades someone). The speaker's intentions are conveyed by the illocutionary force that is given to the signs - that is, by the actions implicit in what is said. To be successfully meant, however, the signs must also be appropriate, sincere, consistent with the speaker's general beliefs and conduct, and recognizable as meaningful by the hearer.

What has developed in philosophical semantics, then, is a distinction between truth-based semantics and speech-act semantics. Some critics of speech-act theory believe that it deals primarily with meaning in communication (as opposed to meaning in language) and thus is part of the pragmatic aspect of a language's semiotic - that it relates to signs and to the knowledge of the world shared by speakers and hearers, rather than relating to signs and their designations (semantic aspect) or to formal relations among signs (syntactic aspect). These scholars hold that semantics should be restricted to assigning interpretations to signs alone - independent of a speaker and hearer.

Researchers in descriptive semantics examine what signs mean in particular languages. They aim, for instance, to identify what constitutes nouns or noun phrases and verbs or verb phrases. For some languages, such as English, this is done with subject-predicate analysis. For languages without clear-cut distinctions between nouns, verbs, and prepositions, it is possible to say what the signs mean by analyzing the structure of what are called propositions. In such an analysis, a sign is seen as an operator that combines with one or more arguments (also signs), often nominal argument (noun phrases) or, relates nominal arguments to other elements in the expression (such as prepositional phrases or adverbial phrases). For example, in the expression ‘Bill gives Mary the book, ‘‘gives’ is an operator that relates the arguments ‘Bill, ‘‘Mary,’ and ‘the book.’

Whether using subject-predicate analysis or propositional analysis, descriptive semanticists establish expression classes (classes of items that can substitute for one another within a sign) and classes of items within the conventional parts of speech (such as nouns and verbs). The resulting classes are thus defined in terms of syntax, and they also have semantic roles; that is, the items in these classes perform specific grammatical functions, and in so doing they establish meaning by predicating, referring, making distinctions among entities, relations, or actions. For example, ‘kiss’ belongs to an expression class with other items such as ‘hit’ and ‘see,’ as well as to the conventional part of speech ‘verb,’ in which it is part of a subclass of operators requiring two arguments (an actor and a receiver). In ‘Mary kissed John,’ the syntactic role of ‘kiss’ is to relate two nominal arguments (‘Mary’ and ‘John’), whereas its semantic role is to identify a type of action. Unfortunately for descriptive semantics, however, it is not always possible to find a one-to-one correlation of syntactic classes with semantic roles. For instance, ‘John’ has the same semantic role - to identify a person - in the following two sentences: ‘John is easy to please’ and ‘John is eager to please.’ The syntactic role of ‘John’ in the two sentences, however, is different: In the first, ‘John’ is the receiver of an action; in the second, ‘John’ is the actor.

Linguistic semantics is also used by anthropologists called ethnoscientists to conduct formal semantic analysis (componential analysis) to determine how expressed signs - usually single words as vocabulary items called lexemes - in a language are related to the perceptions and thoughts of the people who speak the language. Componential analysis tests the idea that linguistic categories influence or determine how people view the world; this idea is called the Whorf hypothesis after the American anthropological linguist Benjamin Lee Whorf, who proposed it. In componential analysis, lexemes that have a common range of meaning constitute a semantic domain. Such a domain is characterized by the distinctive semantic features (components) that differentiate individual lexemes in the domain from one another, and also by features shared by all the lexemes in the domain. Such componential analysis points out, for example, that in the domain ‘seat’ in English, the lexemes ‘chair, ‘‘sofa, ‘‘loveseat,’ and ‘bench’ can be distinguished from one another according too many people are accommodated and whether a back support is included. At the same time all these lexemes share the common component, or feature, of meaning ‘something on which to sit.’

Linguists pursuing such componential analysis hope to identify a universal set of such semantic features, from which are drawn the different sets of features that characterize different languages. This idea of universal semantic features has been applied to the analysis of systems of myth and kinship in various cultures by the French anthropologist Claude Lévi-Strauss. He showed that people organize their societies and interpret their place in these societies in ways that, despite apparent differences, have remarkable underlying similarities.

Linguists concerned with theoretical semantics are looking for a general theory of meaning in language. To such linguists, known as transformational-generative grammarians, meaning is part of the linguistic knowledge or competence that all humans possess. A generative grammar as a model of linguistic competence has a phonological (sound-system), a syntactic, and a semantic component. The semantic component, as part of a generative theory of meaning, is envisioned as a system of rules that govern how interpretable signs are interpreted and determine that other signs (such as ‘Colorless green ideas sleep furiously’), although grammatical expressions, are meaningless - semantically blocked. The rules must also account for how a sentence such as ‘They passed the port at midnight’ can have at least two interpretations.

Generative semantics grew out of proposals to explain a speaker's ability to produce and understand new expressions where grammar or syntax fails. Its goal is to explain why and how, for example, a person understands at first hearing that the sentence ‘Colorless green ideas sleep furiously’ has no meaning, even though it follows the rules of English grammar; or how, in hearing a sentence with two possible interpretations (such as ‘They passed the port at midnight’), one decides which meaning applies.

In generative semantics, the idea developed that all information needed to semantically interpret a sign (usually a sentence) is contained in the sentence's underlying grammatical or syntactic deep structure. The deep structure of a sentence involves lexemes (understood as words or vocabulary items composed of bundles of semantic features selected from the proposed universal set of semantic features). On the sentence's surface (that is, when it is spoken) these lexemes will appear as nouns, verbs, adjectives, and other parts of speech - that is, as vocabulary items. When the sentence is formulated by the speaker, semantic roles (such as subject, objects, predicate) are assigned to the lexemes; The listener hears the spoken sentence and interprets the semantic features that are meant.

Whether deep structure and semantic interpretation are distinct from one, another is a matter of controversy. Most generative linguists agree, however, that a grammar should generate the set of semantically well-formed expressions that are possible in a given language, and that the grammar should associate a semantic interpretation with each expression.

Another subject of debate is whether semantic interpretation should be understood as syntactically based (that is, coming from a sentence's deep structure); or whether it should be seen as semantically based. According to Noam Chomsky, an American scholar who is particularly influential in this field, it is possible - in a syntactically based theory - for surface structure and deep structure jointly to determine the semantic interpretation of an expression.

The focus of general semantics is how people evaluate words and how that evaluation influences their behavior. Begun by the Polish American linguist Alfred Korzybski and long associated with the American semanticist and politician S. I. Hayakawa, general semantics has been used in efforts to make people aware of dangers inherent in treating words as more than symbols. It has been extremely popular with writers who use language to influence people's ideas. In their work, these writers use general-semantics guidelines for avoiding loose generalizations, rigid attitudes, inappropriate finality, and imprecision. Some philosophers and linguists, however, have criticized general semantics as lacking scientific rigor, and the approach has declined in popularity.

Positivism, system of philosophy based on experience and empirical knowledge of natural phenomena, in which metaphysics and theology are regarded as inadequate and imperfect systems of knowledge. The doctrine was first called positivism by the 19th-century French mathematician and philosopher Auguste Comte (1798-1857), but some of the positivist concepts may be traced to the British philosopher David Hume, the French philosopher Duc de Saint-Simon, and the German philosopher Immanuel Kant.

Comte chose the word positivism on the ground that it indicated the ‘reality’ and ‘constructive tendency’ that he claimed for the theoretical aspect of the doctrine. He was, in the main, interested in a reorganization of social life for the good of humanity through scientific knowledge, and thus mastering of natural forces. The two primary components of positivism, the philosophy and the polity (or programs of individual and social conduct), were later welded by Comte into a whole under the conception of a religion, in which humanity was the object of worship. A number of Comte's disciples refused, however, to accept this religious development of his philosophy, because it seemed to contradict the original positivist philosophy. Many of Comte's doctrines were later adapted and developed by the British social philosophers John Stuart Mill and Herbert Spencer and by the Austrian philosopher and physicist Ernst Mach.

The principle named But rejected by the English economist and philosopher John Maynard Keyes (1883-1946) whereby if there is no known reason for asserting one than another out of several alternatives, then relative to our knowledge they have an equal probability. Without restriction the principle leads to contradiction, for example, if we know nothing about the nationality of a person, we might argue that the probability is equal that she comes from England or France, and equal that she comes from Scotland or France. But from the first two assertions the probability that she belongs to Britain must be at least double the probability that belongs to France.

A paradox arises when a set class of apparent incontrovertible premises gives unacceptable or contradictory conclusions. To solve a paradox will involve showing either that there is a hidden flaw in the premises, or that the reasoning is erroneous, or that the apparently unacceptable conclusion can, in fact, be tolerated. Paradoxes are therefore important in philosophy, for until one is solved it shows that there is something about our reasoning and our concepts that we do not understand.

By comparison, the moral philosopher and epistemologist Bernard Bolzano (1781-1848) argues, though, that there is something else, an infinity that doe not have this whatever you need it to be elasticity. In fact a truly infinite quantity (for example, the length of a straight ligne unbounded in either direction, meaning : The magnitude of the spatial entity containing all the points determined solely by their abstractly conceivable relation to two fixed points) does not by any means need to be variable, and in adduced example it is in fact not variable. Conversely, it is quite possible for a quantity merely capable of being taken greater than we have already taken it, and of becoming larger than any pre-assigned (finite) quantity, nevertheless it is to mean, in that of all times is merely finite, which holds in particular of every numerical quantity 1, 2, 3, 4, 5.

In other words, for Bolzano there could be a true infinity that was not a variable something that was only bigger than anything you might specify. Such a true infinity was the result of joining two points together and extending that ligne in both directions without stopping. And what is more, he could separate off the demands of calculus, using a finite quality without ever bothering with the slippery potential infinity. Here was both a deeper understanding of the nature of infinity and the basis on which are built in his safe infinity free calculus.

This use of the inexhaustible follows on directly from most Bolzanos’ criticism of the way that ∞ we used as à variable something that would be bigger than anything you could specify, but never quite reached the true, absolute infinity. In Paradoxes of the Infinity Bolzano points out that is possible for a quantity merely capable of becoming larger than any one pre-assigned (finite) quantity, nevertheless to remain at all times merely finite.

Bolzano intended this as à criticism of the way infinity was treated, but Professor Jacquette sees it instead of a way of masking use of practical applications like calculus without the need for weaker words about infinity.

By replacing ∞ with ¤ we do away with one of the most common requirements for infinity, but is there anything left that map out to the real world ? Can we confine infinity to that pure mathematical other world, where anything, however unreal, can be constructed, and forget about it elsewhere ? Surprisingly, this seems to have been the view, at least at one point in time, even of the German mathematician and founder of set-theory Georg Cantor (1845-1918), himself, whose comment in 1883, that only the finite numbers are real.

Keeping within the lines of reason, both these Cambridge mathematician and philosopher Frank Plumpton Ramsey (1903-30) and the Italian mathematician G. Peano (1858-1932) have been to distinguish logical paradoxes and that depend upon the notion of reference or truth (semantic notions), such are the postulates justifying mathematical induction. It ensures that a numerical series is closed, in the sense that nothing but zero and its successors can be numbers. In that any series satisfying a set of axioms can be conceived as the sequence of natural numbers. Candidates from set theory include the Zermelo numbers, where the empty set is zero, and the successor of each number is its unit set, and the von Neuman numbers, where each number is the set of all smaller numbers. A similar and equally fundamental complementarity exists in the relation between zero and infinity. Although the fullness of infinity is logically antithetical to the emptiness of zero, infinity can be obtained from zero with a simple mathematical operation. The division of many numbers by zero is infinity, while the multiplication of any number by zero is zero.

With the set theory developed by the German mathematician and logician Georg Cantor. From 1878 to 1807, Cantor created a theory of abstract sets of entities that eventually became a mathematical discipline. A set, as he defined it, is a collection of definite and distinguished objets in thought or perception conceived as à whole.

Cantor attempted to prove that the process of counting and the definition of integers could be placed on a solid mathematical foundation. His method was to repeatedly place the elements in one set into one-to-one correspondence with those in another. In the case of integers, Cantor showed that each integer (1, 2, 3, . . . n) could be paired with an even integers (2, 4, 6, . . . n), and, therefore, that the set of all integers was equal to the set of all even numbers.

Amazingly, Cantor discovered that some infinite sets were large than others and that infinite sets formed a hierarchy of greater infinities. After this failed attempt to save the classical view of logical foundations and internal consistency of mathematical systems, it soon became obvious that a major crack had appeared in the seemingly sold foundations of number and mathematics. Meanwhile, an impressive number of mathematicians began to see that everything from functional analysis to the theory of real numbers depended on the problematic character of number itself.

While, in the theory of probability Ramsey was the first to show how a personalized theory could be developed, based on precise behavioural notions of preference and expectation. In the philosophy of language, Ramsey was one of the first thinkers to accept a redundancy theory of truth, which hr combined with radical views of the function of man y kinds of propositions. Neither generalizations nor causal propositions, nor those treating probability or ethics, describe facts, but each has a different specific function in our intellectual economy.

Ramsey advocates that of a sentence generated by taking all the sentence affirmed in a scientific theory that use some term, e.g., quark. Replacing the term by a variable, and existentially quantifying into the result. Instead of saying quarks have such-and-such properties, Ramsey postdated that the sentence as saying that there is something that has those properties. If the process is repeated, the sentence gives the topic-neutral structure of the theory, but removes any implications that we know what the term so treated denote. It leaves open the possibility of identifying the theoretical item with whatever it is that best fits the description provided. Nonetheless, it was pointed out by the Cambridge mathematician Newman that if the process is carried out for all except the logical bones of the theory, then by the Löwenheim-Skolem theorem, the result will be interpretable in any domain of sufficient cardinality, and the content of the theory may reasonably be felt to have been lost.

It seems, that the most taken of paradoxes in the foundations of set theory as discovered by Russell in 1901. Some classes have themselves as members: The class of all abstract objects, for example, is an abstract object, whereby, others do not : The class of donkeys is not itself a donkey. Now consider the class of all classes that are not members of themselves, is this class a member of itself, that, if it is, then it is not, and if it is not, then it is.

The paradox is structurally similar to easier examples, such as the paradox of the barber. Such one like a village having a barber in it, who shaves all and only the people who do not have in themselves. Who shaves the barber ? If he shaves himself, then he does not, but if he does not shave himself, then he does not. The paradox is actually just a proof that there is no such barber or in other words, that the condition is inconsistent. All the same, it is no to easy to say why there is no such class as the one Russell defines. It seems that there must be some restriction on the kind of definition that are allowed to define classes and the difficulty that of finding a well-motivated principle behind any such restriction.

The French mathematician and philosopher Henri Jules Poincaré (1854-1912) believed that paradoxes like those of Russell and the barber were due to such as the impredicative definitions, and therefore proposed banning them. But, it tuns out that classical mathematics required such definitions at too many points for the ban to be easily absolved. Having, in turn, as forwarded by Poincaré and Russell, was that in order to solve the logical and semantic paradoxes it would have to ban any collection (set) containing members that can only be defined by means of the collection taken as à whole. It is, effectively by all occurring principles into which have an adopting vicious regress, as to mark the definition for which involves no such failure. There is frequently room for dispute about whether regresses are benign or vicious, since the issue will hinge on whether it is necessary to reapply the procedure. The cosmological argument is an attempt to find a stopping point for what is otherwise seen as being an infinite regress, and, to ban of the predicative definitions.

The investigation of questions that arise from reflection upon sciences and scientific inquiry, are such as called of a philosophy of science. Such questions include, what distinctions in the methods of science ? There is a clear demarcation between scenes and other disciplines, and how do we place such enquires as history, economics or sociology ? And scientific theories probable or more in the nature of provisional conjecture ? Can the be verified or falsified ? What distinguished good from bad explanations ? Might there be one unified since, embracing all the special science ? For much of the 20th century there questions were pursued in a highly abstract and logical framework it being supposed that as general logic of scientific discovery that a general logic of scientific discovery a justification might be found. However, many now take interests in a more historical, contextual and sometimes sociological approach, in which the methods and successes of a science at a particular time are regarded less in terms of universal logical principles and procedure, and more in terms of their availability to methods and paradigms as well as the social context.

In addition, to general questions of methodology, there are specific problems within particular sciences, giving subjects as biology, mathematics and physics.

The intuitive certainty that sparks aflame the dialectic awarenesses for its immediate concerns are either of the truth or by some other in an object of apprehensions, such as à concept. Awareness as such, has to its amounting quality value the place where philosophical understanding of the source of our knowledge are, however, in covering the sensible apprehension of things and pure intuition it is that which stricture sensation into the experience of things accent of its direction that orchestrates the celestial overture into measures in space and time.

The notion that determines how something is seen or evaluated of the status of law and morality especially associated with St Thomas Aquinas and the subsequent scholastic tradition. More widely, any attempt to cement the moral and legal order together with the nature of the cosmos or how the nature of human beings, for which sense it is also found in some Protestant writers, and arguably derivative from a Platonic view of ethics, and is implicit in ancient Stoicism. Law stands above and apart from the activities of human lawmaker, it constitutes an objective set of principles that can be seen true by natural light or reason, and (in religion versions of the theory) that express Gods’ will for creation. Non-religious versions of the theory substitute objective conditions for human flourishing as the source of constraints upon permissible actions and social arrangements. Within the natural law tradition, different views have been held about the relationship between the rule of law about God s will, for instance the Dutch philosopher Hugo Grothius (1583-1645), similarly takes upon the view that the content of natural law is independent of any will, including that of God, while the German theorist and historian Samuel von Pufendorf (1632-94) takes the opposite view, thereby facing the problem of one horn of the Euthyphro dilemma, that simply states, that its dilemma arises from whatever the source of authority is supposed to be, for in which do we care about the general good because it is good, or do we just call good things that we care about. Wherefore, by facing the problem that may be to assume of a strong form, in which it is claimed that various facts entail values, or a weaker form, from which it confines itself to holding that reason by itself is capable of discerning moral requirements that are supped of binding to all human bings regardless of their desires

Although the morality of people send the ethical amount from which the same thing, is that there is a usage that restricts morality to systems such as that of the German philosopher and founder of ethical philosophy Immanuel Kant (1724-1804), based on notions such as duty, obligation, and principles of conduct, reserving ethics for more than the Aristotelian approach to practical reasoning based on the notion of a virtue, and generally avoiding the separation of moral considerations from other practical considerations. The scholarly issues are complex, with some writers seeing Kant as more Aristotelian and Aristotle as, ore involved in a separate sphere of responsibility and duty, than the simple contrast suggests. Some theorists see the subject in terms of a number of laws (as in the Ten Commandments). The status of these laws may be test they are the edicts of a divine lawmaker, or that they are truths of reason, knowable deductively. Other approaches to ethics (e.g., eudaimonism, situation ethics, virtue ethics) eschew general principles as much as possible, frequently disguising the great complexity of practical reasoning. For Kantian notion of the moral law is a binding requirement of the categorical imperative, and to understand whether they are equivalent at some deep level. Kants own applications of the notion are not always convincing, as for one cause of confusion in relating Kants ethics to theories such additional expressivism is that it is easy, but mistaken, to suppose that the categorical nature of the imperative means that it cannot be the expression of sentiment, but must derive from something unconditional or necessary such as the voice of reason.

For which ever reason, the mortal being makes of its presence to the future of weighing of that which one must do, or that which can be required of one. The term carries implications of that which is owed (due) to other people, or perhaps in onself. Universal duties would be owed to persons (or sentient beings) as such, whereas special duty in virtue of specific relations, such as being the child of someone, or having made someone a promise. Duty or obligation is the primary concept of deontological approaches to ethics, but is constructed in other systems out of other notions. In the system of Kant, a perfect duty is one that must be performed whatever the circumstances : Imperfect duties may have to give way to the more stringent ones. In another way, perfect duties are those that are correlative with the right to others, imperfect duties are not. Problems with the concept include the ways in which due needs to be specified (a frequent criticism of Kant is that his notion of duty is too abstract). The concept may also suggest of a regimented view of ethical life in which we are all forced conscripts in a kind of moral army, and may encourage an individualistic and antagonistic view of social relations.

The most generally accepted account of externalism and/or internalism, that this distinction is that a theory of justification is internalist if only if it requiem that all of the factors needed for a belief to be epistemologically justified for a given person be cognitively accessible to that person, internal to cognitive perceptivity, and externalist, if it allows that at least some of the justifying factors need not be thus accessible, so that thy can be external to the believers cognitive perceptive, beyond any such given relations. However, epistemologists often use the distinction between internalist and externalist theories of epistemic justification without offering any very explicit explication.

The externalist/internalist distinction has been mainly applied to theories of epistemic justification : It has also been applied in a closely related way to accounts of knowledge and in a rather different way to accounts of belief and thought contents.

The internalist requirement of cognitive accessibility can be interpreted in at least two ways : A strong version of internalism would require that the believe actually be aware of the justifying factor in order to be justified : While a weaker version would require only that he be capable of becoming aware of them by focussing his attentions appropriately, but without the need for any change of position, new information, etc. Though the phrase cognitively accessible suggests the weak interpretation, the main intuitive motivation for internalism, viz the idea that epistemic justification requires that the believe actually have in his cognitive possession a reason for thinking that the belief is true, and would require the strong interpretation.

Perhaps, the clearest example of an internalist position would be a Foundationalist view according to which foundational beliefs pertain to immediately experienced states of mind and other beliefs are justified by standing in cognitively accessible logical or inferential relations to such foundational beliefs. Such a view could count as either a strong or a weak version of internalism, depending on whether actual awareness of the justifying elements or only the capacity to become aware of them is required. Similarly, a coherent view could also be internalist, if both the beliefs or other states with which a justification belief is required to cohere and the coherence relations themselves are reflectively accessible.

It should be carefully noticed that when internalism is construed in this way, it is neither necessary nor sufficient by itself for internalism that the justifying factors literally be internal mental states of the person in question. Not necessary, necessary, because on at least some views, e.g., a direct realist view of perception, something other than a mental state of the believe can be cognitively accessible : Not sufficient, because there are views according to which at least some mental states need not be actual (strong version) or even possible (weak version) objects of cognitive awareness. Also, on this way of drawing the distinction, a hybrid view, according to which some of the factors required for justification must be cognitively accessible while others need not and in general will not be, would count as an externalist view. Obviously too, a view that was externalist in relation to a strong version of internalism (by not requiring that the believe actually be aware of all justifiable factors) could still be internalist in relation to a weak version (by requiring that he at least be capable of becoming aware of them).

The most prominent recent externalist views have been versions of reliabilism, whose requirements for justification is roughly that the belief be produced in a way or via a process that makes of objectively likely that the belief is true. What makes such a view externalist is the absence of any requirement that the person for whom the belief is justified have any sort of cognitive access to the relations of reliability in question. Lacking such access, such a person will in general have no reason for thinking that the belief is true or likely to be true, but will, on such an account, nonetheless be epistemically justified in according it. Thus such a view arguably marks a major break from the modern epistemological tradition, stemming from Descartes, which identifies epistemic justification with having a reason, perhaps even a conclusive reason for thinking that the belief is true. An epistemologist working within this tradition is likely to feel that the externalist, than offering a competing account of the same concept of epistemic justification with which the traditional epistemologist is concerned, has simply changed the subject.

The main objection to externalism rests on the intuitive certainty that the basic requirement for epistemic justification is that the acceptance of the belief in question be rational or responsible in relation to the cognitive goal of truth, which seems to require in turn that the believe actually be dialectally aware of a reason for thinking that the belief is true (or, at the very least, that such a reason be available to him). Since the satisfaction of an externalist condition is neither necessary nor sufficient for the existence of such a cognitively accessible reason, it is argued, externalism is mistaken as an account of epistemic justification. This general point has been elaborated by appeal to two sorts of putative intuitive counter-examples to externalism. The first of these challenges the necessity of belief which seem intuitively to be justified, but for which the externalist conditions are not satisfied. The standard examples in this sort are cases where beliefs are produced in some very nonstandard way, e.g., by a Cartesian demon, but nonetheless, in such a way that the subjective experience of the believe is indistinguishable from that of someone whose beliefs are produced more normally. The intuitive claim is that the believe in such a case is nonetheless epistemically justified, as much so as one whose belief is produced in a more normal way, and hence that externalist account of justification must be mistaken.

Perhaps the most striking reply to this sort of counter-example, on behalf of a cognitive process is to be assessed in normal possible worlds, i.e., in possible worlds that are actually the way our world is common-seismically believed to be, than in the world which contains the belief being judged. Since the cognitive processes employed in the Cartesian demon cases are, for which we may assume, reliable when assessed in this way, the reliability can agree that such beliefs are justified. The obvious, to a considerable degree of bringing out the issue of whether it is or not an adequate rationale for this construal of Reliabilism, so that the reply is not merely a notional presupposition guised as having representation.

The correlative way of elaborating on the general objection to justificatory externalism challenges the sufficiency of the various externalist conditions by citing cases where those conditions are satisfied, but where the believers in question seem intuitively not to be justified. In this context, the most widely discussed examples have to do with possible occult cognitive capacities, like clairvoyance. Considering the point in application once, again, to Reliabilism, the claim is that to think that he has such a cognitive power, and, perhaps, even good reasons to the contrary, is not rational or responsible and therefore not epistemically justified in accepting the belief that result from his clairvoyance, despite the fact that the Reliabilist condition is satisfied.

One sort of response to this latter sorts of objection is to bite the bullet and insist that such believers are in fact justified, dismissing the seeming intuitions to the contrary as latent internalist prejudice. A more widely adopted response attempts to impose additional conditions, usually of a roughly internalized sort, which will rule out the offending example, while stopping far of a full internalism. But, while there is little doubt that such modified versions of externalism can handle particular cases, as well enough to avoid clear intuitive implausibility, the usually problematic cases that they cannot handle, and also whether there is and clear motivation for the additional requirements other than the general internalist view of justification that externalist are committed to reject.

A view in this same general vein, one that might be described as a hybrid of internalism and externalism holds that epistemic justification requires that there is a justificatory factor that is cognitively accessible to the believe in question (though it need not be actually grasped), thus ruling out, e.g., a pure Reliabilism. At the same time, however, though it must be objectively true that beliefs for which such a factor is available are likely to be true, in addition, the fact need not be in any way grasped or cognitively accessible to the believe. In effect, of the premises needed to argue that a particular belief is likely to be true, one must be accessible in a way that would satisfy at least weakly internalized. The internalist will respond that this hybrid view is of no help at all in meeting the objection and has no belief nor is it held in the rational, responsible way that justification intuitively seems to require, for the believe in question, lacking one crucial premise, still has no reason at all for thinking that his belief is likely to be true.

An alternative to giving an externalist account of epistemic justification, one which may be more defensible while still accommodating many of the same motivating concerns, is to give an externalist account of knowledge directly, without relying on an intermediate account of justification. Such a view will obviously have to reject the justified true belief account of knowledge, holding instead that knowledge is true belief which satisfies the chosen externalist condition, e.g., a result of a reliable process (and perhaps, further conditions as well). This makes it possible for such a view to retain internalist account of epistemic justification, though the centrality of that concept to epistemology would obviously be seriously diminished.

Such an externalist account of knowledge can accommodate the commonsense conviction that animals, young children, and unsophisticated adults posses knowledge, though not the weaker conviction (if such a conviction does exists) that such individuals are epistemically justified in their beliefs. It is also at least less vulnerable to internalist counter-examples of the sort discussed, since the intuitions involved there pertain more clearly to justification than to knowledge. What is uncertain is what ultimate philosophical significance the resulting conception of knowledge is supposed to have. In particular, does it have any serious bearing on traditional epistemological problems and on the deepest and most troubling versions of scepticism, which seems in fact to be primarily concerned with justification, the an knowledge ?`

A rather different use of the terms internalism and externalism has to do with the issue of how the content of beliefs and thoughts is determined : According to an internalist view of content, the content of such intention states depends only on the non-relational, internal properties of the individuals mind or grain, and not at all on his physical and social environment : While according to an externalist view, content is significantly affected by such external factors and suggests a view that appears of both internal and external elements are standardly classified as an external view.

As with justification and knowledge, the traditional view of content has been strongly internalized in character. The main argument for externalism derives from the philosophy of language, more specifically from the various phenomena pertaining to natural kind terms, indexicals, etc. that motivate the views that have come to be known as direct reference theories. Such phenomena seem at least to show that the belief or thought content that can be properly attributed to a person is dependant on facts about his environment, e.g., whether he is on Earth or Twin Earth, what is fact pointing at, the classificatory criteria employed by expects in his social group, etc. - not just on what is going on internally in his mind or brain.

An objection to externalist account of content is that they seem unable to do justice to our ability to know the content of our beliefs or thought from the inside, simply by reflection. If content is depend on external factors pertaining to the environment, then knowledge of content should depend on knowledge of these factors - which will not in general be available to the person whose belief or thought is in question.

The adoption of an externalized account of mental content would seem to support an externalist account of justification, by way that if part or all of the content of a belief inaccessible to the believe, then both the justifying status of other beliefs in relation to that content and the status of that content justifying the beliefs will be similarly inaccessible, thus contravening the internalist requirement for justification. An internalist must insist that there are no justifiable relations of these sorts, that our internally associable content can either be justified or justly anything else : But such a response appears lame unless it is coupled with an attempt to show that the externalist account of content is mistaken.

A great deal of philosophical effort has been lavished on the attempt to naturalize content, i.e. to explain in non-semantic, Non-intentional terms what it is for something to be represental (have content) and what it is for something to have some particular content rather than some other. There appear to be only four types of theory that have been proposed: Theories that ground representation in (1) similarity, (2) conversance, (3) functional role, (4) teleology.

Similarly, theories hold that 'r' represents 'x' in virtue of being similar to 'x'. This has seemed hopeless to most as a theory of mental representation because it appears to require that things in the brain must share properties with the things they represent: To represent a cat as furry appears to require something furry in the brain. Perhaps, a notion of similarity that is naturalistic and does not involve property sharing can be worked out, but it is not obvious how.

Covariance theories hold that 'r's' represent 'x' is grounded in the fact that ‘r's’, occasion canaries with that of 'x'. This is most compelling he n one thinks about detection systems, the firing a neural structures in the visual system is said to represent vertical orientations, if its firing varies with the occurrence of vertical lines in the visual field of perceptivity.

Functional role theories hold that 'r's' represent 'x' is grounded in the functional role 'r' has in the representing system, i.e., on the relations imposed by specific cognitive processes imposed by specific cognitive processes between 'r' and other representations in the system's repertoire. Functional role theories take their cue from such common-sense ideas as that people cannot believer that cats are furry if they did not know that cats are animals or that fur is like hair.

Teleological theories hold that 'r' represent 'x' if it is 'r's' function to indicate, i.e., covary with 'x'. Teleological theories differ depending on the theory of functions they import. Perhaps the most important distinction is that between historical theories of functions. Historical theories individuated functional states (hence contents) in a way that is sensitive to the historical development of the state, i.e., to factors such as the way the state was 'learned', or the way it evolved. An historical theory might hold that the function of 'r' is to indicate 'x' only if the capacity to token 'r' was developed (selected, learned) because it indicates 'x'. Thus, a state physically indistinguishable from 'r's' historical origins would not represent 'x' according to historical theories.

Theories of representational content may be classified according to whether they are atomistic or holistic and according to whether they are externalistic or internalistic, whereby, emphasizing the priority of a whole over its parts. Furthermore, in the philosophy of language, this becomes the claim that the meaning of an individual word or sentence can only be understood in terms of its relation to an indefinitely larger body of language, such as a whole theory, or even a whole language or form of life. In the philosophy of mind a mental state similarly may be identified only in terms of its relations with others. Moderate holism may allow the other things besides these relationships also count; extreme holism would hold that a network of relationships is all that we have. A holistic view of science holds that experience only confirms or disconfirms large bodies of doctrine, impinging at the edges, and leaving some leeway over the adjustment that it requires.

Once, again, in the philosophy of mind and language, the view that what is thought, or said, or experienced, is essentially dependent on aspects of the world external to the mind of the subject. The view goes beyond holding that such mental states are typically caused by external factors, to insist that they could not have existed as they now do without the subject being embedded in an external world of a certain kind. It is these external relations that make up the essence or identify of the mental state. Externalism is thus opposed to the Cartesian separation of the mental from the physical, since that holds that the mental could in principle exist as it does even if there were no external world at all. Various external factors have been advanced as ones on which mental content depends, including the usage of experts, the linguistic, norms of the community. And the general causal relationships of the subject. In the theory of knowledge, externalism is the view that a person might know something by being suitably situated with respect to it, without that relationship being in any sense within his purview. The person might, for example, be very reliable in some respect without believing that he is. The view allows that you can know without being justified in believing that you know.

However, atomistic theories take a representation's content to be something that can be specified independent entity of that representation' s relations to other representations. What the American philosopher of mind, Jerry Alan Fodor (1935-) calls the crude causal theory, for example, takes a representation to be a
cow
- a menial representation with the same content as the word 'cow' - if its tokens are caused by instantiations of the property of being-a-cow, and this is a condition that places no explicit constraints on how
cow
's must or might relate to other representations. Holistic theories contrasted with atomistic theories in taking the relations a representation bears to others to be essential to its content. According to functional role theories, a representation is a
cow
if it behaves like a
cow
should behave in inference.

Internalist theories take the content of a representation to be a matter determined by factors internal to the system that uses it. Thus, what Block (1986) calls 'short-armed' functional role theories are internalist. Externalist theories take the content of a representation to be determined, in part at least, by factors external to the system that uses it. Covariance theories, as well as telelogical theories that invoke an historical theory of functions, take content to be determined by 'external' factors. Crossing the atomist-holistic distinction with the internalist-externalist distinction.

Externalist theories (sometimes called non-individualistic theories) have the consequence that molecule for molecule are coincide with the identical cognitive systems might yet harbour representations with different contents. This has given rise to a controversy concerning 'narrow' content. If we assume some form of externalist theory is correct, then content is, in the first instance 'wide' content, i.e., determined in part by factors external to the representing system. On the other hand, it seems clear that, on plausible assumptions about how to individuate psychological capacities, internally equivalent systems must have the same psychological capacities. Hence, it would appear that wide content cannot be relevant to characterizing psychological equivalence. Since cognitive science generally assumes that content is relevant to characterizing psychological equivalence, philosophers attracted to externalist theories of content have sometimes attempted to introduce 'narrow' content, i.e., an aspect or kind of content that is equivalent internally equivalent systems. The simplest such theory is Fodor's idea (1987) that narrow content is a function from contents (i.e., from whatever the external factors are) to wide contents.

All the same, what a person expresses by a sentence is often a function of the environment in which he or she is placed. For example, the disease I refer to by the term like 'arthritis', or the kind of tree I refer to as a 'Maple' will be defined by criteria of which I know next to nothing. This raises the possibility of imagining two persons in rather different environments, but in which everything appears the same to each of them. The wide content of their thoughts and sayings will be different if the situation surrounding them is appropriately different: 'situation' may include the actual objects they perceive or the chemical or physical kinds of object in the world they inhabit, or the history of their words, or the decisions of authorities on what counts as an example, of one of the terms they use. The narrow content is that part of their thought which remains identical, through their identity of the way things appear, regardless of these differences of surroundings. Partisans of wide content may doubt whether any content in this sense narrow, partisans of narrow content believer that it is the fundamental notion, with wide content being explicable in terms of narrow content plus context.

Even so, the distinction between facts and values has outgrown its name: it applies not only to matters of fact vs, matters of value, but also to statements that something is, vs. statements that something ought to be. Roughly, factual statements - 'is statements' in the relevant sense - represent some state of affairs as obtaining, whereas normative statements - evaluative, and deontic ones - attribute goodness to something, or ascribe, to an agent, an obligation to act. Neither distinction is merely linguistic. Specifying a book's monetary value is making a factual statement, though it attributes a kind of value. 'That is a good book' expresses a value judgement though the term 'value' is absent (nor would 'valuable' be synonymous with 'good'). Similarly, 'we are morally obligated to fight' superficially expresses a statement, and 'By all indications it ough to rain' makes a kind of ought-claim; but the former is an ought-statement, the latter an (epistemic) is-statement.

Theoretical difficulties also beset the distinction. Some have absorbed values into facts holding that all value is instrumental, roughly, to have value is to contribute - in a factual analyzable way - to something further which is (say) deemed desirable. Others have suffused facts with values, arguing that facts (and observations) are 'theory-impregnated' and contending that values are inescapable to theoretical choice. But while some philosophers doubt that fact/value distinctions can be sustained, there persists a sense of a deep difference between evaluating, or attributing an obligation and, on the other hand, saying how the world is.

Fact/value distinctions, may be defended by appeal to the notion of intrinsic value, value a thing has in itself and thus independently of its consequences. Roughly, a value statement (proper) is an ascription of intrinsic value, one to the effect that a thing is to some degree good in itself. This leaves open whether ought-statements are implicitly value statements, but even if they imply that something has intrinsic value - e.g., moral value - they can be independently characterized, say by appeal to rules that provide (justifying) reasons for action. One might also ground the fact value distinction in the attributional (or even motivational) component apparently implied by the making of valuational or deontic judgements: Thus, 'it is a good book, but that is no reason for a positive attribute towards it' and 'you ought to do it, but there is no reason to' seem inadmissible, whereas, substituting, 'an expensive book' and 'you will do it' yields permissible judgements. One might also argue that factual judgements are the kind which are in principle appraisable scientifically, and thereby anchor the distinction on the factual side. This ligne is plausible, but there is controversy over whether scientific procedures are 'value-free' in the required way.

Philosophers differ regarding the sense, if any, in which epistemology is normative (roughly, valuational). But what precisely is at stake in this controversy is no clearly than the problematic fact/value distinction itself. Must epistemologists as such make judgements of value or epistemic responsibility? If epistemology is naturalizable, then even epistemic principles simply articulate under what conditions - say, appropriate perceptual stimulations - a belief is justified, or constitutes knowledge. Its standards of justification, then would be like standards of, e.g., resilience for bridges. It is not obvious, however, that there appropriate standards can be established without independent judgements that, say, a certain kind of evidence is good enough for justified belief (or knowledge). The most plausible view may be that justification is like intrinsic goodness, though it supervenes on natural properties, it cannot be analysed wholly in factual statements.

Thus far, belief has been depicted as being all-or-nothing, however, as a resulting causality for which we have grounds for thinking it true, and, all the same, its acceptance is governed by epistemic norms, and, least of mention, it is partially subject to voluntary control and has functional affinities to belief. Still, the notion of acceptance, like that of degrees of belief, merely extends the standard picture, and does not replace it.

Traditionally, belief has been of epistemological interest in its propositional guise: 'S' believes that 'p', where 'p' is a reposition towards which an agent, 'S' exhibits an attitude of acceptance. Not all belief is of this sort. If I trust you to say, I believer you. And someone may believer in Mr. Radek, or in a free-market economy, or in God. It is sometimes supposed that all belief is 'reducible' to propositional belief, belief-that. Thus, my believing you might be thought a matter of my believing, is, perhaps, that what you say is true, and your belief in free markets or God, is a matter of your believing that free-market economies are desirable or that God exists.

Some philosophers have followed St, Thomas Aquinas (1225-74), in supposing that to believer in God is simply to believer that certain truths hold while others argue that belief-in is a distinctive attitude, on that includes essentially an element of trust. More commonly, belief-in has been taken to involve a combination of propositional belief together with some further attitude.

The moral philosopher Richard Price (1723-91) defends the claim that there are different sorts of belief-in, some, but not all reducible to beliefs-that. If you believer in God, you believer that God exists, that God is good, you believer that God is good, etc. But according to Price, your belief involves, in addition, a certain complex pro-attitude toward its object. Even so, belief-in outruns the evidence for the corresponding belief-that. Does this diminish its rationality? If belief-in presupposes believes-that, it might be thought that the evidential standards for the former must be, at least, as high as standards for the latter. And any additional pro-attitude might be thought to require a further layer of justification not required for cases of belief-that.

Belief-in may be, in general, less susceptible to alternations in the face of unfavourable evidence than belief-that. A believe who encounters evidence against God's existence may remain unshaken in his belief, in part because the evidence does not bear on his pro-attitude. So long as this is united with his belief that God exists, the reasonably so in a way that an ordinary propositional belief that would not.

Some philosophers think that the category of knowing for which true. Justified believing (accepting) is a requirement constituting only a species of Propositional knowledge, construed as an even broader category. They have proposed various examples of 'PK' that do not satisfy the belief and/or justification conditions of the tripartite analysis. Such cases are often recognized by analyses of Propositional knowledge in terms of powers, capacities, or abilities. For instance, Alan R. White (1982) treats 'PK' as merely the ability to provide a correct answer to a possible question, however, White may be equating 'producing' knowledge in the sense of producing 'the correct answer to a possible question' with 'displaying' knowledge in the sense of manifesting knowledge. (White, 1982). The latter can be done even by very young children and some non-human animals independently of their being asked questions, understanding questions, or recognizing answers to questions. Indeed, an example that has been proposed as an instance of knowing that 'h' without believing or accepting that 'h' can be modified so as to illustrate this point. Two examples concern an imaginary person who has no special training or information about horses or racing, but who in an experiment persistently and correctly picks the winners of upcoming horseraces. If the example is modified so that the hypothetical 'seer' never picks winners but only muses over whether those horses wight win, or only reports those horses winning, this behaviour should be as much of a candidate for the person's manifesting knowledge that the horse in question will win as would be the behaviour of picking it as a winner.

These considerations expose limitations in Edward Craig's analysis (1990) of the concept of knowing of a person's being a satisfactory information in relation to an inquirer who wants to find out whether or not 'h'. Craig realizes that counterexamples to his analysis appear to be constituted by Knower who is too recalcitrant to inform the inquirer, or to incapacitate to inform, or too discredited to be worth considering (as with the boy who cried 'Wolf'). Craig admits that this might make preferably some alternative view of knowledge as a different state that helps to explain the presence of the state of being a suitable informant when the latter does obtain. Such an alternate, which offers a recursive definition that concerns one's having the power to proceed in a way representing the state of affairs, causally involved in one's proceeding in this way. When combined with a suitable analysis of representing, this theory of propositional knowledge can be unified with a structurally similar analysis of knowing how to do something.

Knowledge and belief, according to most epistemologists, knowledge entails belief, so that I cannot know that such and such is the case unless I believe that such and such am the case. Others think this entailment thesis can be rendered more accurately if we substitute for belief some closely related attitude. For instance, several philosophers would prefer to say that knowledge entail psychological certainties (Prichard, 1950 and Ayer, 1956) or conviction (Lehrer, 1974) or acceptance (Lehrer, 1989). Nonetheless, there are arguments against all versions of the thesis that knowledge requires having a belief-like attitude toward the known. These arguments are given by philosophers who think that knowledge and belief (or a facsimile) are mutually incompatible (the incomparability thesis), or by ones who say that knowledge does not entail belief, or vice versa, so that each may exist without the other, but the two may also coexist (the separability thesis).

The incompatibility thesis is sometimes traced to Plato 429-347 Bc. , In view of his claim that knowledge is infallible while belief or opinion is fallible ('Republic' 476-9). But this claim would not support the thesis. Belief might be a component of an infallible form of knowledge in spite of the fallibility of belief. Perhaps, knowledge involves some factor that compensates for the fallibility of belief.

A. Duncan-Jones (1939: Also Vendler, 1978) cites linguistic evidence to back up the incompatibility thesis. He notes that people often say 'I do not believe she is guilty. I know she is' and the like, which suggest that belief rule out knowledge. However, as Lehrer (1974) indicates, the above exclamation is only a more emphatic way of saying 'I do not just believe she is guilty, I know she is' where 'just' makes it especially clear that the speaker is signalling that she has something more salient than mere belief, not that she has something inconsistent with belief, namely knowledge. Compare: 'You do not hurt him, you killed him'.

H.A. Prichard (1966) offers a defence of the incompatibility thesis that hinges on the equation of knowledge with certainty (both infallibility and psychological certitude) and the assumption that when we believe in the truth of a claim we are not certain about its truth. Given that belief always involves uncertainty while knowledge never dies, believing something rules out the possibility of knowing it. Unfortunately, however, Prichard gives 'us' no goods reason to grant that states of belief are never ones involving confidence. Conscious beliefs clearly involve some level of confidence, to suggest that we cease to believe things about which we are completely confident is bizarre.

A.D. Woozley (1953) defends a version of the separability thesis. Woozley's version, which deals with psychological certainty rather than belief per se, is that knowledge can exist in the absence of confidence about the item known, although might also be accompanied by confidence as well. Woozley remarks that the test of whether I know something is 'what I can do, where what I can do may include answering questions'. On the basis of this remark he suggests that even when people are unsure of the truth of a claim, they might know that the claim is true. We unhesitatingly attribute knowledge to people who give correct responses on examinations even if those people show no confidence in their answers. Woozley acknowledges, however, that it would be odd for those who lack confidence to claim knowledge. It would be peculiar to say, 'I am unsure my answer is true: Still, I know it is correct'. But this tension Woozley explains using a distinction between conditions under which we are justified in making a claim (such as a claim to know something), and conditions under which the claim we make are true. While 'I know such and such' might be true even if I am unsure whether such and such holds, nonetheless it would be inappropriate for me to claim that I know that such and such unless I were sure of the truth of my claim.

Colin Radford (1966) extends Woozley's defence of the separability thesis. In Radford's view, not only is knowledge compatible with the lack of certainty, it is also compatible with a complete lack of belief. He argues by example. In one example, Jean has forgotten that he learned some English history year's priori and yet he is able to give several correct responses to questions such as 'When did the Battle of Hastings occur'? Since he forgot that he took history, he considers the correct response to be no more than guesses. Thus, when he says that the Battle of Hastings took place in 1066 he would deny having the belief that the Battle of Hastings took place in 1066. A disposition he would deny being responsible (or having the right to be convincing) that 1066 was the correct date. Radford would nonetheless insist that Jean know when the Battle occurred, since clearly be remembering the correct date. Radford admits that it would be inappropriate for Jean to say that he knew when the Battle of Hastings occurred, but, like Woozley he attributes the impropriety to a fact about when it is and is not appropriate to claim knowledge. When we claim knowledge, we ought, at least to believe that we have the knowledge we claim, or else our behaviour is 'intentionally misleading'.

Those that agree with Radford's defence of the separability thesis will probably think of belief as an inner state that can be detected through introspection. That Jean lack's beliefs about English history are plausible on this Cartesian picture since Jean does not find himself with any beliefs about English history when we seek them out. One might criticize Radford, however, by rejecting that Cartesian view of belief. One could argue that some beliefs are thoroughly unconscious, for example. Or one could adopt a behaviourist conception of belief, such as Alexander Bain's (1859), according to which having beliefs is a matter of the way people are disposed to behave (and has not Radford already adopted a behaviourist conception of knowledge?) Since Jean gives the correct response when queried, a form of verbal behaviour, a behaviourist would be tempted to credit him with the belief that the Battle of Hastings occurred in 1066.

D.M. Armstrong (1873) takes a different tack against Radford. Jean does know that the Battle of Hastings took place in 1066. Armstrong will grant Radfod that point, in fact, Armstrong suggests that Jean believe that 1066 is not the date the Battle of Hastings occurred, for Armstrong equates the belief that such and such is just possible but no more than just possible with the belief that such and such is not the case. However, Armstrong insists, Jean also believes that the Battle did occur in 1066. After all, had Jean been mistaught that the Battle occurred in 1066, and subsequently 'guessed' that it took place in 1066, we would surely describe the situation as one in which Jean's false belief about the Battle became unconscious over time but persisted of a memory trace that was causally responsible for his guess. Out of consistency, we must describe Radford's original case as one that Jean's true belief became unconscious but persisted long enough to cause his guess. Thus, while Jean consciously believes that the Battle did not occur in 1066, unconsciously he does believe it occurred in 1066. So after all, Radford does not have a counterexample to the claim that knowledge entails belief.

Armstrong's response to Radford was to reject Radford's claim that the examinee lacked the relevant belief about English history. Another response is to argue that the examinee lacks the knowledge Radford attributes to him (cf. Sorenson, 1982). If Armstrong is correct in suggesting that Jean believes both that 1066 is and that it is not the date of the Battle of Hastings, one might deny Jean knowledge on the grounds that people who believe the denial of what they believe cannot be said t know the truth of their belief. Another strategy might be to compare the examine case with examples of ignorance given in recent attacks on externalist accounts of knowledge (needless to say. Externalists themselves would tend not to favour this strategy). Consider the following case developed by BonJour (1985): For no apparent reason, Samantha believes that she is clairvoyant. Again, for no apparent reason, she one day comes to believe that the President is in New York City, even though she has every reason to believe that the President is in Washington, D.C. In fact, Samantha is a completely reliable clairvoyant, and she has arrived at her belief about the whereabouts of the President thorough the power of her clairvoyance. Yet surely Samantha's belief is completely irrational. She is not justified in thinking what she does. If so, then she does not know where the President is. But Radford's examinee is unconventional. Even if Jean lacks the belief that Radford denies him, Radford does not have an example of knowledge that is unattended with belief. Suppose that Jean's memory had been sufficiently powerful to produce the relevant belief. As Radford says, in having every reason to suppose that his response is mere guesswork, and he has every reason to consider his belief false. His belief would be an irrational one, and hence one about whose truth Jean would be ignorant.

Least has been of mention to an approaching view from which 'perception' basis upon itself as a fundamental philosophical topic both for its central place in ant theory of knowledge, and its central place un any theory of consciousness. Philosophy in this area is constrained by a number of properties that we believe to hold of perception, (1) It gives 'us' knowledge of the world around 'us'. (2) We are conscious of that world by being aware of 'sensible qualities': Colour, sounds, tastes, smells, felt warmth, and the shapes and positions of objects in the environment. (3) Such consciousness is affected through highly complex information channels, such as the output of the three different types of colour-sensitive cells in the eye, or the channels in the ear for interpreting pulses of air pressure as frequencies of sound. (4) There ensues even more complex neurophysiological coding of that information, and eventually higher-order brain functions bring it about that we interpreted the information so received. (Much of this complexity has been revealed by the difficulties of writing programs enabling computers to recognize quite simple aspects of the visual scene.) The problem is to avoid thinking of here being a central, ghostly, conscious self, fed information in the same way that a screen if fed information by a remote television camera. Once such a model is in place, experience will seem like a veil getting between 'us' and the world, and the direct objects of perception will seem to be private items in an inner theatre or sensorium. The difficulty of avoiding this model is epically cute when we considered the secondary qualities of colour, sound, tactile feelings and taste, which can easily seem to have a purely private existence inside the perceiver, like sensation of pain. Calling such supposed items names like 'sense-data' or 'percepts’ exacerbate the tendency, but once the model is in place, the first property, that perception gives 'us' knowledge of the world and its surrounding surfaces, is quickly threatened, for there will now seem little connection between these items in immediate experience and any independent reality. Reactions to this problem include 'scepticism' and 'idealism'.

A more hopeful approach is to claim that the complexities of (3) and (4) explain how we can have direct acquaintance of the world, than suggesting that the acquaintance we do have been at best indirect. It is pointed out that perceptions are not like sensation, precisely because they have a content, or outer-directed nature. To have a perception is to be aware of the world for being such-and-such a way, than to enjoy a mere modification of sensation. But such direct realism has to be sustained in the face of the evident personal (neurophysiological and other) factors determining how we perceive. One approach is to ask why it is useful to be conscious of what we perceive, when other aspects of our functioning work with information determining responses without any conscious awareness or intervention. A solution to this problem would offer the hope of making consciousness part of the natural world, than a strange optional extra.

Furthering, perceptual knowledge is knowledge acquired by or through the senses and includes most of what we know. We cross intersections when we see the light turn green, head for the kitchen when we smell the roast burning, squeeze the fruit to determine its ripeness, and climb out of bed when we hear the alarm ring. In each case we come to know something-that the light has turned green, that the roast is burning, that the melon is overripely, and that it is time to get up-by some sensory means. Seeing that the light has turned green is learning something-that, the light has turned green-by use of the eyes. Feeling that the melon is overripe is coming to know a fact-that the melon is overripe-by one's sense to touch. In each case the resulting knowledge is somehow based on, derived from or grounded in the sort of experience that characterizes the sense modality in question.

Much of our perceptual knowledge is indirect, dependent or derived. By this I mean that the facts we describe ourselves as learning, as coming to know, by perceptual means are pieces of knowledge that depend on our coming to know something else, some other fact, in a more direct way. We see, by the gauge, that we need gas, see, by the newspapers, that our team has lost again, see, by her expression, that she is nervous. This derived or dependent sort of knowledge is particularly prevalent in the cases of vision, but it occurs, to a lesser degree, in every sense modality. We install bells and other noise-makers so that we calm for example, hear (by the bell) that someone is at the door and (by the alarm) that its time to get up. When we obtain knowledge in this way, it is clear that unless one sees-hence, comes to know something about the gauge (that it says) and (hence, know) that one is described as coming to know by perceptual means. If one cannot hear that the bell is ringing, one cannot-in at least in this way-hear that one's visitors have arrived. In such cases one sees (hears, smells, etc.) that 'a' is 'F', coming to know thereby that 'a' is 'F', by seeing (hearing, etc.) that some other condition, 'b's' being 'G', obtains when this occurs, the knowledge (that 'a' is 'F') is derived from, or dependent on, the more basic perceptual knowledge that 'b' is 'G'.

Perhaps as a better strategy is to tie an account save that part that evidence could justify explanation for it is its truth alone. Since, at least the times of Aristotle philosophers of explanatory knowledge have emphasized of its importance that, in its simplest therms, we want to know not only what is the composite peculiarities and particular points of issue but also why it is. This consideration suggests that we define an explanation as an answer to a why-question. Such a definition would, however, be too broad, because some why-questions are requests for consolation (Why did my son have to die?) Or moral justification (Why should women not be paid the same as men for the same work?) It would also be too narrow because some explanations are responses to how-questions (How does radar work?) Or how-possibility-questions (How is it possible for cats always to land their feet?)

In its overall sense, 'to explain' means to make clear, to make plain, or to provide understanding. Definitions of this sort are philosophically unhelpful, for the terms used in the deficient are no less problematic than the term to be defined. Moreover, since a wide variety of things require explanation, and since many different types of explanation exist, as more complex explanation is required. To facilitate the requirement leaves, least of mention, for us to consider by introduction a bit of technical terminology. The term 'explanation' is used to refer to that which is to be explained: The term 'explanans' refer to that which does the explaining, the explanans and the explanation taken together constitute the explanation.

One common type of explanation occurs when deliberate human actions are explained in terms of conscious purposes. 'Why did you go to the pharmacy yesterday?' 'Because I had a headache and needed to get some aspirin.' It is tacitly assumed that aspirin is an appropriate medication for headaches and that going to the pharmacy would be an efficient way of getting some. Such explanations are, of course, teleological, referring, ss they do, to goals. The explanans are not the realisation of a future goal - if the pharmacy happened to be closed for stocktaking the aspirin would have been obtained there, bu t that would not invalidate the explanation. Some philosophers would say that the antecedent desire to achieve the end is what doers the explaining: Others might say that the explaining is done by the nature of the goal and the fact that the action promoted the chances of realizing it. (Taylor, 1964). In that it should not be automatically being assumed that such explanations are causal. Philosophers differ considerably on whether these explanations are to be framed in terms of cause or reason, but the distinction cannot be used to show that the relation between reasons and the actions they justify is in no way causal, and there are many differing analyses of such concepts as intention and agency. Expanding the domain beyond consciousness, Freud maintained, in addition, that much human behaviour can be explained in terms of unconscious and conscious wishes. Those Freudian explanations should probably be construed as basically causal.

Problems arise when teleological explanations are offered in other context. The behaviour of non-human animals is often explained in terms of purpose, e.g., the mouse ran to escape from the cat. In such cases the existence of conscious purpose seems dubious. The situation is still more problematic when a supr-empirical purpose in invoked, e.g., the explanations of living species in terms of God's purpose, or the vitalistic explanations of biological phenomena in terms of a entelechy or vital principle. In recent years an 'anthropic principle' has received attention in cosmology (Barrow and Tipler, 1986). All such explanations have been condemned by many philosophers an anthropomorphic.

Nevertheless, philosophers and scientists often maintain that functional explanations play an important an legitimate role in various sciences such as, evolutionary biology, anthropology and sociology. For example, of the peppered moth in Liverpool, the change in colour from the light phase to the dark phase and back again to the light phase provided adaption to a changing environment and fulfilled the function of reducing predation on the spacies. In the study of primitive soviets anthropologists have insisted that various rituals the (rain dance) which may be inefficacious in braining about their manifest goals (producing rain), actually cohesion at a period of stress (often a drought). Philosophers who admit teleological and/or functional explanations in common sense and science oftentimes take pans to argue that such explanations can be annualized entirely in terms of efficient causes, thereby escaping the charge of anthropomorphism (Wright, 1976): Again, however, not all philosophers agree.

Causal theories of Propositional knowledge differ over whether they deviate from the tripartite analysis by dropping the requirements that one's believing (accepting) that 'h' be justified. The same variation occurs regarding reliability theories, which present the Knower as reliable concerning the issue of whether or not 'h', in the sense that some of one's cognitive or epistemic states, θ, are such that, given further characteristics of oneself-possibly including relations to factors external to one and which one may not be aware-it is nomologically necessary (or at least probable) that 'h'. In some versions, the reliability is required to be 'global' in as far as it must concern a nomologically (probabilistic-relationship) relationship that states of type θ to the acquisition of true beliefs about a wider range of issues than merely whether or not 'h'. There is also controversy about how to delineate the limits of what constitutes a type of relevant personal state or characteristic. (For example, in a case where Mr Notgot has not been shamming and one does know thereby that someone in the office owns a Ford, such as a way of forming beliefs about the properties of persons spatially close to one, or instead something narrower, such as a way of forming beliefs about Ford owners in offices partly upon the basis of their relevant testimony?)

One important variety of reliability theory is a conclusive reason account, which includes a requirement that one's reasons for believing that 'h' be such that in one's circumstances, if h* were not to occur then, e.g., one would not have the reasons one does for believing that 'h', or, e.g., one would not believe that 'h'. Roughly, the latter is demanded by theories that treat a Knower as 'tracking the truth', theories that include the further demand that is roughly, if it were the case, that 'h', then one would believe that 'h'. A version of the tracking theory has been defended by Robert Nozick (1981), who adds that if what he calls a 'method' has been used to arrive at the belief that 'h', then the antecedent clauses of the two conditionals that characterize tracking will need to include the hypothesis that one would employ the very same method.

But unless more conditions are added to Nozick's analysis, it will be too weak to explain why one lack's knowledge in a version of the last variant of the tricky Mr Notgot case described above, where we add the following details: (a) Mr Notgot's compulsion is not easily changed, (b) while in the office, Mr Notgot has no other easy trick of the relevant type to play on one, and finally for one's belief that 'h', not by reasoning through a false belief ut by basing belief that 'h', upon a true existential generalization of one's evidence.

Nozick's analysis is in addition too strong to permit anyone ever to know that 'h': 'Some of my beliefs about beliefs might be otherwise, e.g., I might have rejected on of them'. If I know that 'h5' then satisfaction of the antecedent of one of Nozick's conditionals would involve its being false that 'h5', thereby thwarting satisfaction of the consequent's requirement that I not then believe that 'h5'. For the belief that 'h5' is itself one of my beliefs about beliefs (Shope, 1984).

Some philosophers think that the category of knowing for which is true. Justified believing (accepting) is a requirement constituting only a species of Propositional knowledge, construed as an even broader category. They have proposed various examples of 'PK' that do not satisfy the belief and/or justification conditions of the tripartite analysis. Such cases are often recognized by analyses of Propositional knowledge in terms of powers, capacities, or abilities. For instance, Alan R. White (1982) treats 'PK' as merely the ability to provide a correct answer to a possible question. White may be equating 'producing' knowledge in the sense of producing 'the correct answer to a possible question' with 'displaying' knowledge in the sense of manifesting knowledge. (White, 1982). The latter can be done even by very young children and some non-human animals independently of their being asked questions, understanding questions, or recognizing answers to questions. Indeed, an example that has been proposed as an instance of knowing that 'h' without believing or accepting that 'h' can be modified so as to illustrate this point. Two examples concerns an imaginary person who has no special training or information about horses or racing, but who in an experiment persistently and correctly picks the winners of upcoming horseraces. If the example is modified so that the hypothetical 'seer' never picks winners but only muses over whether those horses wight win, or only reports those horses winning, this behaviour should be as much of a candidate for the person's manifesting knowledge that the horse in question will win as would be the behaviour of picking it as a winner.

These considerations expose limitations in Edward Craig's analysis (1990) of the concept of knowing of a person's being a satisfactory informants in relation to an inquirer who wants to find out whether or not 'h'. Craig realizes that counterexamples to his analysis appear to be constituted by Knower who are too recalcitrant to inform the inquirer, or too incapacitate to inform, or too discredited to be worth considering (as with the boy who cried 'Wolf'). Craig admits that this might make preferable some alternative view of knowledge as a different state that helps to explain the presence of the state of being a suitable informant when the latter does obtain. Such the alternate, which offers a recursive definition that concerns one's having the power to proceed in a way representing the state of affairs, causally involved in one's proceeding in this way. When combined with a suitable analysis of representing, this theory of propositional knowledge can be unified with a structurally similar analysis of knowing how to do something.

Knowledge and belief, according to most epistemologists, knowledge entails belief, so that I cannot know that such and such is the case unless I believe that such and such is the case. Others think this entailment thesis can be rendered more accurately if we substitute for belief some closely related attitude. For instance, several philosophers would prefer to say that knowledge entail psychological certainties (Prichard, 1950 and Ayer, 1956) or conviction (Lehrer, 1974) or acceptance (Lehrer, 1989). Nonetheless, there are arguments against all versions of the thesis that knowledge requires having a belief-like attitude toward the known. These arguments are given by philosophers who think that knowledge and belief (or a facsimile) are mutually incompatible (the incomparability thesis), or by ones who say that knowledge does not entail belief, or vice versa, so that each may exist without the other, but the two may also coexist (the separability thesis).

The incompatibility thesis is sometimes traced to Plato (429-347 Bc) in view of his claim that knowledge is infallible while belief or opinion is fallible ('Republic' 476-9). But this claim would not support the thesis. Belief might be a component of an infallible form of knowledge in spite of the fallibility of belief. Perhaps, knowledge involves some factor that compensates for the fallibility of belief.

A. Duncan-Jones (1939: Also Vendler, 1978) cite linguistic evidence to back up the incompatibility thesis. He notes that people often say 'I do not believe she is guilty. I know she is' and the like, which suggest that belief rule out knowledge. However, as Lehrer (1974) indicates, the above exclamation is only a more emphatic way of saying 'I do not just believe she is guilty, I know she is' where 'just' makes it especially clear that the speaker is signalling that she has something more salient than mere belief, not that she has something inconsistent with belief, namely knowledge. Compare: 'You do not hurt him, you killed him.'

H.A. Prichard (1966) offers a defence of the incompatibility thesis that hinges on the equation of knowledge with certainty (both infallibility and psychological certitude) and the assumption that when we believe in the truth of a claim we are not certain about its truth. Given that belief always involves uncertainty while knowledge never dies, believing something rules out the possibility of knowing it. Unfortunately, however, Prichard gives 'us' no goods reason to grant that states of belief are never ones involving confidence. Conscious beliefs clearly involve some level of confidence, to suggest that we cease to believe things about which we are completely confident is bizarre.

A.D. Woozley (1953) defends a version of the separability thesis. Woozley's version, which deals with psychological certainty rather than belief per se, is that knowledge can exist in the absence of confidence about the item known, although might also be accompanied by confidence as well. Woozley remarks that the test of whether I know something is 'what I can do, where what I can do may include answering questions.' On the basis of this remark he suggests that even when people are unsure of the truth of a claim, they might know that the claim is true. We unhesitatingly attribute knowledge to people who give correct responses on examinations even if those people show no confidence in their answers. Woozley acknowledges, however, that it would be odd for those who lack confidence to claim knowledge. It would be peculiar to say, I am unsure that for whatever reason my answer is true: Still, I know it is correct But this tension Woozley explains using a distinction between conditions under which we are justified in making a claim (such as a claim to know something), and conditions under which the claim we make is true. While 'I know such and such' might be true even if I am unsure whether such and such holds, nonetheless it would be inappropriate for me to claim that I know that such and such unless I were sure of the truth of my claim.

Colin Radford (1966) extends Woozley's defence of the separability thesis. In Radford's view, not only is knowledge compatible with the lack of certainty, it is also compatible with a complete lack of belief. He argues by example. In one example, Jean has forgotten that he learned some English history year's priori and yet he is able to give several correct responses to questions such as 'When did the Battle of Hastings occur?' Since he forgot that he took history, he considers the correct response to be no more than guesses. Thus, when he says that the Battle of Hastings took place in 1066 he would deny having the belief that the Battle of Hastings took place in 1066. A disposition he would deny being responsible (or having the right to be convincing) that 1066 was the correct date. Radford would none the less insist that Jean know when the Battle occurred, since clearly be remembering the correct date. Radford admits that it would be inappropriate for Jean to say that he knew when the Battle of Hastings occurred, but, like Woozley he attributes the impropriety to a fact about when it is and is not appropriate to claim knowledge. When we claim knowledge, we ought, at least to believe that we have the knowledge we claim, or else our behaviour is 'intentionally misleading'.

Those that agree with Radford's defence of the separability thesis will probably think of belief as an inner state that can be detected through introspection. That Jean lack's beliefs about English history is plausible on this Cartesian picture since Jean does not find himself with any beliefs about English history when ne seek them out. One might criticize Radford, however, by rejecting that Cartesian view of belief. One could argue that some beliefs are thoroughly unconscious, for example. Or one could adopt a behaviourist conception of belief, such as Alexander Bain's (1859), according to which having beliefs is a matter of the way people are disposed to behave (and has not Radford already adopted a behaviourist conception of knowledge?) Since Jean gives the correct response when queried, a form of verbal behaviour, a behaviourist would be tempted to credit him with the belief that the Battle of Hastings occurred in 1066.

D.M. Armstrong (1873) takes a different tack against Radford. Jean does know that the Battle of Hastings took place in 1066. Armstrong will grant Radfod that point, in fact, Armstrong suggests that Jean believe that 1066 is not the date the Battle of Hastings occurred, for Armstrong equates the belief that such and such is just possible but no more than just possible with the belief that such and such is not the case. However, Armstrong insists, Jean also believes that the Battle did occur in 1066. After all, had Jean been mistaught that the Battle occurred in 1066, and subsequently 'guessed' that it took place in 1066, we would surely describe the situation as one in which Jean's false belief about the Battle became unconscious over time but persisted of a memory trace that was causally responsible for his guess. Out of consistency, we must describe Radford's original case as one that Jean's true belief became unconscious but persisted long enough to cause his guess. Thus, while Jean consciously believes that the Battle did not occur in 1066, unconsciously he does believe it occurred in 1066. So after all, Radford does not have a counterexample to the claim that knowledge entails belief.

Armstrong's response to Radford was to reject Radford's claim that the examinee lacked the relevant belief about English history. Another response is to argue that the examinee lacks the knowledge Radford attributes to him (cf. Sorenson, 1982). If Armstrong is correct in suggesting that Jean believes both that 1066 is and that it is not the date of the Battle of Hastings, one might deny Jean knowledge on the grounds that people who believe the denial of what they believe cannot be said t know the truth of their belief. Another strategy might be to compare the examine case with examples of ignorance given in recent attacks on externalist accounts of knowledge (needless to say. Externalists themselves would tend not to favour this strategy). Consider the following case developed by BonJour (1985): For no apparent reason, Samantha believes that she is clairvoyant. Again, for no apparent reason, she one day comes to believe that the President is in New York City, even though she has every reason to believe that the President is in Washington, D.C. In fact, Samantha is a completely reliable clairvoyant, and she has arrived at her belief about the whereabouts of the President thorough the power of her clairvoyance. Yet surely Samanthas belief is completely irrational. She is not justified in thinking what she does. If so, then she does not know where the President is. But Radford's examinee is unconventional. Even if Jean lacks the belief that Radford denies him, Radford does not have an example of knowledge that is unattended with belief. Suppose that Jean's memory had been sufficiently powerful to produce the relevant belief. As Radford says, in having every reason to suppose that his response is mere guesswork, and he has every reason to consider his belief false. His belief would be an irrational one, and hence one about whose truth Jean would be ignorant.

Least has been of mention to an approaching view from which 'perception' basis upon itself as a fundamental philosophical topic both for its central place in ant theory of knowledge, and its central place un any theory of consciousness. Philosophy in this area is constrained by a number of properties that we believe to hold of perception, (1) It gives 'us' knowledge of the world around 'us,' (2) We are conscious of that world by being aware of 'sensible qualities': Colour, sounds, tastes, smells, felt warmth, and the shapes and positions of objects in the environment. (3) Such consciousness is effected through highly complex information channels, such as the output of the three different types of colour-sensitive cells in the eye, or the channels in the ear for interpreting pulses of air pressure as frequencies of sound. (4) There ensues even more complex neurophysiological coding of that information, and eventually higher-order brain functions bring it about that we interpreted the information so received. (Much of this complexity has been revealed by the difficulties of writing programs enabling computers to recognize quite simple aspects of the visual scene.) The problem is to avoid thinking of here being a central, ghostly, conscious self, fed information in the same way that a screen if fed information by a remote television camera. Once such a model is in place, experience will seem like a veil getting between 'us' and the world, and the direct objects of perception will seem to be private items in an inner theatre or sensorium. The difficulty of avoiding this model is epically cute when we considered the secondary qualities of colour, sound, tactile feelings and taste, which can easily seem to have a purely private existence inside the perceiver, like sensation of pain. Calling such supposed items names like 'sense-data' or 'percepts' exacerbates the tendency, but once the model is in place, the first property, that perception gives 'us' knowledge of the world and its surrounding surfaces, is quickly threatened, for there will now seem little connection between these items in immediate experience and any independent reality. Reactions to this problem include 'scepticism' and 'idealism.'

A more hopeful approach is to claim that the complexities of (3) and (4) explain how we can have direct acquaintance of the world, than suggesting that the acquaintance we do have been at best indirect. It is pointed out that perceptions are not like sensation, precisely because they have a content, or outer-directed nature. To have a perception is to be aware of the world for being such-and-such a way, than to enjoy a mere modification of sensation. But such direct realism has to be sustained in the face of the evident personal (neurophysiological and other) factors determining how we perceive. One approach is to ask why it is useful to be conscious of what we perceive, when other aspects of our functioning work with information determining responses without any conscious awareness or intervention. A solution to this problem would offer the hope of making consciousness part of the natural world, than a strange optional extra.

Furthering, perceptual knowledge is knowledge acquired by or through the senses and includes most of what we know. We cross intersections when we see the light turn green, head for the kitchen when we smell the roast burning, squeeze the fruit to determine its ripeness, and climb out of bed when we hear the alarm ring. In each case we come to know something-that the light has turned green, that the roast is burning, that the melon is overripe, and that it is time to get up-by some sensory means. Seeing that the light has turned green is learning something-that, the light has turned green-by use of the eyes. Feeling that the melon is overripe is coming to know a fact-that the melon is overripe-by one's sense to touch. In each case the resulting knowledge is somehow based on, derived from or grounded in the sort of experience that characterizes the sense modality in question.

Much as much of our perceptual knowledge is indirect, dependent or derived. By this I mean that the facts we describe ourselves as learning, as coming to know, by perceptual means are pieces of knowledge that depend on our coming to know something else, some other fact, in a more direct way. We see, by the gauge, that we need gas, see, by the newspapers, that our team has lost again, see, by her expression, that she is nervous. This derived or dependent sort of knowledge is particularly prevalent in the cases of vision, but it occurs, to a lesser degree, in every sense modality. We install bells and other noise-makers so that we calm for example, hear (by the bell) that someone is at the door and (by the alarm) that its time to get up. When we obtain knowledge in this way, it is clear that unless one sees-hence, comes to know something about the gauge (that it says) and (hence, know) that one is described as coming to know by perceptual means. If one cannot hear that the bell is ringing, one cannot-in at least in this way-hear that one's visitors have arrived. In such cases one sees (hears, smells, etc.) that 'a' is 'F', coming to know thereby that 'a' is 'F', by seeing (hearing, etc.) that some other condition, 'b's' being 'G', obtains when this occurs, the knowledge (that 'a' is 'F') is derived from, or dependent on, the more basic perceptual knowledge that 'b' is 'G'.

And finally, the representational Theory of mind, (which goes back at least to Aristotle) takes as its starting point commonsense mental states, such as thoughts, beliefs, desires, perceptions and images. Such states are said to have 'intentionality' - they are about or refer to things, and may be evaluated with respect to properties like consistency, truth, appropriateness and accuracy. (For example, the thought that cousins are not related is inconsistent, the belief that Elvis is dead is true, the desire to eat the moon is inappropriate, a visual experience of a ripe strawberry as red is accurate, an image of George W. Bush with dreadlocks is inaccurate.)

The Representational Theory of Mind, defines such intentional mental states as relations to mental representations, and explains the intentionality of the former in terms of the semantic properties of the latter. For example, to believe that Elvis is dead is to be appropriately related to a mental representation whose propositional content is that Elvis is dead. (The desire that Elvis be dead, the fear that he is dead, the regret that he is dead, etc., involve different relations to the same mental representation.) To perceive a strawberry is to have a sensory experience of some kind which is appropriately related to (e.g., caused by) the strawberry Representational theory of mind also understands mental processes such as thinking, reasoning and imagining as sequences of intentional mental states. For example, to imagine the moon rising over a mountain is to entertain a series of mental images of the moon (and a mountain). To infer a proposition q from the proposition’s p and if 'p' then 'q' is (among other things) to have a sequence of thoughts of the form 'p', 'if p' then 'q', 'q'.

Contemporary philosophers of mind have typically supposed (or at least hoped) that the mind can be naturalized -, i.e., that all mental facts have explanations in the terms of natural science. This assumption is shared within cognitive science, which attempts to provide accounts of mental states and processes in terms (ultimately) of features of the brain and central nervous system. In the course of doing so, the various sub-disciplines of cognitive science (including cognitive and computational psychology and cognitive and computational neuroscience) postulate a number of different kinds of structures and processes, many of which are not directly implicated by mental states and processes as commonsensical conceived. There remains, however, a shared commitment to the idea that mental states and processes are to be explained in terms of mental representations.

In philosophy, recent debates about mental representation have centred around the existence of propositional attitudes (beliefs, desires, etc.) and the determination of their contents (how they come to be about what they are about), and the existence of phenomenal properties and their relation to the content of thought and perceptual experience. Within cognitive science itself, the philosophically relevant debates have been focussed on the computational architecture of the brain and central nervous system, and the compatibility of scientific and commonsense accounts of mentality.

Intentional Realists such as Dretske (e.g., 1988) and Fodor (e.g., 1987) note that the generalizations we apply in everyday life in predicting and explaining each other's behaviour (often collectively referred to as 'folk psychology') are both remarkably successful and indispensable. What a person believes, doubts, desires, fears, etc. is a highly reliable indicator of what that person will do. We have no other way of making sense of each other's behaviour than by ascribing such states and applying the relevant generalizations. We are thus committed to the basic truth of commonsense psychology and, hence, to the existence of the states its generalizations refer to. (Some realists, such as Fodor, also hold that commonsense psychology will be vindicated by cognitive science, given that propositional attitudes can be construed as computational relations to mental representations.)

Intentional Eliminativists, such as Churchland, (perhaps) Dennett and (at one time) Stich argue that no such things as propositional attitudes (and their constituent representational states) are implicated by the successful explanation and prediction of our mental lives and behaviour. Churchland denies that the generalizations of commonsense propositional-attitude psychology are true. He (1981) argues that folk psychology is a theory of the mind with a long history of failure and decline, and that it resists incorporation into the framework of modern scientific theories (including cognitive psychology). As such, it is comparable to alchemy and phlogiston theory, and ought to suffer a comparable fate. Commonsense psychology is false, and the states (and representations) it postulates simply don't exist. (It should be noted that Churchland is not an eliminativist about mental representation tout court.

Dennett (1987) grants that the generalizations of commonsense psychology are true and indispensable, but denies that this is sufficient reason to believe in the entities they appear to refer to. He argues that to give an intentional explanation of a system's behaviour is merely to adopt the 'intentional stance' toward it. If the strategy of assigning contentful states to a system and predicting and explaining its behaviour (on the assumption that it is rational -, i.e., that it behaves as it should, given the propositional attitudes it should have in its environment) is successful, then the system is intentional, and the propositional-attitude generalizations we apply to it are true. But there is nothing more to having a propositional attitude than this.

Though he has been taken to be thus claiming that intentional explanations should be construed instrumentally, Dennett (1991) insists that he is a 'moderate' realist about propositional attitudes, since he believes that the patterns in the behaviour and behavioural dispositions of a system on the basis of which we (truly) attribute intentional states to it are objectively real. In the event that there are two or more explanatorily adequate but substantially different systems of intentional ascriptions to an individual, however, Dennett claims there is no fact of the matter about what the system believes (1987, 1991). This does suggest an irrealism at least with respect to the sorts of things Fodor and Dretske take beliefs to be; though it is not the view that there is simply nothing in the world that makes intentional explanations true.

(Davidson 1973, 1974 and Lewis 1974 also defend the view that what it is to have a propositional attitude is just to be interpretable in a particular way. It is, however, not entirely clear whether they intend their views to imply irrealism about propositional attitudes.). Stich (1983) argues that cognitive psychology does not (or, in any case, should not) taxonomize mental states by their semantic properties at all, since attribution of psychological states by content is sensitive to factors that render it problematic in the context of a scientific psychology. Cognitive psychology seeks causal explanations of behaviour and cognition, and the causal powers of a mental state are determined by its intrinsic 'structural' or 'syntactic' properties. The semantic properties of a mental state, however, are determined by its extrinsic properties -, e.g., its history, environmental or intra-mental relations. Hence, such properties cannot figure in causal-scientific explanations of behaviour. (Fodor 1994 and Dretske 1988 are realist attempts to come to grips with some of these problems.) Stich proposes a syntactic theory of the mind, on which the semantic properties of mental states play no explanatory role.

It is a traditional assumption among realists about mental representations that representational states come in two basic varieties (Boghossian 1995). There are those, such as thoughts, which are composed of concepts and have no phenomenal ('what-it's-like') features ('qualia'), and those, such as sensory experiences, which have phenomenal features but no conceptual constituents. (Non-conceptual content is usually defined as a kind of content that states of a creature lacking concepts but, nonetheless enjoy. On this taxonomy, mental states can represent either in a way analogous to expressions of natural languages or in a way analogous to drawings, paintings, maps or photographs. (Perceptual states such as seeing that something is blue, are sometimes thought of as hybrid states, consisting of, for example, a Non-conceptual sensory experience and a thought, or some more integrated compound of sensory and conceptual components.)

Some historical discussions of the representational properties of mind (e.g., Aristotle 1984, Locke 1689/1975, Hume 1739/1978) seem to assume that Non-conceptual representations - percepts ('impressions'), images ('ideas') and the like - are the only kinds of mental representations, and that the mind represents the world in virtue of being in states that resemble things in it. On such a view, all representational states have their content in virtue of their phenomenal features. Powerful arguments, however, focussing on the lack of generality (Berkeley 1975), ambiguity (Wittgenstein 1953) and non-compositionality (Fodor 1981) of sensory and imagistic representations, as well as their unsuitability to function as logical (Frége 1918/1997, Geach 1957) or mathematical (Frége 1884/1953) concepts, and the symmetry of resemblance (Goodman 1976), convinced philosophers that no theory of mind can get by with only Non-conceptual representations construed in this way.

Contemporary disagreement over Non-conceptual representation concerns the existence and nature of phenomenal properties and the role they play in determining the content of sensory experience. Dennett (1988), for example, denies that there are such things as qualia at all; while Brandom (2002), McDowell (1994), Rey (1991) and Sellars (1956) deny that they are needed to explain the content of sensory experience. Among those who accept that experiences have phenomenal content, some (Dretske, Lycan, Tye) argue that it is reducible to a kind of intentional content, while others (Block, Loar, Peacocke) argue that it is irreducible.

The representationalist thesis is often formulated as the claim that phenomenal properties are representational or intentional. However, this formulation is ambiguous between a reductive and a non-deductive claim (though the term 'representationalism' is most often used for the reductive claim). On one hand, it could mean that the phenomenal content of an experience is a kind of intentional content (the properties it represents). On the other, it could mean that the (irreducible) phenomenal properties of an experience determine an intentional content. Representationalists such as Dretske, Lycan and Tye would assent to the former claim, whereas phenomenalists such as Block, Chalmers, Loar and Peacocke would assent to the latter. (Among phenomenalists, there is further disagreement about whether qualia are intrinsically representational (Loar) or not (Block, Peacocke).

Most (reductive) representationalists are motivated by the conviction that one or another naturalistic explanation of intentionality is, in broad outline, correct, and by the desire to complete the naturalization of the mental by applying such theories to the problem of phenomenality. (Needless to say, most phenomenalists (Chalmers is the major exception) are just as eager to naturalize the phenomenal - though not in the same way.)

The main argument for representationalism appeals to the transparency of experience. The properties that characterize what it's like to have a perceptual experience are presented in experience as properties of objects perceived: in attending to an experience, one seems to 'see through it' to the objects and properties it is experiences of. They are not presented as properties of the experience itself. If nonetheless they were properties of the experience, perception would be massively deceptive. But perception is not massively deceptive. According to the representationalist, the phenomenal character of an experience is due to its representing objective, non-experiential properties. (In veridical perception, these properties are locally instantiated; in illusion and hallucination, they are not.) On this view, introspection is indirect perception: one comes to know what phenomenal features one's experience has by coming to know what objective features it represents.

In order to account for the intuitive differences between conceptual and sensory representations, representationalists appeal to their structural or functional differences. Dretske (1995), for example, distinguishes experiences and thoughts on the basis of the origin and nature of their functions: an experience of a property 'P' is a state of a system whose evolved function is to indicate the presence of 'P' in the environment; a thought representing the property 'P', on the other hand, is a state of a system whose assigned (learned) function is to calibrate the output of the experiential system. Rey (1991) takes both thoughts and experiences to be relations to sentences in the language of thought, and distinguishes them on the basis of (the functional roles of) such sentences' constituent predicates. Lycan (1987, 1996) distinguishes them in terms of their functional-computational profiles. Tye (2000) distinguishes them in terms of their functional roles and the intrinsic structure of their vehicles: thoughts are representations in a language-like medium, whereas experiences are image-like representations consisting of 'symbol-filled arrays.' (The account of mental images in Tye 1991.)

Phenomenalists tend to make use of the same sorts of features (function, intrinsic structure) in explaining some of the intuitive differences between thoughts and experiences; but they do not suppose that such features exhaust the differences between phenomenal and non-phenomenal representations. For the phenomenalist, it is the phenomenal properties of experiences - qualia themselves - that constitute the fundamental difference between experience and thought. Peacocke (1992), for example, develops the notion of a perceptual 'scenario' (an assignment of phenomenal properties to coordinates of a three-dimensional egocentric space), whose content is 'correct' (a semantic property) if in the corresponding 'scene' (the portion of the external world represented by the scenario) properties are distributed as their phenomenal analogues are in the scenario.

Another sort of representation championed by phenomenalists (e.g., Block, Chalmers (2003) and Loar (1996)) is the 'phenomenal concept' -, a conceptual/phenomenal hybrid consisting of a phenomenological 'sample' (an image or an occurrent sensation) integrated with (or functioning as) a conceptual component. Phenomenal concepts are postulated to account for the apparent fact (among others) that, as McGinn (1991) puts it, 'you cannot form [introspective] concepts of conscious properties unless you yourself instantiate those properties.' One cannot have a phenomenal concept of a phenomenal property 'P', and, hence, phenomenal beliefs about P, without having experience of 'P', because 'P' itself is (in some way) constitutive of the concept of 'P'. (Jackson 1982, 1986 and Nagel 1974.)

Though imagery has played an important role in the history of philosophy of mind, the important contemporary literature on it is primarily psychological. In a series of psychological experiments done in the 1970s (summarized in Kosslyn 1980 and Shepard and Cooper 1982), subjects' response time in tasks involving mental manipulation and examination of presented figures was found to vary in proportion to the spatial properties (size, orientation, etc.) of the figures presented. The question of how these experimental results are to be explained has kindled a lively debate on the nature of imagery and imagination.

Kosslyn (1980) claims that the results suggest that the tasks were accomplished via the examination and manipulation of mental representations that they have spatial properties, i.e., pictorial representations, or images. Others, principally Pylyshyn (1979, 1981, 2003), argue that the empirical facts can be explained in terms exclusively of discursive, or propositional representations and cognitive processes defined over them. (Pylyshyn takes such representations to be sentences in a language of thought.)

The idea that pictorial representations are literally pictures in the head is not taken seriously by proponents of the pictorial view of imagery. The claim is, rather, that mental images represent in a way that is relevantly like the way pictures represent. (Attention has been focussed on visual imagery - hence the designation 'pictorial'; Though of course, there may imagery in other modalities - auditory, olfactory, etc. - as well.)

The distinction between pictorial and discursive representation can be characterized in terms of the distinction between analog and digital representation (Goodman 1976). This distinction has itself been variously understood (Fodor & Pylyshyn 1981, Goodman 1976, Haugeland 1981, Lewis 1971, McGinn 1989), though a widely accepted construal is that analog representation is continuous (i.e., in virtue of continuously variable properties of the representation), while digital representation is discrete (i.e., in virtue of properties a representation either has or doesn't have) (Dretske 1981). (An analog/digital distinction may also be made with respect to cognitive processes. (Block 1983.)) On this understanding of the analog/digital distinction, imagistic representations, which represent in virtue of properties that may vary continuously (such for being more or less bright, loud, vivid, etc.), would be analog, while conceptual representations, whose properties do not vary continuously (a thought cannot be more or less about Elvis: either it is or it is not) would be digital.

It might be supposed that the pictorial/discursive distinction is best made in terms of the phenomenal/nonphenomenal distinction, but it is not obvious that this is the case. For one thing, there may be nonphenomenal properties of representations that vary continuously. Moreover, there are ways of understanding pictorial representation that presuppose neither phenomenality nor analogicity. According to Kosslyn (1980, 1982, 1983), a mental representation is 'quasi-pictorial' when every part of the representation corresponds to a part of the object represented, and relative distances between parts of the object represented are preserved among the parts of the representation. But distances between parts of a representation can be defined functionally rather than spatially - for example, in terms of the number of discrete computational steps required to combine stored information about them. (Rey 1981.)

Tye (1991) proposes a view of images on which they are hybrid representations, consisting both of pictorial and discursive elements. On Tye's account, images are '(labelled) interpreted symbol-filled arrays.' The symbols represent discursively, while their arrangement in arrays has representational significance (the location of each 'cell' in the array represents a specific viewer-centred 2-D location on the surface of the imagined object)

The contents of mental representations are typically taken to be abstract objects (properties, relations, propositions, sets, etc.). A pressing question, especially for the naturalist, is how mental representations come to have their contents. Here the issue is not how to naturalize content (abstract objects can't be naturalized), but, rather, how to provide a naturalistic account of the content-determining relations between mental representations and the abstract objects they express. There are two basic types of contemporary naturalistic theories of content-determination, causal-informational and functional.

Causal-informational theories hold that the content of a mental representation is grounded in the information it carries about what does (Devitt 1996) or would (Fodor 1987, 1990) cause it to occur. There is, however, widespread agreement that causal-informational relations are not sufficient to determine the content of mental representations. Such relations are common, but representation is not. Tree trunks, smoke, thermostats and ringing telephones carry information about what they are causally related to, but they do not represent (in the relevant sense) what they carry information about. Further, a representation can be caused by something it does not represent, and can represent something that has not caused it.

The main attempts to specify what makes a causal-informational state a mental representation are Asymmetric Dependency Theories, the Asymmetric Dependency Theory distinguishes merely informational relations from representational relations on the basis of their higher-order relations to each other: informational relations depend upon representational relations, but not vice-versa. For example, if tokens of a mental state type are reliably caused by horses, cows-on-dark-nights, zebras-in-the-mist and Great Danes, then they carry information about horses, etc. If, however, such tokens are caused by cows-on-dark-nights, etc. because they were caused by horses, but not vice versa, then they represent horses.

According to Teleological Theories, representational relations are those a representation-producing mechanism has the selected (by evolution or learning) function of establishing. For example, zebra-caused horse-representations do not mean zebra, because the mechanism by which such tokens are produced has the selected function of indicating horses, not zebras. The horse-representation-producing mechanism that responds to zebras is malfunctioning.

Functional theories, hold that the content of a mental representation are well grounded in causal computational inferential relations to other mental portrayals other than mental representations. They differ on whether relata should include all other mental representations or only some of them, and on whether to include external states of affairs. The view that the content of a mental representation is determined by its inferential/computational relations with all other representations is holism; the view it is determined by relations to only some other mental states is localisms (or molecularism). (The view that the content of a mental state depends on none of its relations to other mental states is atomism.) Functional theories that recognize no content-determining external relata have been called solipsistic (Harman 1987). Some theorists posit distinct roles for internal and external connections, the former determining semantic properties analogous to sense, the latter determining semantic properties analogous to reference (McGinn 1982, Sterelny 1989)

(Reductive) representationalists (Dretske, Lycan, Tye) usually take one or another of these theories to provide an explanation of the (Non-conceptual) content of experiential states. They thus tend to be Externalists (see the next section) about phenomenological as well as conceptual content. Phenomenalists and non-deductive representationalists (Block, Chalmers, Loar, Peacocke, Siewert), on the other hand, take it that the representational content of such states is (at least in part) determined by their intrinsic phenomenal properties. Further, those who advocate a phenomenology-based approach to conceptual content (Horgan and Tiensen, Loar, Pitt, Searle, Siewert) also seem to be committed to internalist individuation of the content (if not the reference) of such states.

Generally, those who, like informational theorists, think relations to one's (natural or social) environment are (at least partially) determinative of the content of mental representations are Externalists (e.g., Burge 1979, 1986, McGinn 1977, Putnam 1975), whereas those who, like some proponents of functional theories, think representational content is determined by an individual's intrinsic properties alone, are internalists (or individualists).

This issue is widely taken to be of central importance, since psychological explanation, whether commonsense or scientific, is supposed to be both causal and content-based. (Beliefs and desires cause the behaviours they do because they have the contents they do. For example, the desire that one have a beer and the beliefs that there is beer in the refrigerator and that the refrigerator is in the kitchen may explain one's getting up and going to the kitchen.) If, however, a mental representation's having a particular content is due to factors extrinsic to it, it is unclear how its having that content could determine its causal powers, which, arguably, must be intrinsic. Some who accept the standard arguments for externalism have argued that internal factors determine a component of the content of a mental representation. They say that mental representations have both 'narrow' content (determined by intrinsic factors) and 'wide' or 'broad' content (determined by narrow content plus extrinsic factors). (This distinction may be applied to the sub-personal representations of cognitive science as well as to those of commonsense psychology.

Narrow content has been variously construed. Putnam (1975), Fodor (1982)), and Block (1986), for example, seem to understand it as something like dedictorial content (i.e., Frégean sense, or perhaps character, à la Kaplan 1989). On this construal, narrow content is context-independent and directly expressible. Fodor (1987) and Block (1986), however, have also characterized narrow content as radically inexpressible. On this construal, narrow content is a kind of proto-content, or content-determinant, and can be specified only indirectly, via specifications of context/wide-content pairings. Both, construe of as a narrow content and are characterized as functions from context to (wide) content. The narrow content of a representation is determined by properties intrinsic to it or its possessor such as its syntactic structure or its intra-mental computational or inferential role (or its phenomenology.

Burge (1986) has argued that causation-based worries about externalist individuation of psychological content, and the introduction of the narrow notion, are misguided. Fodor (1994, 1998) has more recently urged that a scientific psychology might not need narrow content in order to supply naturalistic (causal) explanations of human cognition and action, since the sorts of cases they were introduced to handle, viz., Twin-Earth cases and Frége cases, are nomologically either impossible or dismissible as exceptions to non-strict psychological laws.

The leading contemporary version of the Representational Theory of Mind, the Computational Theory of Mind, claims that the brain is a kind of computer and that mental processes are computations. According to the computational theory of mind, cognitive states are constituted by computational relations to mental representations of various kinds, and cognitive processes are sequences of such states. The computational theory of mind and the representational theory of mind, may by attempting to explain all psychological states and processes in terms of mental representation. In the course of constructing detailed empirical theories of human and animal cognition and developing models of cognitive processes’ implementable in artificial information processing systems, cognitive scientists have proposed a variety of types of mental representations. While some of these may be suited to be mental relata of commonsense psychological states, some - so-called 'subpersonal' or 'sub-doxastic' representations - are not. Though many philosophers believe that computational theory of mind can provide the best scientific explanations of cognition and behaviour, there is disagreement over whether such explanations will vindicate the commonsense psychological explanations of prescientific representational theory of mind.

According to Stich's (1983) Syntactic Theory of Mind, for example, computational theories of psychological states should concern themselves only with the formal properties of the objects those states are relations to. Commitment to the explanatory relevance of content, however, is for most cognitive scientists fundamental. That mental processes are computations, which computations are rule-governed sequences of semantically evaluable objects, and that the rules apply to the symbols in virtue of their content, are central tenets of mainstream cognitive science.

Explanations in cognitive science appeal to a many different kinds of mental representation, including, for example, the 'mental models' of Johnson-Laird 1983, the 'retinal arrays,' 'primal sketches' and '2½ -D sketches' of Marr 1982, the 'frames' of Minsky 1974, the 'sub-symbolic' structures of Smolensky 1989, the 'quasi-pictures' of Kosslyn 1980, and the 'interpreted symbol-filled arrays' of Tye 1991 - in addition to representations that may be appropriate to the explanation of commonsense

Psychological states. Computational explanations have been offered of, among other mental phenomena, belief.

The classicists hold that mental representations are symbolic structures, which typically have semantically evaluable constituents, and that mental processes are rule-governed manipulations of them that are sensitive to their constituent structure. The connectionists, hold that mental representations are realized by patterns of activation in a network of simple processors ('nodes') and that mental processes consist of the spreading activation of such patterns. The nodes themselves are, typically, not taken to be semantically evaluable; nor do the patterns have semantically evaluable constituents. (Though there are versions of Connectionism -, 'localist' versions - on which individual nodes are taken to have semantic properties (e.g., Ballard 1986, Ballard & Hayes 1984).) It is arguable, however, that localist theories are neither definitive nor representative of the Conceptionist program.

Classicists are motivated (in part) by properties thought seems to share with language. Jerry Alan Fodor's (1935-), Language of Thought Hypothesis, (Fodor 1975, 1987), according to which the system of mental symbols constituting the neural basis of thought is structured like a language, provides a well-worked-out version of the classical approach as applied to commonsense psychology. According to the language of a thought hypothesis, the potential infinity of complex representational mental states is generated from a finite stock of primitive representational states, in accordance with recursive formation rules. This combinatorial structure accounts for the properties of productivity and systematicity of the system of mental representations. As in the case of symbolic languages, including natural languages (though Fodor does not suppose either that the language of thought hypotheses explains only linguistic capacities or that only verbal creatures have this sort of cognitive architecture), these properties of thought are explained by appeal to the content of the representational units and their combinability into contentful complexes. That is, the semantics of both language and thought is compositional: the content of a complex representation is determined by the contents of its constituents and their structural configuration.

Connectionists are motivated mainly by a consideration of the architecture of the brain, which apparently consists of layered networks of interconnected neurons. They argue that this sort of architecture is unsuited to carrying out classical serial computations. For one thing, processing in the brain is typically massively parallel. In addition, the elements whose manipulation drive’s computation in Conceptionist networks (principally, the connections between nodes) are neither semantically compositional nor semantically evaluable, as they are on the classical approach. This contrast with classical computationalism is often characterized by saying that representation is, with respect to computation, distributed as opposed to local: representation is local if it is computationally basic; and distributed if it is not. (Another way of putting this is to say that for classicists mental representations are computationally atomic, whereas for connectionists they are not.)

Moreover, connectionists argue that information processing as it occurs in Conceptionist networks more closely resembles some features of actual human cognitive functioning. For example, whereas on the classical view learning involves something like hypothesis formation and testing (Fodor 1981), on the Conceptionist model it is a matter of evolving distribution of 'weight' (strength) on the connections between nodes, and typically does not involve the formulation of hypotheses regarding the identity conditions for the objects of knowledge. The Conceptionist network is 'trained up' by repeated exposure to the objects it is to learn to distinguish; and, though networks typically require many more exposures to the objects than do humans, this seems to model at least one feature of this type of human learning quite well.

Further, degradation in the performance of such networks in response to damage is gradual, not sudden as in the case of a classical information processor, and hence more accurately models the loss of human cognitive function as it typically occurs in response to brain damage. It is also sometimes claimed that Conceptionist systems show the kind of flexibility in response to novel situations typical of human cognition - situations in which classical systems are relatively 'brittle' or 'fragile.'

Some philosophers have maintained that Connectionism entails that there are no propositional attitudes. Ramsey, Stich and Garon (1990) have argued that if Conceptionist models of cognition are basically correct, then there are no discrete representational states as conceived in ordinary commonsense psychology and classical cognitive science. Others, however (e.g., Smolensky 1989), hold that certain types of higher-level patterns of activity in a neural network may be roughly identified with the representational states of commonsense psychology. Still others argue that language-of-thought style representation is both necessary in general and realizable within Conceptionist architectures, collect the central contemporary papers in the classicist/Conceptionist debate, and provides useful introductory material as well.

Whereas Stich (1983) accepts that mental processes are computational, but denies that computations are sequences of mental representations, others accept the notion of mental representation, but deny that computational theory of mind provides the correct account of mental states and processes.

Van Gelder (1995) denies that psychological processes are computational. He argues that cognitive systems are dynamic, and that cognitive states are not relations to mental symbols, but quantifiable states of a complex system consisting of (in the case of human beings) a nervous system, a body and the environment in which they are embedded. Cognitive processes are not rule-governed sequences of discrete symbolic states, but continuous, evolving total states of dynamic systems determined by continuous, simultaneous and mutually determining states of the systems components. Representation in a dynamic system is essentially information-theoretic, though the bearers of information are not symbols, but state variables or parameters.

Horst (1996), on the other hand, argues that though computational models may be useful in scientific psychology, they are of no help in achieving a philosophical understanding of the intentionality of commonsense mental states. Computational theory of mind attempts to reduce the intentionality of such states to the intentionality of the mental symbols they are relations to. But, Horst claims, the relevant notion of symbolic content is essentially bound up with the notions of convention and intention. So the computational theory of mind involves itself in a vicious circularity: the very properties that are supposed to be reduced are (tacitly) appealed to in the reduction.

To say that a mental object has semantic properties is, paradigmatically, to say that it may be about, or be true or false of, an object or objects, or that it may be true or false simpliciter. Suppose I think that you took to sniffing snuff. I am thinking about you, and if what I think of you (that they take snuff) is true of you, then my thought is true. According to representational theory of mind such states are to be explained as relations between agents and mental representations. To think that you take snuff is to token in some way a mental representation whose content is that ocelots take snuff. On this view, the semantic properties of mental states are the semantic properties of the representations they are relations to.

Linguistic acts seem to share such properties with mental states. Suppose I say that you take snuff. I am talking about you, and if what I say of you (that they take snuff) is true of them, then my utterance is true. Now, to say that you take snuff is (in part) to utter a sentence that means that you take snuff. Many philosophers have thought that the semantic properties of linguistic expressions are inherited from the intentional mental states they are conventionally used to express. On this view, the semantic properties of linguistic expressions are the semantic properties of the representations that are the mental relata of the states they are conventionally used to express.

It is also widely held that in addition to having such properties as reference, truth-conditions and truth - so-called extensional properties - expressions of natural languages also have intensional properties, in virtue of expressing properties or propositions - i.e., in virtue of having meanings or senses, where two expressions may have the same reference, truth-conditions or truth value, yet express different properties or propositions (Frége 1892/1997). If the semantic properties of natural-language expressions are inherited from the thoughts and concepts they express (or vice versa, or both), then an analogous distinction may be appropriate for mental representations.

Theories of representational content may be classified according to whether they are atomistic or holistic and according to whether they are externalistic or internalistic, whereby, emphasizing the priority of a whole over its parts. Furthermore, in the philosophy of language, this becomes the claim that the meaning of an individual word or sentence can only be understood in terms of its relation to an indefinitely larger body of language, such as à whole theory, or even a whole language or form of life. In the philosophy of mind a mental state similarly may be identified only in terms of its relations with others. Moderate holism may allow the other things besides these relationships also count; extreme holism would hold that a network of relationships is all that we have. A holistic view of science holds that experience only confirms or disconfirms large bodies of doctrine, impinging at the edges, and leaving some leeway over the adjustment that it requires.

Once, again, in the philosophy of mind and language, the view that what is thought, or said, or experienced, is essentially dependent on aspects of the world external to the mind of the subject. The view goes beyond holding that such mental states are typically caused by external factors, to insist that they could not have existed as they now do without the subject being embedded in an external world of a certain kind. It is these external relations that make up the essence or identify of the mental state. Externalism is thus opposed to the Cartesian separation of the mental from the physical, since that holds that the mental could in principle exist as it does even if there were no external world at all. Various external factors have been advanced as ones on which mental content depends, including the usage of experts, the linguistic, norms of the community. And the general causal relationships of the subject. In the theory of knowledge, externalism is the view that a person might know something by being suitably situated with respect to it, without that relationship being in any sense within his purview. The person might, for example, be very reliable in some respect without believing that he is. The view allows that you can know without being justified in believing that you know.

However, atomistic theories take a representation’s content to be something that can be specified independent entity of that representation’ s relations to other representations. What the American philosopher of mind, Jerry Alan Fodor (1935-) calls the crude causal theory, for example, takes a representation to be a
cow
- a menial representation with the same content as the word ‘cow’ - if its tokens are caused by instantiations of the property of being-a-cow, and this is a condition that places no explicit constraints on how
cow
’s must or might relate to other representations. Holistic theories contrasted with atomistic theories in taking the relations à representation bears to others to be essential to its content. According to functional role theories, a representation is a
cow
if it behaves like a
cow
should behave in inference.

Internalist theories take the content of a representation to be a matter determined by factors internal to the system that uses it. Thus, what Block (1986) calls ‘short-armed’ functional role theories are internalist. Externalist theories take the content of a representation to be determined, in part at least, by factors external to the system that uses it. Covariance theories, as well as telelogical theories that invoke an historical theory of functions, take content to be determined by ‘external’ factors. Crossing the atomist-holistic distinction with the internalist-externalist distinction.

Externalist theories (sometimes called non-individualistic theories) have the consequence that molecule for molecule identical cognitive systems might yet harbour representations with different contents. This has given rise to a controversy concerning ‘narrow’ content. If we assume some form of externalist theory is correct, then content is, in the first instance ‘wide’ content, i.e., determined in part by factors external to the representing system. On the other hand, it seems clear that, on plausible assumptions about how to individuate psychological capacities, internally equivalent systems must have the same psychological capacities. Hence, it would appear that wide content cannot be relevant to characterizing psychological equivalence. Since cognitive science generally assumes that content is relevant to characterizing psychological equivalence, philosophers attracted to externalist theories of content have sometimes attempted to introduce ‘narrow’ content, i.e., an aspect or kind of content that is equivalent internally equivalent systems. The simplest such theory is Fodor’s idea (1987) that narrow content is a function from contents (i.e., from whatever the external factors are) to wide contents.

All the same, what a person expresses by a sentence is often a function of the environment in which he or she is placed. For example, the disease I refer to by the term like ‘arthritis’, or the kind of tree I refer to as a ‘Maple’ will be defined by criteria of which I know next to nothing. This raises the possibility of imagining two persons in rather different environments, but in which everything appears the same to each of them. The wide content of their thoughts and sayings will be different if the situation surrounding them is appropriately different: ‘situation’ may include the actual objects they perceive or the chemical or physical kinds of object in the world they inhabit, or the history of their words, or the decisions of authorities on what counts as an example, of one of the terms they use. The narrow content is that part of their thought which remains identical, through their identity of the way things appear, regardless of these differences of surroundings. Partisans of wide content may doubt whether any content in this sense narrow, partisans of narrow content believer that it is the fundamental notion, with wide content being explicable in terms of narrow content plus context.

Even so, the distinction between facts and values has outgrown its name: it applies not only to matters of fact vs, matters of value, but also to statements that something is, vs. statements that something ought to be. Roughly, factual statements - ‘is statements’ in the relevant sense - represent some state of affairs as obtaining, whereas normative statements - evaluative, and deontic ones - attribute goodness to something, or ascribe, to an agent, an obligation to act. Neither distinction is merely linguistic. Specifying a book’s monetary value is making a factual statement, though it attributes a kind of value. ‘That is a good book’ expresses a valu judgement though the term ‘value’ is absent (nor would ‘valuable’ be synonymous with ‘good’). Similarly, ‘we are morally obligated to fight’ superficially expresses a statement, and ‘By all indications it ough to rain’ makes a kind of ought-claim; but the former is an ought-statement, the latter an (epistemic) is-statement.

Theoretical difficulties also beset the distinction. Some have absorbed values into facts holding that all value is instrumental, roughly, to have value is to contribute - in a factual analysable way - to something further which is (say) deemed desirable. Others have suffused facts with values, arguing that facts (and observations) are ‘theory-impregnated’ and contending that values are inescapable to theoretical choice. But while some philosophers doubt that fact/value distinctions can be sustained, there persists a sense of a deep difference between evaluating, or attributing an obligation and, on the other hand, saying how the world is.

Fact/value distinctions, may be defended by appeal to the notion of intrinsic value, as a thing has in itself and thus independently of its consequences. Roughly, a valu statement (proper) is an ascription of intrinsic value, one to the effect that a thing is to some degree good in itself. This leaves open whether ought-statements are implicitly value statements, but even if they imply that something has intrinsic value - e.g., moral value - they can be independently characterized, say by appeal to rules that provide (justifying) reasons for action. One might also ground the fact value distinction in the attributional (or even motivational) component apparently implied by the making of valuational or deontic judgements: Thus, ‘it is a good book, but that is no reason for a positive attribute towards it’ and ‘you ought to do it, but there is no reason to’ seem inadmissible, whereas, substituting, ‘an expensive book’ and ‘you will do it’ yields permissible judgements. One might also argue that factual judgements are the kind which are in principle appraisable scientifically, and thereby anchor the distinction on the factual side. This ligne is plausible, but there is controversy over whether scientific procedures are ‘value-free’ in the required way.

Philosophers differ regarding the sense, if any, in which epistemology is normative (roughly, valuational). But what precisely is at stake in this controversy is no clearly than the problematic fact/value distinction itself. Must epistemologists as such make judgements of value or epistemic responsibility? If epistemology is naturalizable, then even epistemic principles simply articulate under what conditions - say, appropriate perceptual stimulations - a belief is justified, or constitutes knowledge. Its standards of justification, then would be like standards of, e.g., resilience for bridges. It is not obvious, however, that there appropriate standards can be established without independent judgements that, say, a certain kind of evidence is good enough for justified belief (or knowledge). The most plausible view may be that justification is like intrinsic goodness, though it supervenes on natural properties, it cannot be analysed wholly in factuel statements.

Thus far, belief has been depicted as being all-or-nothing, however, as a resulting causality for which we have grounds for thinking it true, and, all the same, its acceptance is governed by epistemic norms, and, least of mention, it is partially subject to voluntary control and has functional affinities to belief. Still, the notion of acceptance, like that of degrees of belief, merely extends the standard picture, and does not replace it.

Traditionally, belief has been of epistemological interest in its propositional guise: ‘S’ believes that ‘p’, where ‘p’ is a reposition towards which an agent, ‘S’ exhibits an attitude of acceptance. Not all belief is of this sort. If I trust you to say, I believer you. And someone may believe in Mr. Radek, or in a free-market economy, or in God. It is sometimes supposed that all belief is ‘reducible’ to propositional belief, belief-that. Thus, my believing you might be thought a matter of my believing, is, perhaps, that what you say is true, and your belief in free markets or God, is a matter of your believing that free-market economies are desirable or that God exists.

Some philosophers have followed St. Thomas Aquinas (1225-74), in supposing that to believer in God is simply to believer that certain truths hold while others argue that belief-in is a distinctive attitude, on that includes essentially an element of trust. More commonly, belief-in has been taken to involve a combination of propositional belief together with some further attitude.

The moral philosopher Richard Price (1723-91) defends the claim that there are different sorts of belief-in, some, but not all reducible to beliefs-that. If you believer in God, you believer that God exists, that God is good, you believer that God is good, etc. But according to Price, your belief involves, in addition, a certain complex pro-attitude toward its object. Even so, belief-in outruns the evidence for the corresponding belief-that. Does this diminish its rationality? If belief-in presupposes believes-that, it might be thought that the evidential standards for the former must be, at least, as high as standards for the latter. And any additional pro-attitude might be thought to require a further layer of justification not required for cases of belief-that.

Belief-in may be, in general, less susceptible to alternations in the face of unfavourable evidence than belief-that. A believer who encounters evidence against God’s existence may remain unshaken in his belief, in part because the evidence does not bear on his pro-attitude. So long as this is united with his belief that God exists, and reasonably so - in a way that an ordinary propositional belief that would not.

The correlative way of elaborating on the general objection to justificatory externalism challenges the sufficiency of the various externalist conditions by citing cases where those conditions are satisfied, but where the believers in question seem intuitively not to be justified. In this context, the most widely discussed examples have to do with possible occult cognitive capacities, like clairvoyance. Considering the point in application once, again, to reliabilism, the claim is that to think that he has such a cognitive power, and, perhaps, even good reasons to the contrary, is not rational or responsible and therefore not epistemically justified in accepting the belief that result from his clairvoyance, dispite the fact that the reliablist condition is satisfied.

One sort of response to this latter sorts of an objection is to ‘bite the bullet’ and insist that such believers are in fact justified, dismissing the seeming intuitions to the contrary as latent internalist prejudice. A more widely adopted response attempts to impose additional conditions, usually of a roughly internalist sort, which will rule out the offending example, while stopping far of a full internalism. But, while there is little doubt that such modified versions of externalism can handle particular cases, as well enough to avoid clear intuitive implausibility, the usually problematic cases that they cannot handle, and also whether there is and clear motivation for the additional requirements other than the general internalist view of justification that externalist is committed to reject.

A view in this same general vein, one that might be described as a hybrid of internalism and externalism holds that epistemic justification requires that there is a justicatory factor that is cognitively accessible to the believer in question (though it need not be actually grasped), thus ruling out, e.g., a pure reliabilism. At the same time, however, though it must be objectively true that beliefs for which such a factor is available are likely to be true, in addition, the fact need not be in any way grasped or cognitively accessible to the believer. In effect, of the premises needed to argue that a particular belief is likely to be true, one must be accessible in a way that would satisfy at least weak internalism, the internalist will respond that this hybrid view is of no help at all in meeting the objection and has no belief nor is it held in the rational, responsible way that justification intuitively seems to require, for the believer in question, lacking one crucial premise, still has no reason at all for thinking that his belief is likely to be true.

An alternative to giving an externalist account of epistemic justification, one which may be more defensible while still accommodating many of the same motivating concerns, is to give an externalist account of knowledge directly, without relying on an intermediate account of justification. Such a view will obviously have to reject the justified true belief account of knowledge, holding instead that knowledge is true belief which satisfies the chosen externalist condition, e.g., a result of a reliable process (and perhaps, further conditions as well). This makes it possible for such a view to retain internalist account of epistemic justification, though the centrality of that concept to epistemology would obviously be seriously diminished.

Such an externalist account of knowledge can accommodate the commonsense conviction that animals, young children, and unsophisticated adults’ posse’s knowledge, though not the weaker conviction (if such a conviction does exist) that such individuals are epistemically justified in their beliefs. It is, at least, less vulnerable to internalist counter-examples of the sort discussed, since the intuitions involved there pertain more clearly to justification than to knowledge. What is uncertain is what ultimate philosophical significance the resulting conception of knowledge, for which is accepted or advanced as true or real on the basis of less than conclusive evidence, as can only be assumed to have. In particular, does it have any serious bearing on traditional epistemological problems and on the deepest and most troubling versions of scepticism, which seems in fact to be primarily concerned with justification, and knowledge?`

A rather different use of the terms ‘internalism’ and ‘externalism’ have to do with the issue of how the content of beliefs and thoughts is determined: According to an internalist view of content, the content of such intention states depends only on the non-relational, internal properties of the individual’s mind or grain, and not at all on his physical and social environment: While according to an externalist view, content is significantly affected by such external factors and suggests a view that appears of both internal and external elements are standardly classified as an external view.

As with justification and knowledge, the traditional view of content has been strongly internalist in character. The main argument for externalism derives from the philosophy y of language, more specifically from the various phenomena pertaining to natural kind terms, indexicals, etc. that motivate the views that have come to be known as ‘direct reference’ theories. Such phenomena seem at least to show that the belief or thought content that can be properly attributed to a person is dependant on facts about his environment, e.g., whether he is on Earth or Twin Earth, what is fact pointing at, the classificatory criterion employed by expects in his social group, etc. - not just on what is going on internally in his mind or brain.

An objection to externalist account of content is that they seem unable to do justice to our ability to know the content of our beliefs or thought ‘from the inside’, simply by reflection. If content is depending on external factors pertaining to the environment, then knowledge of content should depend on knowledge of these factors - which will not in general be available to the person whose belief or thought is in question.

The adoption of an externalist account of mental content would seem to support an externalist account of justification, apart from all contentful representation is a belief inaccessible to the believer, then both the justifying statuses of other beliefs in relation to that of the same representation are the status of that content, being totally rationalized by further beliefs for which it will be similarly inaccessible. Thus, contravening the internalist requirement for justification. An internalist must insist that there are no justification relations of these sorts, that our internally associable content can also not be warranted or as stated or indicated without the deviated departure from a course or procedure or from a norm or standard in showing no deviation from traditionally held methods of justification exacting by anything else: But such a response appears lame unless it is coupled with an attempt to show that the externalist account of content is mistaken.

At the onset, its position is summed by the term of Cartesianism, the name given to the philosophical movement inaugurated by René Descartes (after’Caetesius,’ the Latin version). The main features of Cartesianism are (1) the use of methodical doubt as a tool for testing beliefs and reaching certainty, (2) a metaphysical system that starts from the subject’s indubitable awareness of his own existence; (3) a theory of ‘clear and distinct ideas’ based on the innate ideas and propositions implanted in the soul by God (these include the ideas of mathematics, which Descartes takes to be the fundamental building blocks of science); (4) The theories now known as ‘dualism’ - in that, there are two incompatible kinds of substance in the universe, mind (or thinking asymmetry) and matter (or extended substance). A corollary of this last theory is that human bings heterogeneously vary among composites of the unexceeded, immaterial consciousness united to a piece of purely physical machinery -the body. Another element in Cartesian dualism is the claim that the mind has perfect and transparent awareness of its own nature or essence.

The self conceived issues that Descartes presented in the first two Meditations: Aware only of its own thoughts, and capable of disembodied existence, neither in a space nor surrounded by others. This is the pure self or the ‘I’ that we are tempted to imagine as a simple unique thing that makes up our essential identity. Descartes’s view that he could keep hold of this nugget while doubting Lichtenberg and Kant criticize everything else, and most subsequent philosophers of mind.

For many people understanding their place of mind and in nature are the greatest philosophical problem. Mind is often thought to be the last domain that stubbornly resists scientific understanding, and philosophers differ over whether they fin that a cause for celebrating or scandals, Descartes gave the mind-body problem in the modern era its definitive shape, although the dualism that he espoused is far more widespread and far older, occurring in some form wherever there is a religious or philosophical tradition under which the soul may have an existence apart from the body. While most modern philosophies of mind would reject the imaginings that lead us to think that this makes sense, there is no consensus over the best way to integrate our understanding of people as bearers of physical properties on the one hand, as subjects of mental lives on the other.

The affixed nature of the philosophy of mind seeks to answer such questions as: Is mind distinct from matter? Can we define what it I to be conscious, and can we give principled reasons for deciding whether other creatures are conscious, or whether machines might be made so that thy being conscious? What is thinking, feeling, expedience, remembering? Is it useful to divide the functions of the mind up, separating memory from intelligence, rationality from sentiment, or do mental functions form an integrated whole? The dominant philosophies of mind in the current western tradition include varieties of physicalism and functionalism.

Still, the belief that philosophy of language is had informed much philosophy, especially in the 20th century, the fundamental basis of all philosophical problems, in that language is the distinctive exercise of mind, and the distinctive way in which we give shape to metaphysical beliefs. Particular topics will be made up of the division between syntax and semantics, and problems of understanding the number and nature of specifically semantic relationships, such ad meaning, reference, predication, and quantification. Pragmatics includes the theory of speech acts, while problems of rule-following and the indeterminacy of translation infects philosophies of both pragmatics and semantics.

During our intervening time, it is said of René Descartes (1596-1650) who was a French pphilosopher, scientist and mathematician. Descartes is often called the ‘father of modern philosophy,’ since he made epistemological questions the primary and central questions of the discipline. Nonetheless, this is misleading for several reasons. In the first place, Descartes’ conception of philosophy was very different from our own. The term ‘philosophy’ in the seventeenth century was far more comprehensive than it is today, and embraced the whole of what e nowadays call natural science, including cosmology, and physics, with subjects like anatomy, optics and medicine. Desecrates’ reputation as a ‘philosopher’ in his own time was based in these scientific areas. In the second place, even in those Cartesian writings that are philosophical in the modern academic sense, the epistemological concerns are different from the conceptual and linguistic inquires that characterize present-day ‘theory of knowledge.’ Descartes saw the need to base his scientific system on secure metaphysical foundations; by ‘metaphysical’ he meant inquires into ‘God and the soul and in general, all the first things to be discovered by philosophizing.’ These foundational inquiries included, to be sure. Questions about knowledge and certainty, but even here, Descartes is not primarily concerned with the criteria for knowledge claims, or with definitions of the epistemic concerns involved; his aim, is to provide a unified framework for understanding the universe. In place of the fragmented scholastic world of separate disciplines, each with its own methods and standards of precision, he aimed to construct a coherent theory of the world and man’s place within it. And this project required him ‘once in his life’ systematically to test all his former beliefs, and ti subject them to radical scrutiny, to see whether he could ‘establish’ anything at all in the science that was stable and likely to last

Briefly, Descartes’ views on knowledge were conditioned by the time in which he lived, which had witnessed a gradual erosion of beliefs held for centuries and apparently based on straightforward observation and ‘common sense.’ The most notable example of this was a long-held conviction, bolstered by the authority of the Church, hat an immovable earth was the centre of the universe. Galileo’s discovery of the moons of Jupiter (made when Descartes was a nine-year-old pupil at La Flèche) was but one piece in a mounting pile of evidence suggesting that the traditional view was radically mistaken. Descartes became obsessed by the thought that no lasting progress could be made in the sciences unless a systematic method could be devised for sifting through our preconceived opinions and establishing which of them, if mine, it was reliable. ‘Suppose we had a basket full of apples and were worried that some of them were rotten. How would be we proceed? Would we not begin by tipping the whole lot out and then pick up and put back only those we saw to be sound?’ Descartes’ ‘’Method of Doubt’ involved a determined effort to test our preconceived opinions or ‘prejudices’ to the limit, by applying a series of deliberate sceptical techniques (often derived from classical arguments for doubt that had ben revived in the sixteenth century). He points out first, that the senses (sight, hearing, touch, etc.) are often unreliable, and ‘never trusting entirely those who have deceived us is even prudent once’ (First Meditation); later, he cited such instances as the straight stick that looks bent in water, and the square tower that look round from a distance. This argument from illusion, has not, on the whole, impressed commentators; yet, there were some of Descartes’ contemporaries that pointed out that since contemporary errors become known from further sensory information, casting wholesale doubt on the evidence of the senses cannot be right. Nevertheless, Descartes, he regarded the argument from illusion as only the first stage in softening up process which would ‘lead the mind away from the senses.’ He admits that there are some cases of sense-based belief about which doubt would be insane -‘for example the belief that I am sitting here by the fire, wearing a winter dressing gown.’

At this point, Descartes introduces a fresh reason for doubt -the celebrated ‘dreaming argument. ‘How often, asleep at night, am I convinced of just such familiar events, that I am here in my dressing gown, sitting by the fire, when in fact I am laying undressed in bed observing that there are ‘no’ conclusive signs: In which being awake can be distinguished from being asleep, Descartes proceeds, in effect to mount a general doubt about whether we are justified in asserting the really extra-mental existence of any particular object that we appear to perceive via the senses. Critics of this argument have suggested that the very concept of dreaming is parasitic on the concept of waking life, so that, again, we have not been offered an overall reason for doubting the existence of external objects. Descartes’ defenders, however, can plausibly reply that if in any particular instance te possibility that one is dreaming cannot be ruled out, the solitary doubter has no guarantee of the independent existence of any given object of perception. The conclusion that Descartes eventually draws is that any paradigm of science makes existential assumptions (such as physics, astronomy and medicine) are potentially doubtful, and that only disciplines like arithmetic and geometry ‘which deal only with the simplest and most general things, despite whether they exist in nature or not enjoy intuitive certainty.’

Yet, even this last certainty is undermined in Descartes’ most radical argument for doubt -the deceiving God hypothesis: if, as I have been taught, there is an omnipotent being who created me, then ‘how do I know that he has not brought it about that I go wrong every time I add two and three or count the sides of a square?’ There may, of course, be no God, but then, Descartes reasons, I owe my existence not to a divine creator but to some chance chain of imperfect causes. Then, there is even less reason to suppose that my basic mathematical judgements are sound. By the end of the First Meditation, the mediator is ‘tumbling around’ in a vortex of doubt. There is ‘no one of my former beliefs about which a doubt may not properly be raised.’ Descartes dramatizes this horror of extreme uncertainty by invoking a ‘supreme powerful and malicious demon’ intent on deceiving me in any way he possibly can.

Despite the commonly employed label ‘Cartesian scepticism’ realizing that Descartes is in no sense a sceptic is important. The systematic doubt is merely a means to an end: The aim is to demolish to rebuild -to throw out the rubble and lose sand to reach a bedrock of certainty. That bedrock is reached in the Second Meditation in the famous Cogito argument: ‘Let the demon deceive me as much as he can, he will never bring it about that I am nothing while I think I am something. So, I must conclude that this proposition, I am, I exist is necessarily true whenever it is put forward by me or conceived in my mind’ as Descartes phrased it in the Discourse, ‘I am thinking therefore I exist’ (je pense donc je suis) is ‘so firm and sure that the most extravagant suppositions of the sceptics were incapable of shaking it.’ The most interesting epistemic feature of the Cogito argument is the way in which Descartes extrudes certainty from the very process of doubting: The act of casting doubt on the proposition that one is thinking confirms its truth, and this in turn unavoidably implies that there must be an existing subject. Even that in existential truth, I exist, surviving everything the sceptics throw at it.

Descartes’ questioning of his previous beliefs is not as radical as is often supposed. To reach the certainty of the Cogito, he has to rely on an unquestioned underlying conceptual apparatus -for example, his grasp of what is meant by knowledge, or by doubt, and of the principal that ‘to think one must exist’ this that the Cartesian project is not, as is something suggested, ‘the validation of reason’ apart from the fleeting suggestion in the First Meditation, that even the fundamental truths of logic and mathematics might be unstable, there is never any attempt to start with a completely blank slate. If the doubt were as extreme as that, the very process of systematic meditation could never get off the ground in the first place. What Descartes aims to show, is that there is an inescapable logical limit to scepticism about what exists: Pushing such doubt to its limits shows that it is self-defeating. Once the existence of at least one item, the thinking self, has been arrived t, Descartes will attempt systematically to reconstruct a reliable body of knowledge. Yet we come up against the most striking feature of the Cartesian system from an epistemological point of view: Its radically subjective orientation. Descartes has to reconstruct the knowledge ‘from the inside outward’ -from awareness of self to knowledge of the external world. Given the wholesale doubts he has raised about the latter, he can only reinstate it by relying on the resources of his own subjective consciousness. One such resource is the idea he finds within him of a supremely perfect being, and he reasons that this can only have been placed in his mind by a really existing perfect creator -God. Once God’s existence is established by this route, Descartes can proceed to reinstate his former belief in an external world, reasoning that, since God has given him a powerful propensity to believe that many of his ideas have their source in really external objects, such objects must exist -otherwise e the deity would be systematically deceiving him, which would be incompatible with divine perfection.

Two important points need to be made about the general Cartesian approach to conative knowledge. The first is that when Descartes’ reconstruction project has been completed, the resulting edifice is very different from the ‘commonsense,’ pre-philosophical world of the man of the senses. Physical objects exist -that much is guaranteed but, ‘they may not at all exist in the way that exactly corresponds to my sensory grasp of them -for often the grasp of the senses is obscure and confused.’ To achieve a reliable grasp of the nature of physical reality. Descartes urges that we must systematically disregard the confused deliverance of the senses, and rely instead on the ‘clear and distinct’ concepts of pure mathematics that God has implanted in our souls. Even so, the resulting structure of Cartesian sciences sets out to reduce all physics to ‘what the geometers calls quantity, and take as the object of their demonstration, i.e., that to which every kind of division shape and motion is applicable.’ The world of the senses, the quantitative world of smells and tastes and colours and sounds, is thus, resolutely excluded from Cartesian science -an exclusion that remains to this day a problem for those who wish, as Descartes did, to achieve a systematic and unified understanding of reality.

The two most widely known of Descartes' schematic ideas are those of the methods of hyperbolic doubt. Each bit of an argument that, even if he may doubt, he cannot doubt that he exists. Yet we are to realize upon the fundamental components by whose functionally dynamic attributions are for Descartes' his schematic world-view that accountably his philosophical approach may objectively refuse to accept for which of depictive reason’s find in them a continuing source from which might by its concurring and evidential agreements, as we are by some understandings as formed by some sustaining primordial philosophy -all the same, he refuses to take on the obviousness for which its common sense make known to or so by understanding of indistinguishable communication. In the search for some scrupulous structural foundations in philosophically assumptive thought, which might we conclude from evidence, that is in the finding detection for which premises of doubt, again, in construing constructions by some labouriously contained fractions, are those that ease the given rejection. In that this obviousness might lay succumbing to all resolutions toward trust, and to affix the understandable value’s qualities and bring to a clearer and more of a distinctively foreseeable affirmation as to any cancellation to consider by some measure of trust. This, of course, may be construed as of Descartes’ proportionate aesthetic values, for which in their own layers of beliefs and opinions overshadow that which is thoroughly given toward his view of truth. Composite characteristics are exceedingly hesitant, that the simple fact of doubting it, and the inescapable inference that something exists doubting, namely Descartes himself.

His next task is to reconstruct our knowledge piece by piece, such that at no stage is the possibility of doubt allowed to creep back in. In this manner, Descartes proves that he himself must have the basic characteristic of thinking, and that this thinking thing (mind) is quite distinct from his body, that the existence of God, which of the existence and the nature of the external world, and so on. What is important of this, as, of course, that for Descartes is, first, that he has shown that knowledge is genuinely possible (and thus that sceptics must be mistaken), and, second, that, more particularly, a mathematically-based scientific knowledge of approving to the material world of its studious possibilities.

A self-knowledge and self-identity are normally the way one knows something about oneself is significantly different from the way one knows the same sort of thing about anyone else. Knowledge of one’s own current mental states is ordinarily not grounded on information about behaviour and physical circumstances. Knowledge of one’s actions, and of such facts as that one is sitting or standing, is usually ‘without observation’ o r, at any rate, not based on the sorts of observations that ground one’s knowledge of the actions and posture of others. One’s perceptual knowledge of one’s situation in the world, e.g., that one is facing a tree, differs markedly from the perceptual knowledge others have of the same facts, since it usually does not involve perceiving itself. One’s memory knowledge of one’s own past is normally very different from one’s memory knowledge of the pasts of others; one remembers one’s thoughts, feelings, perceptions and actions ‘from the inside,’ in a way that does not depend on the use of any criterion of personal identity to identity a remembered self as oneself.

Although in all these cases’ one could speak of a ‘special’ first-person access, it is the excess people have to their own mental state’s hat has attracted the most attention. Some philosophers have denied that there is a fundamental difference between first-person and third-person knowledge of mental states. Others, have maintained that where the difference seems most pronounced, i.e., for pain ascriptions, the first-person’avowals’ are not really expressions of knowledge at all. So that, of the philosophy of mind, is founded on the rejection of the Cartesian idea that a person discloses the contents of his mind by identifying inner objects and describing them, hence of an intension is not based on a self-examination that parallels the investigation of the world around us, it is only marginally liable to error and is an artificial expression of the intention replacing a natural one.

Such views are manifestations of the twentieth-century reaction against Cartesian views about self-knowledge that are often associated with the claim that their ae radical first-person/third-person asymmetries. These include the views that the mind is transparent to itself, which mental states are ‘self-intimating,’ those first-person ascriptions of mental states are infallible, and that self-knowledge of mental states serves as the foundation for the rest of our empirical knowledge, least of mention, tat the view is sometimes stated about the structure of knowledge than of its justified belief. If knowledge is true justified belief, and some further condition, one may think of knowledge as exhibiting a foundationalist structure by virtue of the justified belief it involves. Such views have been undermined by the work of Freud, with its postulation of a realm of unconscious whishes, intentions, etc., by work in cognitive psychology that shows most of the ‘information processing’ in the mind to be unconscious which shows many sorts of introspective reports to be unreliable, and by philosophical criticisms of foundationalist account of knowledge. All the same, most recent theorists who reject these Cartesian claims would agree that the reasons for their rejection are not reasons for denying that there is first-person knowledge of mental states that differs importantly from third-person knowledge of the same phenomena.

One question about such knowledge is whether it is appropriately thought of as observational, i.e., as grounded in as kind of perception that could be called ‘inner sense.’ Modern defenders of the view that such knowledge is observational, e.g., D.M. Armstrong, 1968, that perceiving something to be a matter of a bing so related to it that it’s having certain properties is apt to cause the non-inferential belief, that there is something that has them. On this conception, saying it seems plausible, that one perceives mental states and events occurring in one’s own mind, in virtue of an internal mechanism by which mental states cause true beliefs about themselves, but cannot perceive those occurring in the minds of others, and that it is in this that one’s ‘special access’ to one’s mind consists.

Some who agree with such a ‘reliable internal mechanism’ view of introspective awareness would object to describing such knowledge as perceptual. In paradigm cases of perception, e.g., vision, the causal connection between the object perceived and the perceiver’s belief bout it is mediated by a state of the perceiver, a ‘sense-experience,’ which in some sense represents the object, that the subject can be aware of (in being aware of the look or feel of a thing). There may be no such intermediaries between our sensations, thoughts, beliefs, etc. and our beliefs about them, and this seem a reason for denying that our awareness of them is perceptual.

A different objection questions the idea, implicit in the perceptual model, that there is only a contingent connection between having mental states and being aware of them, just as there is only a contingent connection between there being trees and mountains and thee being perceptual awareness of them. It makes doubtful sense to suppose that there are creatures that have pain without having any capacity whatever to be aware of their pains. A consideration of the explanatory role of self-knowledge suggests that for many kinds of mental states the very capacity to have and conceive of such states involves immediate ‘first-person access’ to the existence of these states in oneself. To mention just one instance, if being a subject of beliefs and desires involves being at least minimally rational, and if rational revision of one’s belief-desire system in the light of new experiences requires some knowledge of what one’s current beliefs and desires are, then being a subject of such states requires the capacity to be aware of them. While we should reject any self-intimation thesis strong enough to rule out the possibility of a self-deception, or to deny mental states to animals and infants, it is far from obvious that the nature of mental states is distinct from their introspective accessibility in the way the observational model implies

Lichtenberg denied that Descartes had a right to say, ‘I think,’ Claiming that he was only entitled to ‘It thinks.’ Hume (1739) famously denied that when one introspects one find any item, beyond one’s individual perceptions, that could be the self or subject that ‘has’ them. Such denials have led some (including Hume) to deny that there is any such self or subject, and have led others to wonder how we can have knowledge of such a thing or refer to it with ‘I.’ Arguably, such denials lose their force if we abandon the observational model of self-knowledge; what is disturbing is the idea we do perceive ‘b y inner sense’ perceptions, thoughts, etc., but do not perceive anything that could be their subject. Of course, if perceiving something is construed merely for being so related to it as to acquire, in a reliable way, true beliefs about it, our capacity for self-knowledge involves our being able to perceive both individual mental events or stares and the self individuals who have them.

The peculiarities of self-knowledge are, nevertheless, closely tied to the peculiarities of a self-reference. If the amnesiac Joe Jones discovers that Joe Jones is the culprit, without realizing that he himself is Joe Jones, this will not be case of self-knowledge in the sense that concerns us, eve n though it is a case in which the person known about is the Knower himself. We are concerned with cases in which someone knows that he himself, or she herself, is so and so, where this is knowledge the Knowers would express by saying ‘I am so and so.’ One feature of first-person reference is that it in no way depends on the availability of individuating descriptions: One can refer to oneself with ‘me’ without knowing of any description that could be used to fix its reference. A related feature of ‘me’ is precisely where ‘I . . . .

Judgements are known in distinctively first-personal as that they have this immunity to error through misidentification. ‘I’-judgements that do not have this immunity, e.g., ‘I am bleeding,’ if implied from the blood on the floor, always have among their grounds some that do, e.g., ‘I see blood’ OR ‘There is blood near me.’ It is arguable that part of what gives first-person content to beliefs and other mental states are their relations to distinctively first-person ways of knowing, and that without such ‘special access’ there could be no first-person reference t all. Still, another important feature of ‘me’-. . . . Judgements are their intimate relation to action, the amnesiac Joe Jones will not be moved to action b learning that Joe Jones is I danger, but will be if he learns in addition that he is Joe Jones and so he himself is in danger.

A stronger and more controversial claim are that the special excess persons have to themselves enters the very identity conditions for the sort of things the persons are. Many have argued, following Locke, that memory access is pat of what determines the temporal boundaries of persons. A major determinant o the spatial boundaries of persons, i.e., o what counts as part of a person’s body, is the extent of direct voluntary control, and this is intimately tied to the special epistemic excess persons have to their own voluntary actions. A familiar Kantian idea is that unit of consciousness. Different states belonging to the same subject-in some way involve consciousness, or the possibility of consciousness, of this unity.

For the question of why there is something and not nothing, everything real and nothing unreal belongs to the domain of Being. Nevertheless, there is little useful that can be said about everything that is real, especially from within the philosopher’s study, so there can apparently be such a subject as Bering by itself. Nevertheless, the concept has a central place in philosophy from Parmenides to Heidegger. The central question of ‘why is there something and not nothing?’ prompts logical reflection on what it is for a universal to have an instance, and a long history of attempts to explain contingent existence by reference to a necessary ground. In the tradition since Plato, this ground becomes a self-sufficient, perfect, unchanging, and eternal something identified along some God or God, but whose relation with the every-day world remains unknown. By defining God as ‘something than which nothing greater can be conceived,’ God then exists in the understanding, since we understand this concept. However, if, . . . He only existed in the understanding, something greater could be conceived, for a being that exists in reality is greater than one that exists only in the understanding. However, we can conceive of something greater than that which nothing greater can be conceived, which is contradictory. Therefore, God cannot exist only in the understanding, but exists in reality. For if the answer to the question of why anything exists is that some other thing of a similar kind exists, the question merely arises again. So, the God that ends the question must exist necessarily, it must not be an entity of which the expressions as a quantity are the kinds of questions obtainably in their raise of a relief.

Modern logic gives little comfort to these speculations, and prompts suspicion that the question of why there is something ad not nothing is either ill-formed or profitless, since any intelligible answer will merely invite the same question. A central mistake in the area is to treat Being as a noun that identifies a particularly deep subject-matter. This is parallel to treating nothing as a name of a particular thing, perhaps is an object of dread or fear. The modern logical treatment of these notions by means of quantifiers and variables provides a defence against this error and others. The less abstract par of the study of being concerns the kinds of things whose existence e we have to acknowledge: Abstract entities, possibilities, numbers, and so on, and disputes over their reality from the subject of ontology.

The modern treatment of existence in the theory of ‘quantification’ is sometimes put by saying that existence is not a predicate. The idea is that he existential qualifiers are themselves an operator on a predicate, indicating that the property it expresses has instances. Existence is therefore treated as a second-order property, or property of properties. In this it is like number, for when we say that there are three things of a kind, we do not describe the things (as we would if we said there are red things of the kind), but instead attribute a property to the kind itself. The parallel with numbers is exploited by Frége in the dictum that affirmation of existence is merely denial of the number nought. A problem for the account is created by sentences like ‘This exists,’ where some particular thing is indicated. Such a sentence seems to express a contingent truth (for this might not have existed), yet no other predicate is involved. ‘This exists’ is therefore unlike ‘Tame tigers exist,’ where a property is said to have an instance, for the word ‘this’ does not locate a property, but only an individual. Possible worlds seem able to differ from each other purely in the presence or absence of individuals, and not merely in the distribution of exemplifications of properties.

Descartes proves the existence of the world, not from the testimony of our experience of this fact but from the innate idea of the ‘res extensa.’ We have a certain idea that is clear (presenting but one quality, extension), and it is distinct from the ‘res’ cognitans.’ This idea, granted the facility of God, and privy to any falseness, therefore the world exists, and its contributive principal claims to the attribute of extension or the annex of supplementary progression.

Concerning the nature of this corporeal world, Descartes distinguishes between what is presented for us through our senses (colours, odours, tastes, tactile sensations). That in which comes by means of the world is a machine, an inorganic world of plants and animals, and even mans, i.e., a dimension, figures, weight, position, motion. The first, not guaranteed by the veracity of God, do not have objective value; they are secondary qualities, modes with which the subject represents reality. The second that, according to Descartes, must originate through innate values, that are primary qualities and are guaranteed by the veracity of God, therefore they are real and objective.

The essential attribute of extension characterizes the Cartesian World (‘res’ extensa’), which is infinite. In this extension the power of God has placed force and movement, which the principal of absolute causality has determined. Not purpose (finalism), but mechanical determination (the laws governing ‘matter’ and ‘mathematical motion’), the determining succession of phenomena in the physical world of theory, is claimed by virtue in the ‘res extensa.’ By which, the world is a machine, an inorganic world of plants and animals, and even mans, our uniformity through which even bodies at rest or otherwise, are comfortably considered as they are machines governed by laws established by the continuity of their causal motions. As for us, the accessible groundwork may that to see, in what is otherwise the discontinuity that is so justified through the acquiring associations by some non-uniform motion and in opposition too such, is the continuity of justifications, under which motion may freely bring us the secret reservoir of continuatives phenomenons, that to its topic, is alike, maintained by some functional reason of truth, so in that respect has the quality of being to restrictive harmonious causalities, for which it may not have what is freely given peripherally by its most favourable differentiation.

The entire Cartesian system rests upon metaphysical dualism: ‘res cognitans’ (God and the human soul) and ‘res’ extensa’ (the corporeal world). These peculiar and yet particular realities are considerately as to think, that, in as far as liberty and activity are essential to a world-view of thought, the thinking being. The succession by which mechanical determinism and passivity are predominately of what is best for all possible worlds, especially of those that establishes them of the ‘res’ extensa.’ Metaphorical duality in both the soul and corporeal worlds are essentially a bipolar product of existent value qualities that have excluded all reciprocal action between the two substances because it is impossible. Thus there is opened the problem that rationalism later took up: the determination of the relationship between spirit and matter; between God (the infinite spirit) and the world (finite matter).

This problem presented even graver difficulties about the Cartesian idea of substance -that which exists without need of want concurs by its arranging evidence that may by chance of any other to exist. Such a definition of substance is applicable only to God, who because, he is ‘Causses’ is a substance that does not need of wanting to concur of another to exist. However, finite beings also are substances and although Descartes had added that finite beings need to align with want if there is to be of any concurring intent of the God that exists, the passage to the monistic idea of single substance appears quite open; this was to be the point of departure for Spinoza.

To this we must add the fact that Descartes considers thought not as a desire toward actions upon, but as the thinking substance (‘res cognitans’), that is, as a soul, whose essence is thought. Indirectly, this formality of uniting designated by its consistency that only when to God, had consequentially amounted by some detectable teachings of Descartes, and especially the danger of unifying the ideas between man and God is made easier, so that the inactive latency through which its danger is unquestionably its source to pantheism.

In the world of Cartesian matter, there exist no qualities, but only quantity, matter and motion, which act fatally, necessarily and mechanically. The mechanistic concept was to be inherited by Rationalism and Empiricism, which considered the world as a huge machine acting through mechanical forces, without purposes.

Cartesian Rationalism finds its application even in ethics. For Descartes, ethics is the science of the end of man, and this end must be determined by reason. Before one can accredit reasons for arriving at the knowledge of such an end, and by means of attributed sanction would mean in having been by reaching it. The philosopher and only he can have by reassuring those troubled of peace of mind, least of mention, the paradigm from which he will comply with until determining the rational morality that appears through reason alone. Provisory morality is made up of a few precepts: Live according to the politico-religious opinions and customs of the country, inference of mind moderates, and not exemplified by extreme opinions; govern yourself with constancy, without leaving undisturbed or, placed of yourself in having the quality of being distracted by opportunistic considerations. In a word, live in a way that assures you the greatest tranquillity.

Regarding definitive morality, Descartes holds to the full liberty of God, so that all depends on the divine liberty. God, if he so wished, could have created a world governed by moral principle opposed to those which hold today. Such an idea brings ethics to the brink of disaster. For which is interchangeably accorded by the similarity that in returning to its absolute majority, the principals, from which we can trace from such is to realize of the outstanding behaviour as familiarized in those of the same features as characterologically emphasized through their justification. In the absolute essence of God the interconnective activities are once, again, very well grounded in the subjective act of his will.

Granted the present order of creation, Descartes recognizes that the end of man is virtue and happiness. The actuation of this end is caused through reason -through the knowledge of God, of the soul, and of the world. It is attained through knowledge of God because God is the creator and unifier of the universe; of the soul, because the soul makes clear to us our superiority over material nature; of the physical world, because, governed by causal necessity, it teaches man the virtue of resignation and indifference in the face of the evils of life. As are evident, Cartesian morality does not greatly differ from Stoic ethics in which the wise man appeals to reason to assure himself of tranquillity and felicity.

The first possible solution lay in uniting Cartesianism with Platonism and conceiving of the two Cartesian substances (thought-substance and extended substance) as attributes deriving from a single divine substance. This was the solution of Spinoza, the strongest and most coherent of the Cartesian thinkers. He abolished the distinction between finite and infinite, and explained monistically and pantheistically the procession of the finite from the infinite. Spinoza answered the first of the unsolved questions, that of the relationship between God and creatures. Still, he maintained the second distinction and determined the relationship between soul and body by a psycho-physical law: That which is produced in thought by means of it’s very nature that from its particular premise of axiomatic determination, for which it can be properly detected in the accession of (body).

The second possible solution came from Augustinianism. Augustinianism, faced with the impossibility of deriving ideas from experience, had recourse to God, to a divine illumination in which God implants ideas in the human intellect. This supernatural intervention or influence could be extended to all finite reality in a way that fills the gap between the infinite and the finite, between spirit and matter, through the intervention of God Himself. This was the solution taken by Malebranche, according to whose creatures are the simply occasioned; a directorial intervention of God is the direct cause of all effects.

As Christian Malebranche maintains the distinction between God and the world, two forces, which were unified in Spinoza. Yet in determining the relationship between God and the world, Malebranche also has recourse to God. This was to achieve within the assemblage that the latent immanentism in Cartesian Rationalism was not revealed in the concept of substance in that their relationship between the two substances.

The third possible solution was sought in bringing Cartesian Rationalism into harmony with Aristotelian Scholasticism. As bearing for its consequent reason, wherefore to endeavouring a yield that is succumbing to fill the gap, in that which it can only subsist between what could we prove as a discerning relationship is respected between spirit and matter, least of mention, we are properly equipped within us to endorse of all sustaining properties that reserve the containing of rights toward that which is moderately the proper idea of potency, and so, that, as to flow spontaneously in accord within those pre-established propositional intuitivism are sanctioned by God. This law would also explain the relationship between the finite and the infinite. The monad of Leibniz is developed according to a pre-established harmony; its development is a passage or transition from a potential state to a state of representation.

Despite these intrinsic deficiencies and despite the opposition that Cartesianism has caused, that from its foremost appearances are both in the field of philosophy (Gassendi, Hobbes). Moreover, that of religions (both Catholic and Protestant), are we to be suspended from our participation through which Cartesianism, as in following the rapid circulatory presentations as displaced throughout European representations of ascendancy, and if, by way through which thought has succumbed of the period. It influenced all branches of culture. Catholic thinkers for example, those at noted centres like the Paris Oratory and the Benedictine abbey of Port-Royal, favoured the supereminent position it gave to God and the soul. The Jansenist polemics that Cartesianism instigated are a proof of this; scientists liked the geometric spirit of the system; philosophers and litterateurs were pleased with the clear and distinct ideas and the spirit of criticism carried out according to rational methods. The classic land of Cartesianism, naturally, is France during its golden age of literature.

Empiricism also developed along with Cartesian Rationalism, and felt its influence. Intuitive Empiricism is opposed to Rationalism as sensitive and intellective knowledge is in opposition. Nevertheless, it felt the influence of Cartesianism, first in a negative sense, in as far as Empiricism now rose to reaffirm its premises in its debates with Rationalism (Hobbes, Locke), in a positive way it was also influenced in as far as the principle of immanence in common to both Empiricism and Rationalism. In that Cartesianism, directly or indirectly, is that predominating tendency in the philosophy of this period; it prepares the way for Illusionism, and through Illusionism it reaches Immanuel Kant.

Descartes, in his work ‘Discourse on Method,’ has been given to the criticism of the education under which he had received (a criticism that is indirectly an attack on the Scholasticism of his day). He goes on to set up the new method, but, yet, according to him, it must be based within the characterized potential given to assure of some essential formalities as to prove, by its significance to follow all scientific and philosophical research. These laws are four: (1) To accept nothing as true that is not recognized by the reason as clear and distinct; (2) To analyse complex ideas by breaking them down into their simple constitutive elements, which reason can be intuitively apprehended; (3) Their resultant amount is to be reconstruction for within the beginning come the sublime simplicity of ideas and working synthetically toward the complex; (4) Show some accountable adequacy in a complete figure in work, the data to the problem, expending of steps in both methods of induction and deduction.

Better to understand these laws, we must note that for Descartes the point of departure is the ideas, clearly and distinctly known by the intellect

-the subjective impressions on the intellect. Beyond these clear and distinct ideas one cannot go, and why the ultimate principle of truth consists in the clearness of the idea. Clear and distinct intuitions of the intellect are true. For Descartes, such clear and distinct intuitions are thought representations held by themselves as they stand alone for the I-ness that they represent (‘Cogito’) and the theory of some enlarged and developing expansion.

Having arrived at this starting point (uncluttered and distinctive ideas), the intellect begins its discursive and deductive operation (represented by the second and third rules). The second law (called analysis) directs the elementary notions reunited with the clear and distinct ideas (the minor of the Scholastic syllogism). The third law (synthesis) presents them in every bit as the conclusion flows from the preface. The final law (complete enumeration) stresses that no link in the deductive chain should be omitted and that every step should be logically deduced from the starting point of distinctively clear and distinct ideas. Labouriously, our gaiting endeavours of motion, can only proport of issues established from an ancestral bipedalistic locomotion, as well, we can only travel one step to the next. Nonetheless, we will have obtainably gained representation through our own achieve, that of a set function of coordinate systems is regulated by their truths from which all will clearly be justly as distinct from one another. Because all those that is categorized as in participants might there be of them the same degree of truth enjoyed, least of mention, as of us that forfeit the directorial direction through it’s most originally formidable of ideas, and, from only which it can be explicitly clearer and distinctively purposive.

This, as we know, is the method adopted in mathematics. Descartes transferred it to philosophy to find clear and distinct concrete ideas, and of deducing from these, through reason alone, an entire system of truths that would also be real or objective. The Aristotelia-Scholastic method (and that, given to an overall inclination to classical realism) is also deductive, but it is very different from that of Descartes. Scholastic deduction is connected with objective reality because ideas are abstractions of the forms of the objects that experience presents. Thus, both the concreteness of the ideas and the concreteness of the deductions based on these ideas is justified.

In Descartes ideas do not come from experience, but the intellect finds them within itself. Descartes declares that only these ideas are valid in the field of reality. Thus the concreteness (or the objective validity) of an idea is dependent upon its own clearness and distinction.

Descartes, because of the principle already established in his method, had first to seek out a solid starting point (a clear and distinct concrete idea), and from this opens his deductive process. To arrive at this solid starting point, he begins with methodical doubt, that is, a doubt that will be the means of arriving at certitude. This differs from the systematic doubt of the Skeptics, who doubt to remain in doubt. Made accessibly available, as far as having made possible to see the doubt of all the impressions that exist within my knowing faculties, whether they are those impressions that come to me through the senses or through the intellect. I may doubt even mathematical truths, in as far as it could be that the human intelligence is under the influence of a malignant genius which takes sport in making what is objectively irrational appear to me as rational.

Doubt is thus carried to its extreme form. Nonetheless, asides this fact, doubt causes to rise in me the most luminous and indisputable certainty. Even presupposing that the entire content of my thought is false, the incontestable truth is that I think: One cannot lack confidence in doubt without thinking, and if I think, I exist: ‘Cogito ergo sum.’

It is to be observed that for Descartes the validity of ‘Cogito ergo sum’ rests in this, that the doubt presents intuitively to the mind the subject who doubts, that is, the thinking substance. In this, Cartesian doubt differs from that of St. Augustine (‘Si fallor, sum’), which embodies a truth sufficiently strong to overcome the position of Skepticism. Gainfully to employ the ‘Cogito ergo sum,’ Descartes is to presume, not only stifling or to subdue the Skeptic position, but as the supportive foundation for which its structural data format of a primary reality, the existence of the ‘res cognitans,’ is of the essence, in ways too further research, for which it has betaken.

This is the point that distinguishes the classic realistic philosophy from Cartesian and modern philosophy. With Descartes, philosophy ceases to be the science of being, and becomes the science of thought (epistemology). Whereas, at the outset, being applied to as conditioned to thought, now it is thought that conditions being. This principal, mostly realized by the philosophers immediately following Descartes, was to reach its full consciousness in Kant and modern Idealism.

The ‘Cogito’ reveals the existence of the subject, limited and imperfect because liable to doubt. Arriving at an objective and perfect reality is necessary, i.e., to prove the existence of God. Descartes uses three arguments that can be summarized thus: (1) Cogito has given me a consciousness of my own limited and imperfect being. This proves that I have not given existence to myself, for in such a case I would have given myself a perfect nature and not the one I have, which is subject to doubt. (2) I have the idea of the perfect: If I did not possess it, I could never know that I am imperfect. Within all possibilities, from where comes the emergent idea of the perfect? Not from myself, for I am imperfect, and the perfect cannot arise from the imperfect. Therefore it comes from a Perfect Being, that is, from God. (3) The very analysis of the idea of the perfect includes the existence of the perfect being, for just as the valley is included in the idea of a mountain, so also existence is included in the idea of the perfect.

Regarding the nature of God, Descartes chose for less of the same attributes as does traditional Christian theistic thought. In Descartes, however, these attributes assume a different significance and value. God, above all, is absolute substance: The only substance, properly so-called (so the way is open to the pantheism of Spinoza). An attribute that has great value for Descartes is the veracity of God.

God: the perfect being, cannot be deceived and is unable to deceive. Thus, the singularity of God serves as a guarantee for the entire series of collection as acclaimed by an intuitive certainty and its distinctiveness inhabited of such characteristic cleanliness in order, that is readily seen through the perfection of ideas. They are true because if they are not true, I, having proved the existence of God, would have to say that he is deceiving, and perhaps, less than creating a rational creature from which one who is, can be deceived even in the apprehension of clear and distinct ideas. Thus, with the proof of the existence of God, the hypothesis of a malignant genius falls of its own weight.

Regarding the origin of ideas, Descartes holds that the idea of God, all primitive notions, all logical, mathematical, moral principals, and so forth, are innate. God is the guarantee of the truth of these innate ideas. Alongside these innate ideas Descartes distinguishes two other groups of ideas (a) the adventitious, which are derived from the senses; (b) the fictitious, which are fashioned by the thinking subject out of the former. Both groups are considered of little worth by Descartes because they do not enjoy the guarantee of the divine veracity, and so are fonts of error. Only innate ideas and the rational deduction prospered from them have the value of truth. This proves the existence of the world, not from the testimony of our experience of this fact but from the innate idea of the ‘res extensa.’ We have a certain idea that is clear (presenting but one quality, extension), and it is distinct from the ‘res’ cognitans.’ This idea, granted the veracity of God, cannot be false; Therefore the world exists, and its principal attribute is extension.

Concerning the nature of this corporeal world, Descartes distinguishes between what is presented through the senses (colours, odours, tastes, tactile sensations) and that which comes by way of the intellect, i.e., dimensions, figures, weight, position, motion. The first, not guaranteed by the veracity of God, do not have objective value; they are secondary qualities, modes with which the subject represents reality. The second that, according to Descartes, must be innate ideas, are primary qualities and are guaranteed by the veracity of God; therefore, they are real and objective.

To this we must add the fact that Descartes considers ‘thought’ not as an executed function but as the thinking substance (‘res cognitans’), that is, as a soul, whose essence is thought. Forthwith, this is the identification that could only belong to God. Therefore, seeing it in this teaching of Descartes throughout the dangers of unifying the conceptual representations of man and God is easy (‘Homo Deus’) and consequently the latent danger of pantheism.

In the world of Cartesian matter, there exist no qualities, but only quantity, matter and motion, which act fatally, necessarily and mechanically. The mechanistic concept was to be inherited by Rationalism and Empiricism, which considered the world as a huge machine acting through mechanical forces, without purposes.

Regarding definitive morality, Descartes holds to the full liberty of God, so that all depends on the divine liberty. God, if he so wished, could have created a world governed by moral principals opposed to those with which we hold today. Such ideas bring ethical disaster, in that, if morality is like this would it not be found through its justification in the absolute essence of God or in the arbitrary act of his will.

Granted the present order of creation, Descartes recognizes that the end of man is virtue and happiness. The actuation of this end is caused through reason -through the knowledge of God, of the soul, and of the world. It is attained through knowledge of God because God is the creator and unifier of the universe; of the soul, because the soul makes clear to us our superiority over material nature; of the physical world, because, governed by causal necessity, it teaches man the virtue of resignation and indifference in the face of the evils of life. As evident, Cartesian morality does not greatly differ from Stoic ethics, in which the wise man appeals to reason to assure himself of tranquillity and felicity. Descartes left two questions unsolved: (i) the determination of the relationship between the infinite substance (God) and finite substance (the world), and (ii) the relationship between the spirit-substance (the soul) and the extended substance (body).

To fill the gap that he left between the infinite and finite, between spirit and matter, as it was, only three possible solutions are to be, that only once are we to have had to enjoy of something through the recourse to an earlier shape or type that in all forms that enlighten us to some philosophical deprivation. All three solutions were tried and developed by later philosophers: Spinoza, Malebranche and Leibniz, whose systems can justly be considered as developments of the rationalistic premises of Cartesian principals.

The first possible solution lay in uniting Cartesianism with Platonism and conceiving of the two Cartesian substances (thought-substance and extended substance) as attributes deriving from a single divine substance. This was the solution of Spinoza, the strongest and most coherent of the Cartesian thinkers. He abolished the distinction between finite and infinite, and explained monistically and pantheistically the procession of the finite from the infinite. Spinoza answered the first of the unsolved questions, that of the relationship between God and creatures. Nonetheless, he maintained the second distinction and determined the relationship between soul and body by a psycho-physical law: That which is produced in thought by it’s very nature finds’ determination in extension (body).

The second possible solution came from Augustinianism. Augustinianism, faced with the impossibility of deriving ideas from experience, had recourse to God, to a divine illumination in which God’s very implantation to not any but of more ideas that implicate man as having to enact in the light of a unique and comprehensible intellect. This supernatural intervention or influence could be extended to all finite reality in a way that filled the gap between the infinite and the finite, between spirit and matter, through the intervention of God Himself. This was the solution taken by Malebranche, according to whom creatures are the simple occasions; a direct intervention of God is the direct cause of all effects -Occasionalism.

As Christian Malebranche maintains the distinction between God and the world, two forces, which were unified in Spinoza. However, in determining the relationship between God and the world, Malebranche also has recourse to repose of God. By this he obtainably achieves the originality that is found, through the means of the latent constructs that seem most effectively striking for the Cartesian Rationalists. That, not to acknowledge the conceptual substances, is not to exceed in the differentiations between any two substances, from which will be found to have all of the same. The third possible solution was sought in bringing Cartesian Rationalism into some related harmonic symmetry with Aristotelian Scholasticism. Yet, to endeavour through the persuasions, least of mention, those that have possession for bringing us to a certain state of particular satisfactions, in that of some fixed relationship between spirit and matter can by way of accommodating any of the ideas from which are construed by their conceptual determinants. Their circulatory spontaneity is comparatively distributively contributive, as they over flow within the dynamics of emptiness, by that, their participating functions are accorded by laws that pre-established the penetrations curtailed through discovery, also, it might be to some effect, that their appraisals are very much as been sanctioned from God. This law would also explain the relationship between the finite and the infinite. The monad of Leibniz is developed according to a pre-established harmony; its development is a passage or transition from a potential state to a state of representation.

In the face of these intrinsic deficiencies and in spite of appositional constraints with which Cartesianism has caused, in a major way there is given to appear of both subject fields of philosophy (Gassendi, Hobbes), and the religiosity of combining formidable denominations (both Catholic and Protestant), bringing together the estranged dissimilarities by foreign legitimacies that are thoroughly categorized by enforcing priorities of culminating Cartesianism, but, it is nonetheless, that a spread of rapid emigration throughout Europe and representations in the dominant vectors of thought, so let us be pleased of the ripening season. It influenced all branches of culture. Catholic thinkers for example, those at noted centres like the Paris Oratory and the Benedictine abbey of Port-Royal, favoured the supereminent position it gave to God and the soul. The Jansenist polemics that Cartesianism instigated are a proof of this; Scientists liked the geometric spirit of the system; philosophers and litterateurs were pleased with the clear and distinct ideas and the spirit of criticism carried out according to rational methods. The classic land of Cartesianism, naturally, is France during its golden age of literature, the age of Louis XIV.

Descartes proves the existence of the world, not from the testimony of our experience of this fact but from the innate idea of the ‘res extensa.’ We have a certain idea that is clear (presenting but one quality, extension), and it is distinct from the ‘res’ cognitans.’ This idea, granted the veracity of God, cannot be false; therefore the world exists, and its principal attribute is extension.

Concerning the nature of this corporeal world, Descartes distinguishes between what is presented through our senses (colours, odours, tastes, tactile sensations) and that which comes by way of the intellect, i.e., dimensions, figures, weight, position, motion. The first, not guaranteed by the veracity of God, do not have objective value; they are secondary qualities, modes with which the subject represents reality. The second that, according to Descartes, must be innate ideas, are primary qualities and are guaranteed by the veracity of God; so they are real and objective.

The Cartesian World is characterized by the essential attribute of extension (‘res extensa’), which is infinite. In this extension the power of God has placed force and movement, which are determined by the principal of absolute causality. Not purpose (finalism), but mechanical determination (the laws governing matter and mathematical motion) governs the succession of phenomena in the physical world, in the ‘res extensa.’ The world is a machine. The inorganic world, plants and animals, and even man, to his body, are machines governed in the laws existent through the causality of motion.

The integrated priority bestowed of the Cartesian system rests upon its metaphysical dualism: ‘res cognitans’ (God and the human soul) and ‘res’ extensa’ (the corporeal world). These two realities are irreducible, in so far as thought, liberty and activity are essential to the world of the thinking being, and extension, mechanical determinism and passivity are essential to the world of the ‘res extensa.’ All reciprocal action between the two substances is excluded because it is impossible. Thus there is opened up the problem that was later to be taken up by rationalism: the determination of the relationship between spirit and matter; between God (the infinite spirit) and the world (finite matter).

Rationalism, however, is a philosophical system based on methods of inquiry grounded in reason, primarily that of mathematical deductive reasoning. Discounting sensory experience as the source of knowledge, extreme rationalists believe that all complex systems of information, such as the truths of the physical sciences and history can be derived simply by thinking about the subjects as consequences of axiomatic principle and their logical corollaries.

Rene Descartes is one best-known proponent of rationalism. He sought to outline a process of philosophical thought that was independent of the old scholastic and theological traditions of his time. Believing that all sound judgments must go on from a mathematical basis, he created of what is called ‘The Cartesian Method.’ Its four basic laws are as follows: The Cartesian Methods comprise as of: (1) Committing to nothing, would define of anyone as not to accept any propositions as true, that are not clear and distinct. (2) Break a problem down into its constituent parts and analyse it as such. (3) Structure thoughts from simple too complex as the order of study. (4) Enumerations must be complete with nothing omitted.

This systematic approach is a way that mathematics is structurally given. As, Descartes applied it to philosophy with which its intention was that it might make metaphysically inquire into the supplementary formality as distinguished through the methodological clearnesses justly as of making of analogous examples much as they can be made clearly by meaning. Making into of what might be agreeable, is that of the satisfactory behaviour -fixed and as a user of this method that is mostly famous to the Cartesian statement: ‘Cogito ergo sum‘ (I think; therefore I exist), where he formed the basis for his metaphysics. He thought that doubt was simply a different form of thought, so ‘doubting’ that one did exist was not a serious threat to validity of that principal. It was the intuitively known axiom that formed the basis for the rest of Descartes' philosophy of Rationalism.

Descartes' next work was with the concept of God, a perfect being in his belief that he sought to prove in existence of, . . . He constructed his proof in the following manner, following his own Rationalist method to do so: The Cartesian Proof of God: (A) I am subject to doubt; therefore I am ‘the perfect’ to grasp onto the imperfect; thus, I am not the cause of my existence. (B) I have the ‘idea‘ of ‘the perfect.’ This idea must come from a perfect Being. That to a greater extent and made clearly satisfactorial, its point is implied directorially furnished by the analysis of the idea does the existence of the perfect being.

As for ideas, Descartes holds that some ideas come from God; these ideas are innate. Others are derived from sensory experience, and still others are fictitious, that is; they are created by the imagination. He thinks that the only ideas from which are, in fact, valid in those that are innate. All others are subject to fallacy. Also, central to Descartes' argument was his notion of the dualism of substances. Cartesian thought has remained central to philosophy, especially during the 17th century of almost 300 years since. Its understanding of a regiment of guideline principal is most fundamental to grasping rationalism itself. Descartes left several things out of his medium-line of reasoning, in particular, his analysis of God and his lack of defining the interconnection between the sensory and rational world. Other proponents of rationalism would attempt to rectify these problems as rationalism was developed as to simplify a philosophic system after Descartes.

Another famous rationalist, Baruch Spinoza, expanded upon the basic principal of rationalism. His philosophy entered on several principal, most of which relied on his notion that God was the only absolute substance; this idea is very similar to Descartes' conception of God. Spinoza argued that God was a substance composed of two attributes: thought and extension. ‘Substance’ in Spinoza's view is something actual, eternal and perceived by the intellect. Any attributes that a substance has define its essence.

Spinoza also defined the term ‘mode‘ in his philosophy to be any variations or modification of that basic substance; essentially they are different forms of a similar thing. He believed that man and all aspects of the natural world were modes of the eternal substance of God. God can only be known through pure thought. This fact is distinctly rationalist; Spinoza thought that the only eternal substance could be known via reason alone, not sensory evidence. Through ethics, then, Spinoza believed that all moral behaviour could only be defined by the fact that we were variations on the definitions, so morality had to come through a definition of God's essence.

Gottfried Leibniz was another famous rationalist. Determined to rectify some problems that were not ratified by Descartes, he explored certain Aristotelian notions and attempted to combine Descartes' work with Aristotle's concept of form. He so believed that ideas exist in the intellect innately, however through his virtuality that established a sense that it is only when the mind reflects upon its own Beingness that it soon becomes actualized. Most of what is real of the substance, the real from Leibniz's point of view, which is the ‘monad.’ Monads are not things of extension, or have the continuance through succession and bring forth a progressive expansion, moreover, all without any supplementary delay. Every bit as their similarity is built upon the same edifice under which is to its supporting structure by which Spinoza, in addition to the many things that include of its strengthening activity, may consist of representational states that are pleasantly apperceptive in their boasting representations that peak within their existent force fields of consciousness. All activity that is represented in the monads is regulated by God, a being that is also a ‘monad.’

Rationalism relies on the idea that reality has a rational structure in that all aspects of it can be grasped through mathematical and logical principle and not simply sensory experience. Ethical and political principals are structures accorded of what is often given in agreement to the concepts of God as the absolute for moral conduct. The mind under this doctrine is not ‘a blank slate,’ thinking that these are not blank imprints seems positive, but show the evidence for providing senses of some functional details that evoke, least of mention, the principal by whom of responding to mathematical formulation and makes for methodological reason as exceptionally cognate.

It is not really as overwhelming that the philosophical/theological error that we call ‘modernism’ should begin with a dream. The dream, or actualities of self as perhaps are an arousing set of consecutive dreams, that happened on the night of November 10, 1619, the vigil of the Feast of St. Martin of Tours, under which a time of great feasting in the France of Rene Descartes' time. We are right to wonder whether Descartes ‘protests too much’, when he asserted in his autobiographical work that he had abstained from wine for some time before the night of his famous dreams. What he does admit, however, is that for several days before his experience, which would transform the basic orientation of philosophy, he had felt a ‘steady rise of temperature in his head.’

The young Descartes, some 23 years old when he found himself on that cold November night ‘shut up alone in a stove-heated room (poele),’ had been quite an eccentric in his early years. Might there be of some controversy between English-speaking commentators about their concerns that regard of whether poles show that Descartes was ‘shut up in a stove-heated room’ or that he was ‘shut up in a stove,’ or whether of possibilities that might say that, ‘Dogs bark’ is true, or whether they simply say that, dogs bark, still might they say that the truth condition of ‘snow is white’ is that snow is white, also saying that ‘Britain would have capitulated had Hitler invaded’ is that Britain would have capitulated had Hitler invaded? These disputed elementary definition of running-on-the-spot disqualifies truth conditions from playing the central role in a substantive theory of meaning. It is, that Descartes' periodic intervals of general restlessness of spirit (not surprising if he were in the habit of shutting himself up in stoves) had manifested themselves during his adolescent years when he left behind his Jesuit schooling, of which he had a decidedly mixed impression, and ‘took up the book of the world.’ Tired of what he felt to be the endless intellectual discussions and controversies that taxed and left dubious the minds of so many, he put aside the reading of books and took up the practical matter of war, which the Central Europe of the early seventeenth century had made available to him as the 30 Years War between the forces of the Habsburg Catholic Holy Roman Emperor and those of the Protestant Princes of Northern Europe. It was as a ‘fighting man’ of the army of the Duke of Bavaria (although, no historic evidence had been given by Descartes, only for which he did not assert strongly of), that he found himself on that November day, holed up in a stove-heated room, wintering with the army in the German city of Ulm.

On this day, Descartes was meditating on the ‘disunity and uncertainty’ of his knowledge. Since his days at the Jesuit lycee [i.e., high-school/college] at La Fleche, he had marvelled at mathematics, especially geometry, a science in which he found certainty, necessity, and precision. How could he find a basis for all knowledge so that it might have the same unity and certainty as mathematics? Having in mind, for several years, a project and method to bring all the sciences together within the context of new universal philosophical ‘wisdom,’ Descartes interpreted the vivid dreams that he had connected along with the night of the Vigil of the Feast of St. Martin as a sign from God Himself. From that moment on, Descartes would believe that he had a divine mandate to establish an all-encompassing science of human wisdom. He himself was so convinced of this divine endorsement of his ‘mission,’ that he would make a pilgrimage to the Holy House of Loreto in Thanksgiving for this ‘favour.’

What could be the contextual representation as regarded to some immeasurable value of dreams, in that it promotes itself of the passions that are unformidably caused by the senses. However the objectivity, that its mission has taken to be so seriously that Descartes was ready to modulate all systems of thought developed before his own, perhaps, the exclusive passion of Scholasticism, was an owing requisite for his ‘pre-Philosophic.’

As for these dreams, it is the third that best expresses the original thought and intention of Rene Descartes' rationalism. During the dream that William Temple aptly calls, ‘the most disastrous moment in the history of Europe,’ Descartes saw before him two books. One was a dictionary, which appeared to him to be of little interest and use. The other was a compendium of poetry entitled Corpus Poetarum in which may have the quality of being a union of philosophy in the accompaniment of wisdom. Moreover, the way in which Descartes interpreted this dream set the stage for the rest of his life-long philosophical endeavours. For Descartes, the dictionary stood merely for the sciences gathered in their sterile and dry disconnection; the collection of poems marked more particularly and expressly the union of philosophy with wisdom. He shows that one should not be astonished that poets abound in utterances more weighty, and even more fulling is their meaning and fully expressed, than those found in the writings of philosophers. In each phraseological oddity enough there comes to the conclusion from of a man who would go down in history as the father of Rationalism. As justified by Descartes’ associates he comes through as the ‘marvel’ of wisdom, and to this, is with poets whose divine nature into which their inspiration and that dare have its phantasy. Only from which they’ll ‘strike out’ the seeds of enlightenment, they’re, is existing in the minds of all men like the sparking flames of awareness. By that of burning from the embers that once their glow gave into aflame, the fires of consciousness and their striking effortlessly indirect. Under which the more complacent came for itself, giving reason to posit for itself within the ease of philosophy. The written inscriptions by some professional philosophers of his time, have charged Descartes for failing to extend the assuring certainty for which the human urgency, and charismatic presentation with which we associate with the manifestations as capably organizing our knowledge and influencing our behavioural conduct.

It would be an unfortunate intellectual and historical mistake to take Rene Descartes for a relativist, who wished to undermine all certainty, along with dividing the individual sciences from each other into airtight compartments. That the contemporary result of Cartesian Rationalism has been nothing but relativism and the fragmentation of knowledge is, simply, the ironic outcome of Descartes' efforts toward the attainment of certainty and ‘universal mathematics.’ Here we must remember the traditional Aristotelian/Thomistic understanding that each specific science, e.g., botany and entomology had not only its own proper object of study (e.g., plants or insects), but, also, its own proper method of investigation and demonstration. This is why Descartes' insistence upon a single ‘universal’ method, resembling the method employed in geometry, are so destructive and disorienting. As we will be shown the clear and explicative comprehension for which the method that Descartes constructs to achieve scientific certainty, it was his departure from agreed upon philosophical principle and fundamental presuppositions that causes the philosophical trend he initiates to steer the post-Christian mind into the ditch of democratic relativism and religious indifferentism.

To clear an operated misconception about the thought of Rene Descartes will be needed to emphasize that although Mathematics, particularly the mathematical science of Geometry. They’re being for which collocated with to provisions for Descartes the general structure and procedure of his intellectual method, it must be remembered that Descartes did not at all view Mathematics as the highest and most intellectually efficacious science. Borrowed from the Mathematical ‘methods,’ which he defines as ‘reliable rules,’ that are easy to apply, and such that if one follows them exactly, one will never take what is false to be true or fruitlessly expend one's mental efforts, but will gradually and constantly invariant changes of the increasing abilities for ones knowledge (scientia) till one arrives at a true understanding within one's capacity. What disturbed Descartes about his own intellectual milieu was that men of learning were becoming specialists to the extent that they were forgetting achieving the state of ‘wisdom,’ which had traditionally been the objective of both philosopher and sage.

The image that Descartes used to portray his understanding of the new rationalist scientific ‘wisdom,’ was a tree, the ‘tree of wisdom.’ Every tree has three appearances, roots from which the tree is fixed to the ground and from which it gains its nourishment. The trunk of the tree that is the main quantitative mass of the tree and upholds the branches, and, finally, the branches that produce the flower or the fruit that both perpetuate the tree’s existence and expresses of the highest productive capabilities, and analogously from the tree, so to with the tree of philosophical and scientific knowledge. Descartes identifies the roots of the tree with metaphysics, especially the three most fundamental metaphysical concepts of God, the human thinking self, and the external material world. These three ideas, we can see the inevitable movement of Rationalism and all the philosophical schools related to it. The most fundamental realities in existence are spoken of and philosophically treated as ideas rather than things, provide the intellectual justification for the ‘trunk’ of the tree, a philosophically grounded physics that would give an account of all motions of quantitative being. The three branches, which Descartes speaks of, are the practical sciences of ethics, mechanics, and medicine. These three were the sciences, which Descartes felt had to be necessarily grounded in metaphysical knowledge, which would allow people to attain the goal that Descartes stated to be the primary goal of his new scientific method, making humanity the ‘master of nature.’

It is for us to see that, from the perspective of the perennial philosophical tradition, Descartes has inverted the very orientation of pedagogy and scientific speculation. In a very real way, Descartes' tree is ‘upside down.’ The practical arts and sciences should serve as the practical ‘ground’ (i.e., in the sense of providing for the necessary ordering of the physical and social realm of man) for the ultimate act of human intelligence that of intellectual contemplation of nature, the human soul, and most especially God. In Descartes' ‘Tree of Wisdom,’ the newly characterized ‘ideas’ of God, the human ‘self,’ and the external material world, are only the intellectually efficacious principles, which allow for the deduction of an entire system of truths derived from an analysis of the conceptual necessities inherent in the ‘ideas’ of God, the human thinking self, and the external material world themselves. In other words, what ought to be the highest object of intellectual contemplation -the goal and fruit of all scientific speculations become no more than a necessary intellectual step in a logical method that has as its intent the subjection of nature to the natural wishes and desires of man. It is interesting that Descartes had as one of his greatest hopes for his new rationalist science, the indefinite extension of a human longevity. That Descartes himself should have died at the young age of 54, after a short spell of cold weather in Stockholm, Sweden in 1650, foreshadowed the sterility of rationalist ‘first principles’ both in the speculative and in the practical domains.

What is prototypically necessitated, is how a system can be consenting by referring to by name ‘rationalism’ and, yet, appear prima facies to be so counterintuitive and irrational. Descartes' honest hope to derive all scientific knowledge concerning the structure and motions of the universe in a deductive way from three ‘self-evident’ ideas by simply analysing the conceptual necessities inherent in those ideas appears not only supremely irrational, but also downright fanciful. It is not surprising that the young scientist Huygens, who was both a physicist and an astronomer, along with being a contemporary of Descartes, saw nothing more in Descartes' great ‘scientific’ work Principes de la philosophe, than an extraordinarily interesting novel. What is even more irrational and counter-intuitive, which Descartes understood thoroughly as a necessity by which its deriving continence to this literal ‘universe?’ Scientific knowledge as based from the idea that Descartes had in himself these existing qualities as to assign a characteristic attribute or the condition from which some processes may have availabilities, least of mention, that individually purposive, must we then have our way of being to think. In every way, it is entirely guised for a thinking being, that may have its ways for any-one particular science, especially of ones own mind and by determining that the mind itself is, by conceiving its own ideas is likely clearer and distinctly certain to falsity and for what is true. Bringing into a different state by some sorted justification, for which are those of the Rationalists of the 17th and 18th centuries, upheld in teaching about humanly civilized intellectual autonomies. In that continues of both the absolute and that without the insignificant basis in any normal human experience. Moreover, one significant consequence of such a view of human knowledge was the rejection of all appeals to authority, both philosophical and dogmatic, in establishing intellectual certainty. Another part of the fall out of the Rationalist attack on the Thomistic synthesis of theological and philosophical learning, was the relegation of Theology, since it could not be derived from the idea of the thinking self, to the realm of ‘catechism,’ which was upheld solely based on faith. Thus, Cartesian Rationalism would relegate the believing man to a position of fideisms (i.e., an act of blind faith, unsupported or unsupportable by rational proof or argument).

Descartes’s theory of knowledge starts with the quest for certainty, for an indubitable starting-point or foundation on the basis alone of which progress is possible, however, the uses of hyperbolic doubt, or Cartesian doubt of investigating the extent of knowledge and its basis in reason or experience used by Descartes in the first two Meditations. It attempts to put knowledge upon a secure foundation by first inviting us to suspend judgement on any proposition whose truth can be doubted, as a bare possibility. The standards of acceptance are gradually raised as we are asked to doubt the deliverance of memory, the senses, and even reason, all of which can let us down. The process is eventually dramatized in the figure of the evil demon, or ‘malin génie,’ whose aim is to deceive us, so that it senses, memories and reasoning lead us astray. Making a request for then becomes one of finding some demon-proof points of certainty, and Descartes produces this in the famous ‘Cogito ergo sum,’ T think, therefore I am. It is on this slender basis that the correct use of our faculties has to be re-established, but apparently Descartes has denied himself any materials to use in reconstructing the edifice of knowledge. He has a basis, but no way of building on it without invoking principles that will not be demon-proof, and so will not meet the standards that has apparently set himself. Interpreting him as using is possible ‘clear and distinct ideas’ to prove the existence of God, whose benevolence e then justifies our use of clear and distinct ideas, e.g., ‘God is no deceiver,’ this is the notorious ‘Cartesian circle.’ Descartes’s own attitude to this problem is not quite, at times he seems more concerned with providing a stable body of knowledge that our natural faculties will endorse, than one that meets the more severe standards with which he starts. For example, in the second set of ‘Replies’ he shrugs off the possibility of ‘absolute falsity’ of our natural system of belief, in favour of our right to retain ‘any conviction so firm that it is quite incapable of being destroyed.’ The need to add such natural belief to anything certified by reason is eventually the cornerstone of Hume’s philosophy, in the basis of most 20th-century reactions to the method of doubt.

By locating the point of certainty in my own awareness of my own self, Descartes gives a first-person twist to the theory of knowledge that dominated the following centuries in spite of various counter-attacks speaking for social and public starting-points. The metaphysicians associated with this priority are the famous Cartesian dualism, or separation of mind and matter have two different but interacting substances. Descartes rigorously and rightly sees that it takes divine dispensation to certify any relationship between the two realms’ thus divided, nd to prove te reliability of the senses invokes a ‘clear and distinct perception’ of highly dubious proofs of the existence of a benevolent deity. Thus, has not net general acceptance: as Hume drily puts it, ‘to have recourse to the veracity of the supreme Being, to prove the veracity of our senses, is surely making a very unexpected circuit.’

In his own time Descartes’s conception of the entirely separate substance of the mind was recognized to cause insoluble problems of the nature of the caudal connection between the two. Although the theory of Occasionalism has never been widely popular, and in its application to the mind-body problem many philosophers would say that it was the result of misconceived Cartesian dualism. It also causes the problem, insoluble in its own terms, of ‘other minds.’ Descartes’s notorious denial that non-human animals are conscious is stark illustration of the problem. In his conception of matter, Descartes also gives preference to rational cogitation over anything derived from the senses. Since we can conceive chainages to its sensible qualities, matter is not an empirical concept, but eventually an entirely geometrical one, with extensions and motion as its only physical nature.

It is, nonetheless, adeptly derived of these foundational ‘first notions’ (i.e., of God, the thinking self, and the external material world) from which all the rest of human knowledge and science would be derived in an deductively fashion (i.e., before and exclusive of any sensible experience of the external natural world), the mind, according the Cartesian Method, needed to engage in two distinct processes. The first was analysis and the second was synthesis. Analysis involved ‘dividing up each difficulty that I was to examine into as many parts as possible and as seemed requisite. Descartes was convinced that he had followed this way of analysis (really, what should be called reductionism), in his most influential book, The Meditations on First Philosophy, by resolving the bounteous data of human knowledge and experience into the primary existential proposition, Cogito, ergo sum, i.e., I think, therefore, I am.

According to Descartes, all mental content could be reduced to three ‘innate’ (i.e., meaning ‘in born,’ that is, not gained by experience of the external world known through the senses) ideas, the idea that I have of myself, the idea I have of God, and the idea I have of materiality. These ideas were to be grasped with an absolute and certain intuition. By ‘intuition,’ Descartes meant a purely intellectual activity, and intellectual ‘seeing’ or ‘vision,’ which is so clear and distinct that it leaves no room for doubt. In another definition of intuition, Descartes said, ‘Intuition is the conception, without doubt, of an unclouded and attentive mind, which springs from rational analysis alone.’ It was from these primary and ‘irreducible’ ideas, which Cartesian Rationalism believed it could derive, through the intellectual process of deduction, all the content of human science and wisdom. That such an theoretical (i.e., that which is gained before and independent of concrete, sensible experience of the material world) conception of human science could ever pass itself off as ‘rationalism,’ is one of many ironies presented in the history of philosophy. Surely such counterintuitive gibber can only be explained by the Cartesian desire to establish the mind’s reasoning processes about which the foundation of the mind itself, rather than on a rational and lived encounter with a material created order that the mind necessarily recognizes to exist independently of the thinking ‘self.’

Several years have now since passed, when I realized how numerously faithless opinions that in my youth I had taken to be lawfully-begotten, and in such a way how doubtfully attributed were the subsequent constructs caused to be joined into a mass upon them. Thus I realized that once in my life I had to raze everything and begin again from the original foundations, if I wanted to establish anything firm and lasting in the sciences, in that providing those who follow this revolution are casually the entire orientation and objective philosophical study. As we have but to see Descartes' proposed intention toward becoming empty, in that which the edifice of his previously held opinions might be build upon those discredited misunderstands, as if by some new structural foundation that supports the possibility of some positional condition, least of mention, be that for out-of-the-ordinary is a contest that in every doubt there has been spoken by the Skeptics, under which it could possibly be among the misguided. It is the key to understanding Descartes, however, that we realize that he commenced his method to eliminate doubt by appealing to doubt. This Cartesian technique of employing doubt to achieve an overcoming of doubt and a putative certainty can be called a methodological doubt (i.e., it is a doubt employed so that all doubt can be overcome). The most important thing to notice here is that Descartes begins his philosophical reflection with doubt, rather than the wonder at the order of material creation that characterizes Aristotelian/Thomistic philosophy. Since Descartes realized that he could not analyse, in any reasonable amount of time, all of his opinions that he had newfound doubts about, he writes that: Nor therefore need I survey each opinion individually, a task that would be never-ending. Because of countervailing circumstances, the substructure of functional causation, in what of anytime can put up a reinforced edifice upon it, yet to crumble of its own accordance, so, then, I will attack of those principles that supported everything as I had once to believe.

What the death-defying crafts of Cartesian Doubt and Rationalism hits were the twin towers, of the Aristotelian philosophical system, (1) our trust that the ideas in our minds are simply perfect reflections of the perceived object in the natural world and (2) the understanding that the five senses give us a real and exact knowledge of the natures of things in the material world. These two attacks were definitely part of a philosophical jihad on Aristotle and his explanation of nature and the human mind and person, however, to forget this overarching anti-Aristotelian aim, would be to overlook the essence. In this regard, we must say that Descartes himself was more anti-Aristotelian than anti-Thomistic, since he admitted, near the end of his life, that he had never read St. Thomas' Summa Theologiae and, even, regretted the fact. What he knew about St. Thomas was, therefore, received second hand from his scholastic manuals and his Jesuit teachers.

Descartes tells us that it is the information supplied to us by sensation that is the primary object of attack in his attempt to ‘strike at the foundations’ of his former opinions. It was his ‘uncertainty’ about the reliability of the data of sensation and of the images in the imagination, which have their origin in the sensible species coming from sensation, that provoked him to state the following: ‘Surely whatever I had admitted until now as most true I received either from the senses or through the senses. However, I have noticed that the senses are sometimes deceptive. It is a mark of prudence never to place our complete trust in those who have deceived us even once.’ Following adhesive yet congestive conditions from which we are to conclude, if, in at all, to any drawn conclusions upon the observation made at the beginning of this essay, in that, we must, as much of Descartes' philosophical analysis correlated upon any relation by which Descartes himself, assails to the phenomenon of dreaming. At the end of the Meditation, Descartes states that it was the continual misjudgment that the mind warranty made throughout the relational and otherwise distribution of dynamic functional states that were of the dreams. Most undermining of his trust became the shape of future events, in that his sensible experience of the world and the surrounding surfaces about him. In Meditation one, Descartes states that his normal trust in the veracity of his mental experience of the sensible world was all ‘all right’ was I not a man who is accustomed to sleeping at night, and to experiencing in my dreams the very same things, or now and then even fewer plausible ones, as these insane people do when they are awake.

By inserting this slight doubt concerning the veracity of his sensible and imaginative experience, Descartes moved to the next stage of his method that was to state that, should I withhold my assent no less from an opinion that is not completely certain and unconditionally would I of those be patently false. Consequently, it will suffice for the rejection of all these opinions, if I find in each some reason for doubt. It would, therefore, for the sake of a procedural method supposed to yield only certain and specified knowledge. Descartes is going to reject as deceptive and distortive all his ideas that have their origin in sensation.

Descartes' mathematicians had against the probable will even turn themselves upon the science of mathematics, when, in his attempt to radicalize his methodological doubt, Descartes will postulate the idea of an evil genius. This ‘evil genius’ is used as a conceptual device to undermine our trust in the certainty of our judgments concerning mathematical truths. That 4+4=8 seems perfectly evident, with no serious reason for doubt. However, what if a being had created me who wanted to deceive me and he made me so that everything that I take to be absolutely certain is false. With this idea of a creative ‘evil genius,’ Descartes clears the mental field of all certain that could upstage his autonomous thinking self.

It is in Meditation two, where Descartes initiates the long-lasting trend, which we could name ‘philosophical modernism’ or ‘subjectivism,’ which bears its bitter fruit in the New Theology of the 20th century. It is here where we see the fatal ‘movement toward the thinking self,’ under which characterizes most of the philosophical movements endured of the last 350 years. It is, no doubt, fitting that Descartes use this counterintuitive idea of the ‘evil creative genius’, finally to achieve his one absolute certain truth, the truth that his own thinking mind exists, precisely just when he is thinking the idea ‘I exist.’ Descartes, is referring to the methodological device of the ‘evil genius’ states, ‘there is some deceiver or other who is supremely powerful and overshading shrewdness by whom in which are always deliberating deceive against me. Then there is no doubt that I exist, if he is deceiving me. Let him do his best at deception, he will never bring it about that I am nothing while I will think that I am something’. Descartes must exist, since even if there was such a thing as an ‘evil genius’ who is perpetually deceiving him, still he must exist to be deceived. The very fact of his possible complete deception is proof for the certain existence of the thinking self. Descartes has found his first certainty; he has established a new foundation for philosophy. For all those who follow in his wake, philosophy will have as its grounding human consciousness, and it will have as its subject matter the ideas present in the human mind.

Descartes, however, whatever the ultimate philosophical consequences of his ideas, did not want to fall into a position of solipsism (i.e., the philosophical position that states that the only things which one can know are the ideas in one's own mind). Yet to avoid this imprisoning subjectivism, Descartes needed to establish that there existed a being that had its existence independently of Descartes' own thinking self. He, also, needed to discover an ‘idea’ not subject to doubt, which would be conceptually rich enough to yield an entire physics of the material world. Descartes knew that the idea that he had of himself was as dominantly characterized by virtue of the enacting toward his thinking and willing of himself yet, was not enough. The only reality that could fit the bill was God Himself, and infinite, perfect, and all-powerful Being. However, an existent God for which is merely an idea, would not yield such results. Descartes', however, began an undertaking of Meditation three, given to turn, he was to provide some explanation as to the factual analysis that Descartes has had to an idea of God in his mind. In that, his God was truly existent and justifiably infinite, perfect, and the all-powerful Being. Even though, in doing this, Descartes uses a doubtless old argument called the ‘ontological argument.’ Nonetheless, it is the use of such an argument for resolving such profound and effectual charges against the modernity that philosophy and theology’s identified position for which their interconnection is or belongs to the idea of God.

Descartes' proof for the real existence of God, being restricted by his method to analysing his own ideas and not the created natural world around him, is that since he had an idea of a God who was an infinite and perfect being, that God must truly exist, since he, as a limited and imperfect thinking self, could not be the origin of the idea of an unlimited and perfect being. If there is to be an existent God, he would perhaps, be one who endures the unlimited and oversees our expansive universe as perfectly impervious, must he have inscribed all reasons, for that Descartes’ conditional state of mind, has taken to be his idea from which he becomes the activator of himself. Therefore, God must truly exist and he must exist independently of Descartes' thinking self.

Having secured the real existence of God, Descartes uses the perfection of God to deduce of his veracity (i.e., God does not lie). If it is against God's nature to be a deceitful evil genius, then I can imply that what I, His creature, perceives as ‘clear and distinct’ with my mind or what is told me by God-given ‘common sense’ (what Descartes calls the ‘teachings of nature’) from which it becomes the true and intuitively certain. One thing taught me by my ‘common sense’ is that the ideas that I have of the material world come to me from outside me. Since the Creator God is not a deceiver, we can imply that such a material world, independent of the thinking self, truly exists.

When at the end of Meditation (6), the last of the meditations, Descartes says, ‘Therefore I should no longer fear that those things that are daily shown me by the senses are false. On the contrary, the hyperbolic doubts of the last few days ought to be rejected as ludicrous,’ one is lead to believe that the created and uncreated orders, as they stood before the employment of the rationalist doubt, have now been reinforced as they were with the added note of ‘mathematical’ certainty. This initial impression is deceptive, however. Coming out from the employment of a universal and radical doubt, the basic realities, of God, man, and the natural material world have been transformed. Man has become a thinking thing. A thing that is philosophically and epistemologically restricted to analysis finds of itself its own ideas, in that the encompassing moderation related by its consciousness will seem as to over flow in the consumers shopping mall.

The material, and perhaps, all physical theoretic correlations are taken to be an existence along the guide lines of something as already confronting us, how more real are the subjective matters and the opposing physical theories that are measures throughout the world that emerges from this doubt. Ours’ being the one under which Aristotle and St. Thomas gave in the spoken exchange, a world-view of quality values and essences from which we are the same in our motions and potential movement’s of persuasion. That the ‘cradle’ of every Being whereby it may prove of an indirect displacement for which in those might show of its complementarities, in why reasons that justify the intermittent intervals through which time will escape by unseen suspensions that radiate its remittance. The ending of all things can in this way be as one might say, that God Himself, as Descartes explicates too further explain that upon such a rational application, and by it’s very orientation that he centres of all applicable origins, that it seems almost immediate that he adjoins of a nucleated position, and can stand openly acquainted, perhaps, as toward a better understanding of what it should be, as he built upon an edifice of supporting fundamental and yet structural foundations that by exaggerated assertions that is visualizability, viewed through those of which are universally secured by supportive constructions that can only generate its orbited centre. This, of course, is in opposition from being orbital. The red rose has become, not to mention, as a thing to be marvelled at, but also a thing to be measured. Their illuminated aspects of some measurable nature are in those that must be taken seriously by modern science and education. Only from which we are merely those that can emphasize far and beyond of what nature can be measured by quantification and depreciative measure. The ghost of human consciousness floats from mall to machine.

It is the reality of God, however, which suffers the most abuse from Descartes' rationalist method, though it seems as if no one in the history of philosophy has ‘used’ God more extensively than does Descartes. Now, however, God is reduced to a ‘fruitful’ idea that helps Descartes achieve the practical scientific results that he is much in need for those who really are in want. When Nietzsche says that, echoing Hegel, that ‘God is dead,’ for which he is simply stating that the ‘idea’ of God, has slipped out, for good, of the consciousness of European Man. Justly as for caused latency, if in fact, that proves of being to exist of some non-committed presents, in other words, of his acknowledged death only causes of God’s owing recognition. The God known by the plenitude of his creation, always studiously avoided by Descartes' deductively mind, is thus banished and, therefore, hidden from the inquiring man’s reflective eye.

When considering the fallout from the Rationalist ‘razing’ of Scholastic philosophy in so much of the Christian World, more most be considered than merely the obvious subjectivism and encroaching relativism seen for the past 350 years. It was the point in which Descartes agreed with the Skeptics of his time, their rejection of the reliability of sensation as a foundation for understanding, which should concern us most and show the path of restoration ahead. Now, in the contemporary process of education, the young are being presented with mathematical reconstructions of the world around them. Having been reduced to its quantitative aspects, at least for the ‘hard sciences,’ the world of common human experience is ignored while reconstructed ‘models’ of reality are presented to the young mind. Since God, the real God and not the ‘idea’ of God of course, did not make man to interact, both physically and psychologically, with Cartesian models of things, there will necessarily be, and we might even say that it is a healthy sign of nature ‘revoking’ a lack of interest in such mathematical and scientific models by most students, and a mere mechanical, ‘problem solving’ habit for those who are ‘interested.’ Nothing resonates; nothing follows the grain of the created human embodied psyche. Is it surprising then that much of the ‘work’ which is done in the mathematically oriented disciplines has no long lasting impact on the emerging self-understanding of contemporary youth? To build bombs, it is useful; to build boys it is not.

To strike at Modernism, we must plunge into the very heart of the matter. If man is to gain both his theological, philosophical, political, and psychological balance, he must recover that hardy realm that Descartes banished. To take seriously, St. Thomas' teaching that all knowledge begins with sensation, that all our knowledge concerning the existence of real things depends first on our seeing, touching, tasting, smelling, and feeling them, such would be the beginning of a return to sanity. For the great Thomistic tradition, the soft, bitter, pungent, melodious aspects of the natural world give us both a knowledge of the existence and the nature of things, along with stepping-stones from creatures to Creator. Let the myriads of Cartesian Men have their ‘mastery of nature.’ For us, loving the gas station that stands on the spot where the yet once grew is hard.

It has been well said that ‘all the thoughts of men, from the beginning of the world until now, are linked together into one great chain’; yet the conception of the intellectual filiation of people expressed in these words may, perhaps, be more fitting metaphor. The thoughts of men are comparable to the leaves, flowers, and fruit upon the innumerable branches of a few great stems, fed by commingled and hidden roots. These stems bear the names of the half-a-dozen men, endowed with intellects of heroic force and clearness, to whom we are led, at whatever point of the world of thought the attempt to trace its history commences, just as following upon the small twigs of a tree to the branchlets that bear them, and tracing the branchlets to their supporting branches, bring us, eventually, to the bole.

It seems to me that the thinker who, more than any other, stands in the relation of such a stem toward the philosophy and the science of modernity, I mean, that if you lay hold of any chorological sequence from which in modern ways of thinking, either in the region of philosophy, or in that of science, you find the spirit of that thought, if not its form, to have been present in the mind of the great Frenchman.

There are some men who are counted great because they represent the actuality of their own age, and mirror it as it is. Such an one was Voltaire, of whom it was epigrammatically said, ‘he expressed everybody's thoughts better than anybody.’ Nevertheless, there are other men who attain greatness because they embody the potentiality of their own day, and magically reflect the future. They express the thoughts that will be everybody's two or three centuries after them. Such an one was Descartes. Born in 1596, nearly three hundred years ago, of a noble family in Touraine, Réné Descartes grew up into a sickly and diminutive child, whose keen wit soon gained him that title of ‘the Philosopher, which, in the mouths of his noble blood relations, was more than half a reproach.

In whatever way that is to learn, by its intricate and evolving transactions are the moments whereby the temporary encompassment of consciousness and especially the strong forces of latency, where all things that have pasted are supported by the accumulating of thought, that we are to learn of its surface values, by that we have given to the derivatives in shape and types that are things of the foreseeable nurturing of natures conscious endeavours, that in all, we are to belong, when of a moment has released us upwards and as afar above for us to oversee upon the endless encircling circumference, as we are the endless circle with no end nor belong within to start a beginning as there is a given pease to the end. However, of all things that walk, breath and have their lives in Being, if be to contradiction it seems as enviably given comfort in the hope of what has of hope is that hope is hope for the wrong thing. If only to serve within some purposive allowance, as, perhaps, the dawning of something new is to some created promise by the coming of a world-view that, least of mention, might this that we are to walk upon the corpses of times generations for it is only to attest of what must be truth or a trued eventuality. Only of what is right, which is found by some kindred imagination, whereas, for the moment we draw from the summations that have travelled through space and time, that we are in belonging of our duty to man. All who are unable to satisfy their mental hunger must within the east wind of authority, be allowed in those of us who are immoderately in this position. So it is final, that the circle is now closed, and equations to eternity have all been resolved, and lastly, as it must be so, that the Universe is now complete.

It is one of Descartes' great claims to our reverence as a spiritual ancestor, who, at three-and-twenty, he saw clearly that this was his duty, and acted up to his conviction. At two-and-thirty, in fact, finding all other occupations incompatible with the search after the knowledge that leads to action, and being possessed of a modest achievement, he withdrew into Holland; where he spent nine years in learning and thinking, in such retirement that only one or two trusted friends knew of his whereabouts.

In 1637 the first-fruits of these long meditations were given to the world in the famous ‘Discourse touching the Method of using Reason rightly and of seeking Scientific Truth,’ which, at once an autobiography and a philosophy, clothes the deepest thought in language of exquisite harmony, simplicity, and clearness.

The central propositions of the whole ‘Discourse’ are these. There is a path that leads to truth so surely, that anyone who will reason, if entirely possible it must need to reach the goal, or grasp to its thought to the opinions reached, because, it must be to whether his capacities are great or small. There is one guiding rule by which a man may always find this path, and keep himself from straying when he has found it. This golden domineer is -permit no propositions but those that the truth is clear and distinct, in that they cannot be doubted.

The enunciation of this great first commandment of science consecrated Doubt. It removed Doubt from the seat of penance among the serious sins to which it had long been condemned, and enthroned it in that high place among the primary duties, which is assigned to it by the scientific conscience of these latter days. Descartes was the first among the moderns to obey this commandment deliberately. As a matter of religious duty, to strip off all his beliefs and reduce himself to a state of intellectual nakedness, until he could satisfy himself as fit to be issuing. He thought a bare skin healthier than the most respectable and well-cut clothing of what might, possibly, is mere shoddy.

When I say that Descartes consecrated doubt, you must remember that it was that sort of doubt that Goethe has called ‘the active scepticism,’ whose whole aim is to conquer itself. Not that other sort born of flippancy and ignorance, whose aim is only to perpetuate itself, as an excuse for idleness and indifference. Nevertheless, defining what is meant by scientific doubt better than in Descartes’ own words is impossible. After describing the gradual progress of his negative criticism, he tells us: For all that, I did not imitate the sceptics, who doubt only for doubting involvement, and pretend to be always undecided; on the contrary, my whole intention was to arrive at a certainty, and to dig away the drift and the sand until I reached the rock or the clay beneath. Further, since no man of common sense when he pulls down his house for rebuilding it, fails to give himself some shelter while the work is in successively proceeding. Further; so, before demolishing the spacious, if not spaciously mansions in his old beliefs, Descartes thought it wise to equip himself with what he calls ‘une morale par provision,’ this may resolve to govern his practical life until he could be better prepared. The laws of this provisional self-government are embodied in four maxims, of which one binds the philosopher to submit himself to the laws and religion through which he has brought up yet another, and to facilitate the function operatively, of which once he calls for an action, as, perhaps, might he promptly and according to the best of judgments, that he abides without repining, by that result, the third rule is to seek happiness in limiting his desires, of actions that seem of their attempting satisfactions, might he be, while the last is to make the search after truth as a business of his life.

Thus prepared to go on living while he doubted, Descartes continued to face his doubts like a man. One thing was clear to him, he would not lie to himself–would, under no penalties, say, ‘I am sure’ of that of which he was not sure; nonetheless its possibilities would go on digging and delving until he came to the solid adamant or, at worst, made sure there was no adamant. As the record of his progress tells us, he was obliged to confess that life is full of delusion, that authority may be in the wrong, in that its testimony may be false or mistaken, also for what reason lands us in endless fallacies, that our very immediate memories are as often less trustworthy as hope; that the evidence of the very senses may be misunderstood; that dreams are real as long since that they last, and that what we call reality may be a long and restless dream. Nay, it is conceivable that some powerful and malicious being may find his pleasure in deluding us, and in making us believe the thing that is not, every moment of our lives. What, then, are certain? What even, if such a being exists, is beyond the reach of his powers of delusion? Why, the fact that the thought, the present consciousness, exists. Our thoughts may be delusive, but they cannot be fictitious. As thoughts, they are real and existent, and the cleverest deceiver cannot make them otherwise.

Thus, thought is existence. More than that, so far as we are concerned, existence is thought, all our conceptions of existence being some kind or other of thought. Do not for a moment suppose that these are mere paradoxes or subtleties. A little reflection upon the commonest facts is irrefragable truth. For example, I take up a marble, and I find it to be a red, round, hard, single body. We call the redness, the roundness, the hardness, and the singleness, ‘qualities’ of the marble. It sounds, at first, that the highest sculpting form of absurdity might be to say that all these qualities are modes of our own consciousness, which cannot even be conceived to exist in the marble. Yet consider the redness, with which to begin. How does the sensation of redness arise? The waves of intuitive certainty, may it attenuated matter, the particles of which are vibrating with vast rapidity, but with very different velocities, strike upon the marble, and those that vibrate with a particular velocity are thrown off from its surface in all directions. The optical apparatus of the eye gathers some of these together, and gives them such a course that they impinge upon the surface of the retina, which is a singularly delicate apparatus connected with the end of the fibres of the optic nerve. The impulses of the attenuated matter, or ether, affect this apparatus and the fibres of the optic nerve in a certain way; and the change in the fibres of the optic nerve produces yet other changes in the brain; and these, in some fashion unknown to us, lead to the feeling, or consciousness of redness. If the marble could remain unchanged, and either the rate of vibration of the ether, or the nature of the retina, could be altered, the marble seems not red, but some other colour. There are many people who are what is called colour-blind, being unable to distinguish one colour from another. Such an one might declare our marble to be green. He would be quite as right in saying that it is green, as we are in declaring it to be red. Yet then, as the marble cannot can be both green and red, while, as this shows that the quality ‘redness’ must be of our consciousness and not in the marble.

In like manners, since the roundness and the hardness are forms of our consciousness is easy, belonging to the groups that we call sensations of sight and touch. If the surface of the cornea were cylindrical, we should have a very different notion of a round body from that which we possess now. If the strength of the fabric, and the force of the muscles of the body, were increased by some hundredfold, our proportional differences of consistency would possibly equal to that of some upcoming periphery where the marble would be as soft as a pellet of bread crumbs.

Not only is it obvious that all these qualities are in us, but, if you will try, you will find it quite impossible to conceive of ‘blueness,’ ‘roundness,’ and ‘hardness’ as existing without a call for such consciousness, his frame reference is to some such consciousness as our own. Saying that even the might seem strange ‘singleness’ of the marble is about us, but simple experiments will show that this is veritably the case, and that our two most trustworthy senses may be made to contradict one another on this notable point. Hold the marble between the finger and thumb, and look at it in the ordinary way. Sight and touch agree that it is single. Now squint, and sight tells you that there are two marbles, while touch asserts that there is only one. Next, return the eyes to their natural position, and, having crossed the forefinger and the middle finger, put the marble between their tips. Then touch will declare that there are two marbles, while the naked eye says that there is only one. Our sense of touch proclaims our belief, however when we appear to it, just as imperatively as the naked eye does.

Nevertheless, it may be said, the marble takes up a certain space that could not be occupied, while, by anything else. In other words, the marble has the primary quality of matter, extension. Surely this quality must be in the thing and not in our minds? Nonetheless, the reply must still be; whatever may, or may not, exist in the thing, all that we can know of these qualities is a state of consciousness. What we call extension is a consciousness of a relation between two, or more, affections of the sense of sight, or of touch. It is wholly inconceivable that what we call extension, is the branch of a progressional contingence and should exist independently of consciousness, as we knew it to be. Whether, this is inconceivability, it does so exist, or not, is a point on which I offer no opinion. Thus, whatever our marble may be, all that we can know of it is under the shape of a bundle of our own consciousness.

Nor is our knowledge of anything we know or feel more, or less, than a knowledge of states of consciousness. Our whole life is made up of such states. Some of these relational states as inferred by its cause we call ‘self’, and others to the cause or causes that may be comprehended under the title of ‘not-self.’ Nonetheless, inform that holds the existence neither of ‘self’ nor of that of which is ‘not-being-of-self’ have or can that we by any possibility have, any such unquestionable and immediate certainty, that we have of our relational states of consciousness, under which we can consider having been their effects. They are not immediately observed facts, but results of the application of the law of causation to those facts. Strictly speaking, the existence of a ‘self’ and of a ‘not-self’ are hypotheses by which we account for the facts of consciousness. They stand upon the same footing as the belief in the general trustworthiness of memory, and in the general constancy about A Nature-as hypothetical literature or academic summations for which acquires its doctorate to be acquainted and familiarized about its defending dissertation, only to be proven, or known with by way of its highest degree of certainty given by immediate consciousness, which, is, nevertheless, of the highest practical value, since the conclusions logically drawn are from them are always verifiably experienced.

This, in my judgment, is the ultimate issue of Descartes' argument, bearing to point out that we have left Descartes himself some way behind us. He stopped at the famous formula, ‘I think, therefore I am.’ Yet, the concerning considerations will show this formula to be full of intertwining fibres and verbal dissimulations that only assimilates entanglement. In the first place, the conclusive ly idealistic term said to be, ‘therefore’ which has no deserving business, and must legitimately find its way home. Also, ‘I am’ of being assume in that ‘I think’, may from which it is simply another way of saying ‘I am thinking’ or ‘I am conscious.’ All the same, it is in the second place, ‘I think’ which is not one simple proposition, it is, that there are three distinct assertions rolled into one. The first of these is, something called ‘I exist,’ the second is, something called ’thought exists’ and the third is, ‘the thought is the result of the action of I-ness.’

Now, it will be obvious to you, that the only one of these three propositions that can stand the Cartesian test of certainty is the second. It cannot be doubted, for the very doubt is an existent thought. However, the first and third, whether true or not, may be doubted, and have been doubted. For the assenter may be asked, How do you know that thought is not self-existent, or that a given thought is not to affect of its previous line of thinking, or given to something otherwise to some external power? A diversity of other questions, much more easily put than answered. Descartes, determined as he was to strip off all the garments that the intellect weaves for itself, forgot this gossamer shirt of the ‘self’ bringing of a greater detriment, and the ruin of his expression when he began to clothe himself again.

Nevertheless, it is beside my purpose to dwell upon the minor peculiarities of the Cartesian philosophy. All I wish to put clearly before your minds thus far, is that Descartes, having commenced by declaring doubt to be a duty, found certainty in consciousness alone; and that the necessary outcome of his views is what may properly be termed Idealism; namely, the doctrine that, whatever the universe may be, all we can know of it is the picture presented to us by consciousness. This picture may be a true likeness–though how this can be is inconceivable; It may have no more resemblance to its cause than one of Bach's fugues has to the person who is playing it, than a piece of poetry has to the mouth and lips of a reciter. It is enough for all the practical purposes of human existence if we find that our trust in the representations of consciousness is verified by results. That, by their help, we are enabled ‘to walk surefooted in this life.’

Thus the method, or path that leads to truth, showed by Descartes, takes us straight to the Critical Idealism of his great successor Kant. It is that Idealism that declares the ultimate fact of all knowledge to be consciousness, or, in other words, a mental phenomenon. Consequently, affirms the highest of all certainties, and the only absolute certainty, to be the existence of mind. However, it is moreover that Idealism that refuses to make any speculative assertions, either positive or negative, find there parallel in what lies beyond consciousness. It accuses the subtle Berkeley of stepping beyond the limits of knowledge when he declared that a substance of matter does not exist. Existence may paradoxically be for not as the arguments for which he is supposed to have vanquished into the Northern sea, but reasons hold to its existence for the sake of matter itself, only from which we were equally destructive to the existence of soul. Nevertheless, it refuses to listen to the jargon of more recent days about the ‘Absolute’ and all the other hypostasised adjectives, the initial letters of the names of which is generally printed are the capital letters, just as you give a Grenadier a bearskin cap, it much seems as to give the appearance of ponderosity for more than he is by nature.

The path indicated and followed by Descartes, which we have previously been treading, leads through doubt to that critical Idealism that lies at the heart of modern metaphysical thought. Yet the ‘Discourse’ shows us another, and apparently very different, the path, which leads, quite as definitely, to that correlation of all the phenomena of the universe with matter and motion, which lies at the heart of modern physical thought, that most people call Materialism.

The early part of the seventeenth century, when Descartes reached manhood, is an epoch of the intellectual life of manhood. Then, physical science suddenly strode into the arena of public and familiar thought, and openly challenged not only Philosophy and the Church, but that common ignorance that often passes by the name of Common Sense. The assertion of the motion of the earth was a defiance to all three, and Physical Science threw down her glove by the hand of Galileo.

Thinking of the immediate result of the combat is not pleasant, to see the defender of science, old, worn, and on his knees before the Cardinal Inquisitor, signing his name to what only he knew to be a lie. No doubt, the Cardinals rubbed their hands as they thought of themselves to how well they had silenced and discredited their adversary. Still, two hundred years have passed, and have long since diminished of any but one feeble or erroneous combatant. Physical Science sits crowned and enthroned as one legitimate ruler of the world in thought. Charity children would be ashamed not to know that the earth moves; while the Schoolmen are forgotten; and the Cardinals–well, the Cardinals are at the Ecumenical Council, still at their old business of trying to stop the movement of the world.

According to Descartes, if we make errors in our thinking, it is our own fault. Human beings are given to a free will, and most substantially significant, and just a flawless part of our species. This free will acts independently to either affirm or deny, or pursue or shun any some thing. The free will acts properly when the will has access to knowledge and reason and can ‘perceive what is true with sufficient clarity and distinctness.’ To attain truth, and to act correctly, the will must rely on those perceptions that cannot come from anything, but rather, come from something, and that something must be from God in all his supreme perfection. God, in essence, must play the celestial orchestrator in any perception that is true. Following this path cannot lead one to err; that is, the path of humility that relies on one's God-given faculties and God himself to use the will properly.

On the other hand, if freedom calls of the will, it is confronted with something of which it has no knowledge, it will act indifferently. Without God and the knowledge of what is true, the will ‘easily turns away from the true and the good,’ leading to deception and sin. In addition, use of the will with only partial knowledge, that is, without full clarity and distinct perception based on knowledge, will also lead to error. Indifference and conjecturing or making speculative assertions are not true or false, it is a misuse of the will, even if by the change of chance it could possible take or give oneself of luck, the outcome happens upon the truth. The deliberation from illiteracy, is one who arrogantly relies only upon then immigrated transitions for which all unexcepted modulations in doings, occurs from those that are without truth only inaccessibly from God, thus, the make-upon of some unequivocal misuse of free will, are ultimately and undeniably, as merely of an error.

Spinoza would disagree with Descartes' idea of the free will. While the will for Descartes uses the intellect freely (in the proper way), Spinoza asserts that ‘things could not have been produced by God in any other way or in other order than is the case.’ The will is not a free cause, but a necessary cause, because it is only a ‘definite mode of thinking’ and thus subject to the greater causal matrix. Since all causes in the matrix can be followed back to God as an absolutely infinite being, everything has its cause in God. While, not even God has freedom of the will, as he is constrained by his divine nature and can only act as his nature would have it-the only way it can be as it is perfectly so. Therefore, there are no error, no sin, and no deception. Everything simply is as it should be according to the perfection of God's divine nature.

Substance is defined differently for Descartes, Spinoza and Leibniz contributing to the fundamental differences between their assertions in their philosophies. For Descartes, there are primarily three substances: God, thought and extension. For Spinoza there is only one substance: God. For Leibniz, there are two substances: God and monads. For each of these three, their concept of substance dramatically affects the outcomes of their philosophies and their explanations for the nature of the universe and our place in humanely, and we might consider ourselves as inseparable of it, and in our relation to God.

Descartes' determination foreshadows to carry through his need to readily rethink along everything he has ever thought to be True and Right. In doing so, he realizes that the only thing he can really be sure of is his ability to think, thus affirming his existence, and the substance of thought. He bears to witness in the conditions of truth that he is in himself from that which is a prefect God, and that God must be both omnipotent and benevolent. He can then determine that because God is not a great deceiver (deception is an attribute of imperfection not consistent with perfection), then extension is the third substance. There are some discussions regarding the ability of the two substances, thought and extension, to interact. Since effect can be caused by only the same kind of substance, having it of some connotation for being causally then seems impossible for thought and effectual of the body. However, Descartes asserts that at the smallest levels interaction does occur.

Spinoza criticizes Descartes for not following through on his assertions about an infinite God. If God is infinite, then he must be absolutely infinite, that is ‘substance consisting of infinite attributes, each of which expresses eternal and infinite essence.’ Because God is also perfect in his divine nature, everything that is, is by that perfection and is only exactly as it can be. God, thought and extensions are not separate substances, but rather thought and extension are simply attributes of God, expressed through an infinite amount of finite modalities. The order and connection between thoughts correspond and those for extended things (as they are the same) according to an infinite causal matrix determined by God, the only absolutely infinite substance.

Leibniz appeals to God as not only worthy of glory for his greatness and goodness, but his ability to create the most interesting reality from the simplest system. Leibniz proposes that God perpetuate this creation and by its infinite number in that of ‘monads.’ Each monads are a singular substance that ‘expresses the whole universe in its own way, and that all events, with all their circumstances and the whole sequence of external things, is included in its notion.’ There is a hierarchy of monads from the most simple and most confused, to the minds that are self-conscious and reflective, thus much less confused. When the perceptions of these infinite number of minds (monads) harmonize, the world arises as an emergent property based on well-founded phenomenons. Monads have no windows, that is, they do not interact. Nevertheless, again, they don't need to as each substance has within it a complete notion of itself. There is not a problem with the interaction of thought and extension, because there are only ‘monads.’

Knowledge for Locke is the perception of the agreement or disagreement of ideas. Ideas are the object of thinking, and come from sensation and reflection. It is the quality of a subject that has the power to produce ideas in one's mind. Experience provides the foundation for knowledge as observations about the sensible qualities of the external physical world are perceived through the senses and understanding of the internal operations of one's mind are operations of the mind. Both processes can be reflected upon in one's mind. Ideas are only received via these two methods. The sensation that people are exposed too in a lifetime will affect their ability to both sense and reflect, that is, if they are not exposed they can neither sense nor reflect on sensation they never received, and some people will remain more confused than others about their sense experience and reflection due to their (lack of) focussed and attentively purposed. Further, because reflection requires attention, ideas resulting from reflection only surface later, and, again, to different degrees among different people based on their varied perspective, focus and attention.

Simple ideas can be conceived by means of only one sense, more than one sense, by reflection only, or by all ways of sensation and reflection. Often these simple ideas don't even have a name. The mind is as an ‘empty cabinet’ ready for the passive reception of simple ideas. These simple ideas are neither created nor destroyed by the mind, but rather gathered into the mind through the senses or operations as such.

Leibniz believed the intelligible world of ultimate knowables, the problems raised by the skeptic Hume coming after him. He has some words to say to Descartes, who came before Leibniz, was of his concern of whether the world is knowable, but proving that knowledge of the external world is possible so, he foregoes the thrust of his philosophy. He focussed so much on what he believed must be true that stripped-down ideas that leave no point unquestioned, ultimately to prove knowledge impossible, or justify it only after the most extreme doubt possible, was not with what he was concerned. This sector will rather focus on Leibniz's rationalism -his idea that our main apparatus for discovering and understanding the nature of the world comes from pure reason, and not through the senses.

First, Leibniz believed it may have turned out that we did not know necessary truths such as ‘All green things are green.’ How is it that I know this proposition holds, even in some galaxy other than ours, on the other side of the universe? It was akin to a divine sort of magic to Leibniz that we should know any proposition that holds true under all circumstances and locations. He called it ‘an inborn light within us,’ which lets us cross the wide cosmos in one stroke of thought, and know beyond all doubt that all green things have always been green, no matter where on the earth or in the heavens, from the beginning of time to the end of the cosmos.

So let us examine just how we know that all green things are green. We know it because we know if a green thing is not green, it was an error to call it a green thing in the subject, and it is not in fact green. On the other hand, we know that if a thing is green, it is green. Ultimately to deny the proposition would involve us in a contradiction. Let us not forget, that if it is thus to suppose that all examined emeralds have been green. Uniformity would lead us to expect that future emeralds will be green as well. However, now we can define a predicate grue: ‘x’ is gruing if and only if ‘x’ is examined before time ’t’ and is green, or ‘x’ is examined after time ‘t’ and is blue. Let ‘t’ refers to some time around the present. Then if newly examined emeralds are like previous ones in respect of being grue, they will be blue. We prefer blueness as a basis of prediction to glueyness, but why? An interrogative sentence, by its appearing involvements as a reference to a difference, this is just a parochial or language-relative judgement, there brings no language-independent standard of similarity to which to appeal. Other philosophers have not been convinced by this degree of linguistic relativism. What remains clear is that the possibility of these ‘bent’ predicates puts a decisive obstacle in face of purely logical and syntactical approaches to problems of ‘confirmation.’ So we know now as well of the place that given to respect may not otherwise be true, or that there are such things as true contradictions. Nevertheless, we know there are no such things as true contradictions, and so we know that all green things are green.

Consequently the interrogative sentence comes to the boiling point from which its availabilities to answer of ‘how’ do we know there are no trued contradictions? We cannot prove this is true without assuming its truth in the first place, for any demonstration of any proposition is valid only if there are no true contradictions -the very things we are trying to prove. So to avoid begging the question, we cannot reason at all. That there are no true contradictions, then, cannot be demonstrated.

How do we know there are no true contradictions? That is, would we know it if it were merely a quirk of our minds that we cannot comprehend a true contradiction, some arbitrary way our brains developed, that has nothing to do with objective reality? Could it be that we cannot simply conceive of a true contradiction in the way that our bodies cannot be sustained by eating stones? Is it merely an arbitrary aspect of the human organism that we cannot conceive of a true contradiction, than this being due to the nature of the world itself?

One would never know this if it were so. We would go on reasoning and making rules of deductive logic that have nothing to do with what is true and false in nature itself, and only reflect arbitrary quirks of our psychological biology, so to speak, and what it can and cannot process as an organism that thinks.

Nevertheless, most philosophers do not think there is much fruit to be had in thinking like this. To question the rule of non-contradictorily, that is, to deny its truth, rests upon assuming its truth as much as asserting its truth does. Aristotle solved the problem by saying if a man doubts that there are no true contradictions, if he speaks and reasons, he is assuming the principle's truth; so if he questions it let him remain silent, but if he speaks and argues he must assume there are no true contradictions to do so, and thus undermines his doubt of the principle. Put another way: we have no choice but to assume there is no true contradiction if we are to philosophize at all; for whether we use reason to deny the rule of non-contradiction or to assert its truth we are all asserting its truth as a prerequisite. This very discussion of the problem assumes the rule's truth, and so where I question its validity here, ironically, I assert its veracity, by the mere fact that I am using reason.

So let us do what we must, and assume that it is complementary for the sake as drawn upon that we who infer that nature has some consistency of things. In themselves, we have in ruling of non-contradiction, for which case, are we to know of its truth? We, on the other hand, cannot explain in how we know it, only that we cannot conceive throughout in other respects. This is the ‘inborn light within us’ that allows us to cross time and space and know the nature of the other side of the cosmos, which Leibniz found so fascinating. Assuming the rule of non-contradiction is commentary on the true nature of things, it is certainly astounding that we should find a single principle that should apply to all places, times, dimensions and modes of being, from a mere act of thought. Certainly were the empiricist correct, but they would have a very difficult time explaining just how this ‘inborn light’ is possible. To say, that we have evolved as such as that we have become rationally ingested as to arrange by coordinative orders a set of communicative combinations that once had been lacking the ability to conceive of a true contradiction, into which realms are arbitrarily biological quirks, that place the origin set to a certain position that positioned by its growth was held steadfast within the strangest formalities as set through causality, least of mention, that, in so doing, its resulting consequent from arbitrary displacement drew nothing but a marginal peripheral infraction of nature. To do so would be to question the objective veracity of the principle; perhaps we can just survive and leave more offspring if we believed there were no true contradictions, though it is not in fact true that there are none. Certainly to call it a result of evolution is to deny the very veracity of the principle, something impossible in philosophy if it is to be philosophy. Evolution works by preserving the ones who leave the most offspring, not preserving the ones who know the most truth.

Before Kant, philosophy had two categories of knowledge: those propositions we know whose contrary implies a contradiction in terms, and those whose contrary didn't. ‘This apple is yellow’ doesn't have a contrary that implies a contradiction, while ‘All apples are apples’ does. Leibniz naturally found it more incredible that we could know the latter rather than the former; the former has no bearing on anything but that particular apple; it does not signify anything beyond the particular circumstance it describes. ‘All apples are apples,’ however, hold true from the foundation of the cosmos to its end, in every time and place there is. This was substantive knowledge to Leibniz. According to Leibniz it is the principle found in such universal knowledge that allowed us to use the senses, rather than the senses being the source of our knowledge. Without pure reason, to Leibniz, sense experience would be worthless; we could never progress in knowledge without the eternal principles of analytic reason, with which we analyse and process this sensory data. The senses are subject to doubt as well; they may all be dreams and fictions, while whether I am dreaming or awake if I think to myself ‘All apples are apples’ the proposition yet holds true, and I know it to be so, whether it occurs to me as I am dreaming, or hallucinating or whatever.

Sometimes a philosopher like Hume will propound a skepticism that makes us doubt whether we can even know what the philosopher himself is arguing, if he is right and we really know that little. But equally, empiricist like Hume betray the veracity of rationalism: Hume, after all, did not show us movies to teach us, he wrote books. If pure reason is worthless, and, least of mention, matters of the sense are only the avenues of our understanding, how is it we are to learn just by following Hume's path of reason? Wouldn't he do better to show us pictures and images? After all, all reasoning, Hume's reasoning even, comes in logical form, comes in words and not images, the stuff of thought. Hume's very enterprise of reasoning his way into showing reason worthless itself betrays the value of reason. Never mind that it was mostly inductive reason; if logic and pure reason were worthless, wherefore does Hume write, filling hundreds of pages of logical processes? We might say to him that he has an awful lot to say about what must be true, for someone who believes we cannot know the truth. In addition he employs logic and reasons quite extensively, for someone who believes pure reason can give us no substantive truth.

Leibniz saw quite correctly that, though sense experience is probably essential to human nature, and necessary for us to mature our minds in the first place, it is reason that gives us the perspective and principles to use such experiential sense-data. If I should know that a particular apple is green, and a thousand other data of the daily sights and sounds, without logic, reason and mathematics, by which I process and analyse and organize such data, none of our sciences would be possible, least of all philosophy, but the physical sciences of nature also. Sense-data contains the raw facts of the world, and, nonetheless, its found knowledge comes about when the principles in universal rules of reason are used to process such facts into knowing what we do not perceive, are they things like the centre of the Earth or the nature of the infant cosmos. Without universal principles, are they creative inductions like scientific theories, or the deductive rules of logic, sense data would get us nowhere—add fact to fact all one's life, without rational analysis, without using the tools of the ‘inborn light within us,’ and knowledge would be impossible. I am not so much arguing that was there no sense data there would be in fact knowledge, but only that both are required, that reason conductively deduces through sense-data and sense-data bears its fruit by means of reason, in a two-way process, both sides of which are often essential.

Psychologists today would no doubt insist that psychology be a discipline separate and distinct from that of philosophy. The mere fact that psychology is thought of as a science sets it apart from philosophy and, at times, makes it quite incompatible with philosophy. Yet psychology and philosophy are bound by history in that it is from philosophy that psychology receives the methods that psychology employs in analysing and evaluating the mind and all that it entails. Psychology owes its existence to most philosophical thinkers including Aristotle, Plato, John Locke, and David Hume. Here, our immediate focus on the particular influences of Rationalism, is specifically focussing on the work of René Descartes and the counterarguments of Emmanuel Kant.

René Descartes was a very private man and the details of his life are only vaguely known. Born in 1596, he was an intellectually bright child and was enrolled in the College at la Flèche at the age of 10. Some time after graduating at the age of sixteen, Descartes took up residence in the Paris suburb of St. Germain. Here, between periods of seclusion, Descartes observed the workings of a set of mechanical fountain statues built for the Queen. Watching these, he developed an idea that real bodies, animal and human, operate much like these automatautilizing a system of hydraulics and fluids to animate the body and its processes. This would be the basic idea involved in his later physiological theories of the brain and visual perceptivity (Fancher, 1979).

After moving and becomingly reclusive again, Descartes found himself dissatisfied with the uncertainties of much of the information he had learned in school and afterward. He was pleased with the certainties that mathematics offered, but as of yet there were not many ways to apply math to other disciplines. One morning during these frustrations, Descartes found himself watching a fly on the wall (or so the story goes) and suddenly discovered that he could define the fly’s position using only three numbers: the perpendicular distance of the fly from each wall and from the ceiling. Generalizing from this realization, he discovered that any point in space could be defined in a similar way by measuring their distances from perpendicular lines or planes. These numbers have commonly become known as ‘Cartesian coordinates’ and the perpendicular lines as the x -and y-axes. That discovery led to the development of analytical geometry, the first mathematical blending of algebra and geometry. The discovery of the coordinate plane, alone, is a huge contribution to psychology, for without it, defining the relationship between independent and dependent variables, calculating correlations, doing tests of significance, and other quantitative analysis would not be possible (Fancher, 1979)

After this discovery, Descartes began to wonder if there were other knowledge areas that could give answers or facts that provide the same amount of certainty as their results made to mathematics. Able to think of none, he proceeded with enumerating the faults of then-current scholarship and ultimately concluded that the best course for him to follow would be to disregard everything he had learned and only accept as ‘truth’ those things that he could determine were correct or valid through his own systematic reasoning. To this end, Descartes formed a method for such reasoning that he believed would offer other disciplines the same amount of certainty afforded by mathematics. This method consisted of four rules, stated briefly they are: (1) To proceed by means of doubt, to take nothing for granted, to avoid bias and prejudgment; (2) its distributive subject matter for which the argument becomes that which are the simplest parts; (3) as to the total proceeding in each related stage soon becomes the simple, and, of course, leading to the more complex; (4) To ‘enumerate’ and review to make sure nothing is missed in the argument, and that as many sources for the correct conclusion as possible may be collated.

Descartes was sure that this method would provide the mathematical elements needed to produce valid and reliable results in scholarly thinking. The first rule of this method, however, was especially troubling to Descartes. Already plagued with doubt about many other supposed truths, Descartes began to doubt everything until he even doubted that he existed. After a long process of doubting and reasoning, he doubted his existence until he realized the only thing he could no longer doubt was that he doubted. He reasoned that because he could not doubt that he was presently doubting, he must at least exist to be doubting. It is from this doubting, and subsequent realization and affirmation of existence we obtain the oft-quoted ‘I think, therefore I am,’ or ‘Cogito, ergo sum’ (Balz, 1952.) By proving that he existed, Descartes reasoned that he could also prove other things to be logically and rationally true by using the method he created.

Like the development of analytical geometry, the ideas contained in his methodology constitute a large contribution to the future of psychology in that it is precisely from the principles Descartes laid out in his method that deductive and inductive reasoning developed. What is more important, the introduction of methodology for the precise and systematic evaluation and verification if ideas or supposition was crucial to the development of the field of science, to an over-all picture, for much had been attributed to psychology? Descartes’ method provides the fundamental building blocks of the scientific method that modern science heralds as the marrow core in of all procedural guidelines. We, like Descartes, are satisfied that if all of the rules of the scientific method are followed exactly, the results should be valid and dependable.

Descartes made yet another important contribution to the future field of psychology immediately after his realization that he did exist. As he made this realization, he also realized that he could be sure that the mind and body were separate from one to conclude, in that I was a thing or substance whose whole essence or nature was only to think, and, to exist does not need space nor of any material thing or body. Thus, it follows that this ego, this mind, this soul, by which I am what I am, is entirely distinct from the body and am easier to know than the latter, and that even if the body were not, the soul would not cease to be all that it now is.

This was an important distinction at this time, for most of the discourse had concerned the workings of the soul with the assumption that the soul controlled most aspects of the body. It had been supposed that the soul was the seat of all reasoning, thought, memory, and so on, and the animating force within the body. It is not until Descartes that the mind is ascribed with the powers of reasoning, knowledge, and emotion separate from the functioning of the rest of the body. For Descartes, the body functions independently from the mind, however the mind and body can interact to produce varying results in behaviour. Although he does still discuss his mind as part of the soul, what is important is that Descartes uses and continues to develop the concept of the rational, thinking mind for being separate and distinct from the body. This mind-body distinction is obviously an important one for psychology, allowing for the development of much of physiological psychology with cognitive and perceptual psychology, among others.

This mind/body split led Descartes to make further conclusions about how the brain functioned. His primary concerns was the workings of vision and visual perception. Descartes concluded that, based on a previously discovered ‘truth’ that everything is in motion, light and objects give off tiny vibrations and these vibrations press upon various areas of the eye. This then causes the vibrations to move through the eye to stimulate a series of hollow nerves through which essential brain fluids flow. Much like the automata from St. Germain, Descartes envisioned that these brain fluids flowed through the nerves stimulated to constrict or expand by the vibrations of the objects being viewed so that a sort of stamp was of what was seen was created in the brain. Reasoning that because we have two eyes but only seem to perceive any object we are viewing as singular, he further concluded that there must be a centre in the brain in which the vibrations from both eyes meet to create a singular image. For Descartes, this area was the Pineal gland because it entered the brain and not literalised like the rest of the brain. It was also here, he concluded, that the soul resided.

Although much of how Descartes reasoned, the mind to work was incorrect, some basic ideas were fundamental for future work on perception and physiological psychology. Among the important ideas is Descartes’ graphing of the visual field of perception that showed that each eye not only perceives what is directly in front of it, but also receives sense information from the outer field of the opposite eye (essentially that we see much in the left side of our visual field with our right eye and vice versa). Also, though he was wrong about the vibrations and hollow nerve tubes, he was correct in reasoning that there must be some centre in the brain where the images from both eyes are combined into a singular image to be consciously dealt with by the mind.

Descartes evidently had a profound impact on ways of thinking about the world and that this impact is still seen in much of modern psychology. However, these ideas in and of themselves did little to further the cause of Psychology, for Descartes’ method of ascertaining the truth by reason alone left out an entire realm of discussion that dealt not with how the senses perceived, but what the senses perceived. Indeed, the tenets of rationalism stated that sensory information was likely to be false and unreliable and summarily dismissed it from further discussion. There was a second group of thinkers, however, who viewed sensory information and experiences as the only accurate measurements of and indicators of ‘truth,’ as this group was called the empiricist.

Basic rationalism teaches of: (1) Don’t trust senses, since they sometimes mislead, knowingly; since the ‘knowledge’ they provide is inferior (because it changes; (2). Reason alone can provide knowledge. Math is the paradigm of real knowledge. (3) There are innate ideas, e.g., Plato’s Forms, or Descartes’ concepts of self, substance, and identity. (4) The self is real and discernable through immediate intellectual intuition (Cogito ergo sum). (5) Moral notions are comfortably grounded in an objective standard external to self -in God, or Form. Basic empirics’ precepts were as of (A) senses is the primary, or only, a source of knowledge of the world. Psychological atomism. (B). Mathematics deals only with relations of ideas (tautologies); gives no knowledge of the world. © No innate ideas (though Berkeley accepts Cartesian self). General or complex ideas are derived by abstraction from simple ones (conceptualism). (D). Hume -there’s no immediate intellectual intuition of self. The concept of ‘Self’ is not supported by sensations either. (E) Hume -no sensations support the notion of necessary connections between causes and effects, or the notion that the future will resemble the past. (F) Hume -‘is,’ that does not imply to ‘ought’ for each their source of morality is feeling.

Although both of thee schools of thought believed that truth was attainable, they disagreed about the role that the senses played in discovering this truth. The rationalists employed deductive reasoning, reasoning that does not depend on experience to inform it (for example concepts and constructs such as bachelor or death that do not require certain experiences to be understood) to attain truths. The empiricist utilized empirical reasoning, reasoning that depends upon experience or contingent events in the world to inform it (that George Bush, Jr. is president in 2004 cannot be determined by examining the concepts of ‘president’ and ‘George Bush’). This disagreement over which type of reasoning was superior continued until the 1780’s when Emmanuel Kant, a German philosopher, began publishing his most influential works.

Kant’s work was primarily a reaction against the work of the empiricist David Hume. He found problems with both the empiricist and the rationalists, however. Essentially Kant proposed that neither rationalism nor empiricism were sufficient, or correct, in determining absolute truths for there were truths that neither of these two schools could prove as such by only using inductively and theoretical reasoning. Moreover, both modes of thought contained flaws that allowed two contradictory statements, or autonomies, to both be accepted as true and valid.

Kant argues that while both rationalism and empiricism assume that obtaining knowledge of how things really are is possible, as opposed to how they seem to us, they overlook the fact that the human mind is limited. The human can experience and imagine only within certain constraints; the human mind has a hand in constructing and shaping our reality as we perceive and think about it. Specifically, these constraints are synthetic and deductively. Synthetic deductive truths, which include location in space and time, causality, experiencing self, thing-ness, and identity, does not depend on experience to be realized but also cannot be arrived at by the same kind of logical reasoning used by the rationalists. Neither of the two schools of thought was equipped to deal with these kinds of truths.

The solution to this problem, Kant argued, was to understand that the world we experience must be distinguished into two categories -the noumenal, or external world, and the phenomenal, or an internal world. The noumenal world consists of ‘things-in-themselves,’ objects, as they exist in their pure and unfiltered form. However, Kant warns, the noumenal world can never be known directly because once it is perceived by the human mind it passes into the phenomenal world. What humans experience is not the actual world, but a re-creation, an interactive experience, of the world (Fancher, 1979) In this way, Kant argues that the mind is an active agent in how we perceive and interact with the world; it creates reality just as much as it perceives it.

Through this argument, Kant creates a melding of the two schools of thought-rationalism and empiricism. He verifies the methods of the empiricists, in his agreement that of all that we perceive, think about, and thus know, is filtered through our senses and experience. Empiricism is complicated however, when Kant also insists that our mind create and interprets experience and ‘reality’ as it perceives it, and therefore rational reasoning must also be employed to ascertain several truths. It is only through combining these two methods that most truths may eventually be realized.

The extensive contributions of Descartes and the rationalists provided many ideas and distinctions that necessarily predicated Kant’s philosophical works. Especially important was the mind/body distinction and the development of the idea that mind and body could interact with one another. Kant, by arguing that a cohesive and valid science would not be possible unless the conditions of his synthetic deductive reasoning were met, encouraged, if not forced, the melding of the rationalist and empiricist modes of thought into one that allowed for both sensory experiences and reasoning, together, to provide the basis of ‘truth.’ However, perhaps the most important contribution to psychology is that all of this culminated in the new idea that the mind creates reality just as much as it perceives it. This idea paved the way for, indeed, created the need for a more exact study of the mind. With these new ideas in hand, and the previous obstacles to thinking removed, it would be less than a hundred years later that the first experimental psychology labs would be established and psychology would begin to flourish as a science.

Friedrich Nietzsche is not only one of the most influential philosophers the world has seen, but he is also one of the most controversial. He has influenced the twentieth century thought more than almost any other thinker. In his numerous works, Nietzsche constantly criticizes and restructures the strongly held philosophical and religious beliefs of his time. One such principle that he refutes belongs to his predecessor Rene' Descartes, and concerns the apparent distinction and significance of the human mind over the body. Descartes explains this elaborate theory in his Meditations on First Philosophy, claiming that the mind (the conscious) is the lone essential part of the human essence. On the other hand, Nietzsche stated via his manifestation through which all dynamic contributes are functionally of his distributive order as set further ahead by his work, On the Genealogy of Morality, his beliefs that the body (the unconscious) is key to the human essence. One may find it difficult to decide between these two ideas, for both philosophers pose good arguments on the contradicting sides of this famous dilemma.

However, by analysing them further, I realize that the qualities of their arguments are only as good as the foundations upon which they are based; one cannot have an understanding of the mind or the body without first having knowledge of the essence of human existence. Consequently, I will prove that the body is superior to the mind by showing that the centre for Nietzsche's ideas, the human essence, is more valid than that of Descartes.

Descartes' idea of the human essence is based solely on his formed concept of ‘radical doubt.’ He believes the essence of human existence to be simply ‘a thinking thing.’ We must now analyse how he arrived at this conclusion. Descartes is famous for radical doubt, a concept that questions everything, and assumes nothing to be true unless it can be proved so with his idea of ‘clear and distinct perception.’ From this he states that the only thing he can clearly and distinctively perceive is that ‘I exist.’ He concludes that since he ceases to exist when he ceases to think, he can then clearly and distinctively call himself a ‘thinking thing.’ Descartes explains this train of thought when he says: From the fact that I know that I exist, and that while I judge that obviously nothing else belongs to my nature or essence except that I am a thinking thing, I rightly conclude that my essence consists entirely in my being a thinking thing. Although perhaps I have a body that is very closely joined to me, nevertheless, because on the one hand I have a clear and distinct idea of myself, insofar as I am merely a thinking thing and not an extended thing, and because on the other hand I have a distinct idea of a body, insofar as it is merely an extended thing and not a thinking thing, it is certain that I am really distinct from my body, and can exist without it.

Descartes’ arrival of the human essence as a ‘thinking thing’ in this way is obviously fully based on his beliefs of radical doubt and clear and distinct perception. He bases all of his inferences on other inferences.

Descartes also devaluates the human body and places the mind at the essence of the human existence based on his concept. Due to his radical doubt, Descartes quickly omits the body and the entire physical world as having any significance because of the simple fact that they can be doubted. He establishes a strong sense of doubt in his senses, because, according to Descartes, one cannot know clearly and distinctly that they are not being deceived into their physical sensations. Descartes thus condemns the significance of the body when he proclaims that it is ‘not a substance endowed with understanding.’ He places the body into the physical, unintelligible realm of his concept of dualism, opposite from the thinking, knowledgeable realm. Descartes now acknowledges the body for being useful only within the limits of ‘moving from one place to another, of taking on various shapes, and so on.’ It is from this condemnation of the body into the physical, unintelligible realm that Descartes further places the mind on a pedestal, and at the essence of human existence. To him the mind is superior because it thinks, which is our essence. He explains this in the indented quote I have already cited, saying that the mind can exist without the body. Analysing things with radical doubt clearly finalizes all of Descartes' ideas.

Therefore, Descartes' argument is not valid because of the fact that it is solely derived from assumptions. His idea of the superiority of the mind is based on the assumption that humans are thinking things, which it is based on the assumption of clear and distinct perception, which is further based on the assumption that radical doubt is valid. Descartes' entire argument includes the use of clear and distinct perception, a concept that he concocted, to evaluate what is true and what is false. Dubbing something valid when it is absurd based on an assumption, let alone many assumptions. Subsequently, it is false to grant Descartes' ideas any relevance because they are derived by judging things on his basis. Steven J. Wagner, in his essay ‘Descartes's Arguments for Mind-Body Distinctness,’ lends us support, at which this point becomes of us, as of when we are to believe of its good or the contrarieties of bad, that the proponents as gestured by our understanding were by him to say of: ‘Descartes's procedure only makes good sense once we see it as a product of his system. Too much in Descartes depends on things that are far too wrong.’ He explains that Cartesian (Descartes' thinking) dualism and the Cartesian mind can only be supported along Cartesian lines. It requires little intelligence to prove a point when one bases their argument for it on invalid theories of their own fabrication. The superiority of the mind in the human essence, therefore, has not been clearly proven because its ideal is based on Descartes' numerous assumptions.

Nietzsche's idea of the human essence, on the other hand, clearly holds more validity than Descartes' because it is not based on assumed principles. Nietzsche believes the human essence to be one of the competition, survival and a will to power. Unlike Descartes, Nietzsche's ideal is based on a foundation of facts. He concocts his ideal mostly by observing nature and the world around him. Bertram M. Laing, in his essay ‘The Metaphysics of Nietzsche's Immoralism,’ explains Nietzsche's belief called the ‘organic process,’ whereas the world is ‘a continual distribution and redistribution of force or power.’ Nietzsche, like Freud, attempts to account for the function of consciousness considering the new understanding of unconscious mental functioning. Nietzsche distinguishes between himself and ‘older philosophers’ who do not appreciate the significance of unconscious metal functioning, while Freud distinguishes between the unconscious of philosophers and the unconscious of psychoanalysis. What is missing if the acknowledgement of Nietzsche as philosopher and psychologist whose ideas on unconscious mental functioning have very strong affinities with psychoanalysis, as Freud himself on a number of other occasions, come to acknowledging in a specific and detailed manner an important forerunner of psychoanalysis? Although Freud has stated that Nietzsche’s insights are close to psychoanalysis, very rarely will he state any details regarding the similarities.

At its present state as a specific individual science the awakening of moral observation has become necessary, and people can no longer be spared the cruel sight of the moral dissecting table and its knives and forceps. For here thee rules that science that asks after the origin and history of the so-called moral sensations. Freud ‘who puts aside all his feelings, even his human sympathy, and concentrates his mental forces on the single aim of performing the operation as skilfully as possible.’ [However it] the unconscious must be assumed to be the general basis of psychical life. The unconscious is the true psychical reality, which in its innermost nature it is very much unknown to us as the reality of the external world, and it is as incompletely presented by the data of consciousness as is the external world by the communications of our sense organs, . . . that apart from conscious there are also unconscious psychical processes.

Nietzsche goes on to discuss a number of unconscious thoughts, feelings and motivations that are involved I the feeling of pity. Such unconscious motivations are clearly repressed (inadmissible to consciousness), although the analogy of the foot slipping points to what is unconscious but would be admissible to consciousness. As this example to Nietzsche does not make the specific distinction, but his work is filled with explorations of our emotional states that are commonly regarded as selfless and highly moral but which he demonstrate are involved in our self-enjoyment and self-gratification. Our disguised expressions of sexuality and will to power, while unconsciously denying that this is so and assuaging conscience. Nietzsche was interested in ‘the diverse operations of the conscious and the instinctive.’ In a note from 1870 or 1871, he also wrote, though in a different sense than Freud, that ‘all growth in our knowledge arises out of the making conscious of the unconscious.’

Other than the specific distinction between these systems, every major point of Freud’s, both along with and beyond Lipps, had been explicitly discussed by Nietzsche. Nietzsche was aware of the distinction between unconscious processes that were and were not ‘inadmissible to consciousness.’ It is true that he doesn’t always specifically make the distinction, though he is clearly aware of it.

Nietzsche goes on to a number of unconscious thoughts, feelings and motivations that are involved in the feeling of pity. Such anconeous motivations are clearly repressed (inadmissible to consciousness), least of mention, Nietzsche does not make the distinction, but he writes of both kinds of conscious processes. We call also change one’s mind to that by some early age Nietzsche was interested in ‘the diverse operations of the conscious and the instinctive,’ up to this point he regards conscious and unconscious for their possessives as, ‘subject to different laws of development.’

He certainly did not believe that there was a realm of ‘the things-in-themselves’ as ‘a metaphor for the chaotic and unknowable true world that lay beyond perception.’ The real world is process and change for Nietzsche, as in his later works there is no ‘unknowable true world.’ For one thing, Nietzsche was attempting to get across the point that there is only one world, not two. And that for Nietzsche, if there is anything we contribute to the world, it is the idea of a ‘thing,’ and in Nietzsche’s words, the psychological origin of the belief in things forbids us to speak of ‘things-in-themselves,’ yet points out that in regard to the distinction between ‘appearance’ and ‘reality,’ and what he repudiates is the distinction between and separation of a merely apparent world and a world of ‘true being.’

Once, again, we can consider that Nietzsche clearly thought he uncovered some truths regarding the areas into which he had inquired, whether it be the origin of bad conscience or the psychological motivations of the Apostle Paul. Truth is not illusory but it does unavoidably entail perspectival appearance. For Nietzsche, the apparent world is not cut off from a world of absolute truth. While Nietzsche is quite willing as in his psychological exploration, to draw destinations between ‘deeper’ realities in relation to ‘surface’ appearances, he also argues that on a fundamental level one cannot draw a distinction between a merely apparent world and a perspective-free factual world. The ‘deeper’ realities he discovered cannot be regarded as facts-in-themselves or anything else of the kind that would be free of embeddedness in human schemes, practices, theories, and interpretations, of perspectival seeing and knowing.

Although Nietzsche calls into question the absolute value of truth, values the illusions (the truthful illusions) of art that ae a stimulant to life, values masks, veils and even the creative lie, he also answers the call of truth. Truth calls to us, tempts us to unveil her. If we have integrity we will say ‘Yes’ to the hardest service, surrounding much that we hold dear, including our wishes ‘not to see . . . [what] . . . one does see. When the unveiling takes place to recognize as not truth (or women) in-itself but an appearance that is reality by way of a particular perspective, as one might regard this situation as, among other possibilities an opportunity for the creative play of our interpretive capacities, for the creating and destroying of play, for a creative sublimation of the will to power. But none of this obviates our capacity to sometimes reach what can be reasonably regarded as truth. What it does involve, is for Nietzsche ‘neither a noumenal realm of adjudication for competing truth claims, and perhaps what is most important, Nietzsche introduces the notion that truth is a kind of human practice. This entails ‘local pragmatic truth, truths as good as though Nietzsche does posit transhistorical truth claims given as his claim regarding the will to power. Nietzsche is concerned with what corresponds to or fits the facts, but such facts are not established without a human contribution, without interpretation. Of course, for those for whom the tern ‘fact’ should entail a ‘halt before the factum brutum,’ there may be an objection to the use of such terms as ‘fact, reality,’ and so forth, in such a context.

Nietzsche observes society as a barbaric, predatory world that he separates it into two groups: one having ‘slave morality,’ and the other ‘master morality.’ Those who possess master morality, or noble morality, are the ones who live their lives instinctively by trying to achieve heightened power, often at the expense of others. These people, according to Nietzsche, he, are the active and productive members of society. They exude power and confidence, and prioritize success over popularity. They are the ones who gain the power in the ‘organic process.’ Nietzsche preaches for people to have this kind of morality, for he sees this as ‘good.’ On the other hand, those who possess slave morality are the ones who do not act instinctively and thus are weak. Their weakness is apparent by observing their lack of productivity and success. They became clever to compensate for not being powerful, doing things like congregating for chances of greater defence. These people, according to Nietzsche, developed ‘resentment’ toward their superiors' power. Nietzsche thus calls them ‘the regression of humankind,’ because their morality develops out of hatred and a denial of our bodily instincts. The human essence, therefore, is one of some desires for power and success. Nietzsche cleverly legitimizes this claim by comparing it with the `survival of the fittest' aspects of nature. ‘Beasts of Prey’ hold the qualities of master morality, for they achieve their goals instinctively at the expense of their prey. They do what is needed for them to survive. Lambs, the prey, are equal to those included in Nietzsche's slave morality because they are weak, and congregate in herds for protection. The Beasts of Prey are obviously the ones who survive, so Nietzsche believes that we should strive to act instinctively like them. Rather than following the intimate steps that gaiting from Descartes' would lead by some trivial reason, it is clear that Nietzsche based his concoction of the human essence mostly on irrefutable observations. In this way his idea surpasses Descartes' in relevance and validity, thus giving him clear ground to employ this ideal in proving the superiority of the body.

Finally, Nietzsche uses this valid assertion of the human essence to prove that the body is essential to the human existence than the mind. Nietzsche argues that since the human essence is based on a predatory competition necessary in the ‘organic process’ of the world, the body is more important than the mind. Instinct, he says, is rooted in the body that we are given. Thus our bodies define who we are because they determine to what morality, masters or slave, we cohere. Nietzsche believes that one's placement within these categories is decided at birth as an unalterable ‘assignment’ determined by the genealogy of a person's morals. Our bodies determine whether we act according to our natural instincts for success and the will of power (master morality), or if we turn away from them (mutualist morality). These bodily instincts are the key element to our existence, for they completely govern our personalities. By analysing the Beasts of Prey argument again, it is clear that the lambs were born into their existence as preemptively instinctual, and as well as, primitively defensive from which is in as much as ado about its own obviousness for only being duly given to the physically structured consistency. The bodies of birds have also held to an estranged dissimulation, as of their unmannered instinct. It is likewise that this substantiates the body and is therefore the principal element of our existence. It is the difference between eating, and getting eaten, that Bertram M. Laing describes Nietzsche's ‘body’ when she calls it ‘the source of all inspiration; the power that breathes or speaks through one is not an alien deity, but the self, the man as he really is.’ The body, then, is superior to the mind, because it holds our natural instincts that fully determine who we are and how we will fare in the ‘organic process’ of our existence.

Nietzsche writes: ‘The evidence of the body reveals itself of a tremendous multiplicity,’ Also, ‘Suppose all unity were unity only as an organization? But the thing in which we believe was only invented as a foundation for the various attributes. Similarly: ‘The ‘subject’ is the fiction that many similar states in us are the effect of one substratum.’ Also, for Nietzsche there is no ‘I’ which thinks as a separate entity from the relations which persons have to the world in general. Nietzsche denies that one can suppose any inner thing are from its expressions in relationships. Unity can be attained to a degree, and such unity is highly valued by Nietzsche. But there is no perfect unity through self-creation nor one fixed true self, conscious or unconscious, waiting to be uncovered. And the structure of any ruling unity may at the same time be open to creative self-conflict and possible transformation -: If we are to ‘become who will open ourselves to ‘unremitting transformation -: you must, within a short space of time, pass though and throughout many individuals. The means is unremitting struggles.’ If we allow ourselves to have access to, and develop and utilize, more affects and more eyes, different eyes, we may be on the way to passing though and throughout many individuals. Such possibilities may be both potentially enriching and dangerous.

Had Wittgenstein ever had at any time feel to have to do with to write about himself, this apparently most ‘intellectuals’ of philosophers might have said: I have always thought with my whole body and my whole life. I do not know what purely intellectual problems are. You know these things by way of thinking, yet your thought is not your experience but the reverberation of the experience of others, as your room trembles when a carriage passes. I am sitting in that carriage, and as often, I am the carriage.

Although written by Nietzsche, Wittgenstein’s work is none the less suffused with authentic pathos, and it will be seen as an integral pat of the tragically self-destructive design of European thought.

In the First Meditation, Rene Descartes is to bring of a certain state, the question what he knows. He convinces himself that his senses cannot be trusted and that all his experiences may be nothing more than mere dreams. Descartes finally concludes that he may not know anything, not even the fact that he has a physical body

His Second Meditation focuses on the finding, in at least, of a single truth, or the intuitive certainty under which he can hold onto. In his quest for this certainty, Descartes rejects ‘whatever admits of the least doubt, just as if [he] found it to be wholly false.’ He even concedes perhaps ‘that nothing is.’ But Descartes is not so easily defeated. He convinces himself that he exists as a thing that thinks, in other words, a ‘thinking thing.’

How does Descartes reach such an unyielding conclusion? He first proves that despite all his uncertainties, he actually exists. His notion that all physical objects do not exist precludes him from having a body to prove his existence. Instead, Descartes argues that due to the very fact that he has these notions prove that ‘I’ exist. ‘But if I did convince myself of anything, I must have existed.’ He argues that even if deceived by and all-power being then he must also exist because, ‘[the deceiver] will never bring it about that, at the time of thinking that I am something, I am in fact nothing.’ Thus Descartes concludes that ‘I am’, ‘I exist’ is necessarily true whenever he conceives it in his head.

But what does Descartes mean by his expressing gesture of ‘I-ness’, of course, as might be expected, it was meant for himself. It certainly cannot be a body since he believes all physical objects to be mere illusions. Without the body, there can be no such things as nutrition, location motion or sensation. The only immovable attribute he can find that does not require his physical body is his consciousness or experience. He goes far to say that ‘maybe, if I wholly ceased from experiencing, I should at once wholly ceases to be.’ Furthermore, he says that ‘‘I am’ precisely taken refers only to a conscious being; that is a mind, a soul, an intellect, a reason.’ It is this consciousness that allows him see what is necessarily true. He argues that physical objects and attributes are not really perceived by the senses, but only by intellect and by being understood. Descartes concludes his argument by suggesting that it be as obviously perceived by his own mind through intellect and understanding. Thus he proves he knows that he exists of a thinking thing that experiences.

There are many different points in Descartes’ arguments. Some are more powerful than others but I believe his construct of an all-powerful deceiver is a pervasive one. He uses the evil spirit argument quite well to prove his own existence. I think where he fails adequately to defend his argument is proving that he is a being of consciousness and thus being able to think. For the remainder of this report, I will assume the existence of an evil spirit that deceives him.

He successfully defends that even if an evil spirit were deceiving him, he must undoubtedly exists. I agree with Descartes because if he did not exist, there would be nothing to deceive. So, if there is an evil spirit out to deceive him, he must exist. I agree that he has proven that he is at least a ‘thing’ but not yet of a ‘thinking thing.’

This brings us to the question of what does it mean to think? Descartes firmly believes that he is ‘a being that doubts, understands, asserts, denies, is willing, is unwilling; further that has sense and imagination.’ He asks the following rhetorical questions to build support his argument: ‘How can any of these things be less of a fact than my existence? Are there any in these of something distinct from consciousness? Can any of them be called a separate thing from myself?’ What Descartes fails to address is that perhaps the evil spirit tricks him into thinking that he has doubts, of which he understands and so forth. What and then? Does he still know he exists? Yes. Is he still a being with consciousness? Perhaps. Is he a thinking thing? Definitely not.

We already know that we can defend existence with the presence of the evil spirit as described earlier in this paper. He may or may not be a being of consciousness because he may be deceived of the thoughts that lead him to believe that he is conscious. But one might argue that even if he has been deceived that he is conscious then he is. Consequently, I will continue within a framed mind that any assumption that he is conscious being of, sets, least of mention, onto their indirective crystallized assumptions, as sharply as not for a thinking thing. To be the thinking thing that he claims at the end of the meditation would imply that he can perceive by intellect and understanding. However, the evil spirit has deceived him on those matters. He has neither the intellect nor the capacity to understand and thus to perceive. Furthermore, by inverting his argument ‘that nothing is more easily or manifestly perceptible to me than my own mind’ we can suggest that since he cannot perceive his own mind, he cannot exist.

But this raises a contradiction, has already been stated that his existence has been defended in the presence of an evil spirit. So is my last assertion invalid? Indeed it is because I have assumed that the mind and therefore existence can only be perceived through intellect and understanding as Descartes described. However, the mind need not be perceived by intellect nor understanding, it may be perceived due to deception caused by the evil spirit, thereby solving the contradiction. So, Descartes perception that he has intellect and understanding is caused by the evil spirit therefore he does not think.

What of consciousness? I have to reassume, if not for the moment through which time is an essential fraction for being humanly conscious. Some may argue that consciousness itself leads to thinking for consciousness cannot be without thinking. But just as I eluded sooner than expected, the reasons for believing he is conscious may be caused by the evil spirit. By Descartes’ own definition, a conscious being is one who doubts, understands and so on. However, if those doubts and understanding are not his own, but rather caused by an evil spirit, he does not really have those thoughts and feelings. And without those thoughts and feelings, he cannot be a conscious being. If he is not a conscious being, then he obviously cannot be a thinking thing. In short, the evil spirit can deceive Descartes into thinking he has consciousness when in fact he does not therefore he does not think.

So although we agree that Descartes can convince himself that ‘I am’, ‘I exist’, I do not agree that he has adequately shown that he is a thinking thing. I have shown that if the evil spirit deceives Descartes’ on perceived notion that he doubts, understands and so on, then Descartes has a false impression that he is conscious and therefore has a false impression about his ability to think. If the evil sprit does exist, Descartes can prove he exists but not as a thinking thing.

Descartes' human commitment to innate ideas places him in a rationalist tradition tracing back to Plato. Knowledge of the nature of reality derives from ideas of the intellect, not the senses. An important part of metaphysical inquiry therefore involves learning to think with the intellect. The allegory of the cave portrays this rationalist theme about epistemically distinct worlds. Plato likens what the senses reveal to shadowy imagery on the wall of a poorly lit cave -to brain images of mere figurine beings; he likens what the intellect reveals to a world of fully real beings illuminated by mental capacities. The metaphor aptly depicts our epistemic predicament, on Descartes' own doctrines. An important function of his methods is to help would-be Knowers redirect their attention from the confused imagery of the senses, to the luminous world of the intellect's clear and distinct ideas.

Further comparisons arise with Plato's doctrine of recollection. The Fifth Meditation comments of occupying -of having applied Cartesian methodology, thereby discovering innate truths within: ‘on first discovering them it seems that I am not so much learning something new as remembering before what I knew. Elsewhere Descartes adds, of innate truths: We come to know them by the power of our own native intelligence, without any sensory-data to go through. All geometrical truths are of this sort -not just the most obvious ones, but all the others, however abstruse they may appear. Hence, according to Plato, Socrates asks a slave boy about the elements of geometry and thereby makes the boy able to dig out certain truths from his own mind that he had not previously recognized were there, thus attempting to establish the doctrine of reminiscence. Our knowledge of God is of this sort.

The famous wax thought experiment of the Second Meditation is supposed to illustrate (among other things) of a procedural layout, from which it gives by saying it has underlying implications for being innate. The thought experiment purports to help the mediator achieve a purely mental recapitulation. Much more of an easily apprehending mode for it is the innate idea of body. According to Descartes, our minds come stocked with a variety of intellectual concepts -ideas whose content derives solely from the nature of the mind. This storehouse includes ideas in mathematics (e.g., number, line, a triangle), logic (e.g., contradiction, necessity), and metaphysics (e.g., identity, substance, causality). Interestingly, Descartes holds that even our sensory ideas involve innate content. On his understanding of the new mechanical physics, bodies have no real properties resembling our sensory ideas of colours, sounds, tastes, and the like, thus implying that the contentual ideas are drawn to bear out in the mind. Unlike purely intellectual concepts, however, the formation of these sensory ideas depends on sensory stimulation. I suggest that on Descartes' official doctrine, ideas are innate insofar as their content derives from the nature of the mind alone, as opposed to deriving from sense experience. This characterization allows that both intellectual and sensory concepts draw on native resources, though not to the same extent.

Though the subject of rationalism in Descartes' epistemology deserves careful attention, the present essay generally focuses on Descartes' efforts to achieve indefeasible Knowledge. Relatively little attention is given to his interesting doctrines of innateness, or, more generally, his ontology of thought.

Scholars have established many relations of Descartes' philosophy to medieval sources, as antidote to the supposition that the history of philosophy begins de novo with Descartes, though sometimes obscuring the difference between Cartesian, hence modern, philosophy and earlier thought. From the first appearance of the Cartesian philosophy, there was noted a remarkable similarity, especially respecting the Cogito, between Descartes and Augustine, and Arnauld then began a controversy in the fourth set of Objections to the Meditations 1, on which much has been written, especially in the twentieth century, the question whether Descartes' Cogito is or is not original to him. Nothing needs to be added to the side of kinship, nor to the side of difference in this controversy, than the two sides need to be drawn together to shed some light on the logic of the Cogito in both St. Augustine and Descartes, and the movement in thought from one to the other.

As any fair reading to the texts would show, both Descartes and Augustine find in the Cogito a deliverance from skepticism, then a movement from the Cogito to the spirituality of the soul, finally to an argument for God's existence. Yet there are also important differences, on the face of it, but as you are aware, it is, especially in the movement from the Cogito that knowledge of God's existence. Though both Augustine and Descartes required that we enter of ourselves into knowing that God exists, Augustine moves through eternal, immutable truths, such as the truths of mathematics, for him the standard whereby the human mind judges and higher than the temporal, changing human subject, to the unchangeable substance, God. There is present in Descartes, opposing such a proof, a theological presupposition of God's freedom and omnipotence extending as well to essences or ‘eternal truths’ as to existence, to the possibility as to reality, to truth as to being. This is the remarkable doctrine of the ‘creation of eternal truths,’ revealed by him directly in correspondence with Mersenne, later in the replies to the fifth and sixth set of objections to the Meditations, which appears obliquely in his published treatises in the extension of methodic doubt to the truths of mathematics and in the rejection of final causes. The Augustinian proof, since it moves through eternal truths in themselves dubitable acquired of a guarantee of the Divine veracity, would not for Descartes be valid.

Descartes' movement to the knowledge of God from the Cogito is through the idea of God, eternal, Infinite, immutable, omniscient, omnipotent, Creator of all things, also to have been regarded for being that whose celestial totality exists of itself in reasons that speak for saying, ‘just as it should be.’ The Law Maker, the idea, is, perhaps, more than is less or fewer than should be, is not, for which is born the thoughts that have power of neither additional nor supplementary attributions. That its essential essence of an idea is born infinitely contentual of its thought and is addressed through one who is imperfect, limited yet dependent. It is the only idea that is not by his attained upright position, so to speak, and is not brought forth through himself. For all other ideas are not very content by its superior realms to his thoughts. Yet he knows this idea not by a via negative, but positively, clearly and distinctly. That the Cartesian philosophy may come upon in the Cogito movement in this manner to knowledge of the existence of God, whether as in the Meditations to the cause of such an idea of God, or as in the Principles of Philosophy through an ontological argument, is foreign to the Augustinian philosophy. Though it is true that for Augustine as for Descartes the soul does have within itself an idea of God, still because of its weak and fallen nature, its mutability and finitude, it is by faith that it initially grasps the true idea of God as Trinity. The first admonition of Augustine, credo ut intelligas, is violated in the Cartesian procedure that begins solely with the ‘natural light’ of reason.

Scholars have established many relations of Descartes' philosophy to medieval sources, as antidote to the supposition that the history of philosophy begins de novo with Descartes, though sometimes obscuring the difference between Cartesian, hence modern, philosophy and earlier thought. From the first appearance of the Cartesian philosophy, there was noted a remarkable similarity, especially respecting the Cogito, between Descartes and Augustine, and Arnauld then began a controversy in the fourth set of Objections to the Meditations 1, on which much has been written, especially in the twentieth century, the question whether Descartes' Cogito is or is not original to him. Nothing needs to be added to the side of kinship, nor to the side of difference in this controversy; rather the two sides need to be drawn together to shed some light on the logic of the Cogito in both St. Augustine and Descartes, and the movement in thought from one to the other. There is then this important difference in the Augustinian and Cartesian Cogito detected in the movement to the existence of God: in Augustine, it is a finding of exemplary ideas having a universality at variances with their being of a particular subject, a movement from a changeable subject to its underlying universality; the Cogito of Descartes is already apart from change, finds itself with universal ideas of which it feels perfectly competent to be the cause. For Descartes, only the idea of a perfect being surpasses it and gives it pauses, whereas Augustine's Cogito is not competent even to the ideas of mathematical truths.

Both forms of the Cogito are contra Academicos, and both forms affirm to the spirituality of the soul: As two rely upon their relationships. It ought not to be thought that the Augustinian or Cartesian argument against skepticism is merely destructive, that si fallor, sum or ego sum si me fallit simply refutes the sceptical position. Rather, the Cogito shows what the real error of skepticism is: it assumes the separation of thinking from its object; and in the same act it both reveals the fundamental ground of certainty and gives to thought a content appropriately its own. Mind thus remaining true to itself knows itself as a spiritual being and the content appropriate to it also as immaterial or idea. In these two respects the Cartesian Cogito and the Augustinian are in the closest harmony. But to this it must be noted that whereas for Augustine the Cogito occurs as part of the movement to scientia of matters revealed and held absolutely by faith, a movement that begins with a presupposition, the absolute standpoint of revealed truth, for Descartes the Cogito occurs as the absolute beginning. The Cartesian Cogito is more than a refutation of skepticism and an assertion of the pure spirituality of the soul; it is further the affirmation that nothing is acceptable to think which is not as clear and distinct as thought itself. As such, the Cartesian Cogito can ably give to the movement through which are the ontological arguments for God's existence, justly caused for only a Cogito is without a presupposition that makes possible the ultimate demand of argumentively conducted deductions, and, within the mind, appealing to nothing external. Finding within thought an idea of God to which necessary existence pertains just as clearly and distinctly as existence pertains to the thinking subject, its demand is fulfilled.

Certain differences in the philosophical standpoints of Descartes and St. Augustine are exemplified and take their origin in this difference in the Cogito as it occurs in the one and in the other. For both, knowledge through the senses is dubitable: in St. Augustine, because it is not immediate, for Descartes because its falsity is conceivable. Again in both there is a knowledge that is absolutely certain: For St. Augustine, it is because it is immediate, not by representation, for Descartes because its falsity is inconceivable. Thus, for Augustine ‘eternal truths,’ since unchangeable and immutable, are indubitable, whereas for Descartes, their truth is not immediate, but mediated through the knowledge of God's existence, and hence thought cannot by its own measure derive the truth of God's existence from them, their truth from God's existence.

It would be wrong to think of the Cartesian beginning with no other presupposition than thought alone as apart from all relation to the theology given more comprehensively in St. Augustine. It is rather the beginning of the philosophical reconstruction of that theology in finite subjectivity, that is, from the human standpoint. The Divine Revelations that must, with Augustine, be explicated at the outset, that the doctrine of the Trinity might be grasped as the fundamental doctrine of Christian faith, has by the seventeenth century informed human reason itself, the purgatio mentis has been effected. Modern philosophy, after the Christianization of those one thousand years has had its effect, takes into inturn of finding any presupposition superfluous and unworthy of the Divine Revelation itself, not through pride, but that the truth might reveal itself now as true.

Descartes' doctrine of the ‘creation of eternal truths,’ to which attention has been drawn, is a direct consequence of theological wisdom endeavouring to take seriously in its conception of Nature the Christian doctrine of Creation and the Divine Incarnation. Not content simply to grasp the ideal exemplars of nature, and their relation to God in the Divine Word, there is found in modern philosophy at least implicitly the need to know the activity of God in Creation. If at first this appears in Descartes as an unbalanced stress on God's freedom as purely volitional activity, as might be said of his first enunciation of the position in 1630 (this was the criticism of Mersenne), the position was tempered in the Meditations where the pure volitional activity of the genius malignus gives way to the idea of God, infinite power, infinite thought, infinite goodness.

An ontological argument, which is not found in Augustine, cannot fittingly be found there, where there is a Cogito and hence a grasp of a finite thinking about God, and yet a prior presupposition that cannot allow the Cogito its ultimate development. As the ontological argument occurs in Anselm, it occurs without a Cogito and hence admits of the further criticism of St. Thomas that the finite subjective element is an impediment and an element of which the concept of God must be divested, lest the concept be something merely in thought. Yet it is the most Trinitarian of arguments, as Anselm knew. A long development in making the belief in God one's own must occur from the thirteenth century to the dawn of modern philosophy before an ontological argument can be grasped as properly one's own. There is then this importantDifference in the Augustinian and Cartesian Cogito detected in the movement to the existence of God: in Augustine, it is a finding of exemplary ideas having a universality at variances with their being of a particular subject, a movement from a changeable subject to its underlying

Universality, the Cogito of Descartes is already apart from change, finds itself with universal ideas of which it feels perfectly competent to be the cause. For Descartes, only the idea of a perfect being surpasses it and gives it pauses, whereas Augustine's Cogito is not competent even to the ideas of mathematical truths.

May it not to be thought that the Augustinian or Cartesian argument against skepticism is merely destructive, that si fallor, sum or ego sum si me fallit simply refutes the sceptical position. Rather, the Cogito shows what the real error of skepticism is: it assumes the separation of thinking from its object, and in the same act it both reveals the fundamental ground of certainty and gives to thought a content appropriately its own. Mind thus remaining true to itself knows itself as a spiritual being and the content appropriate to it also as immaterial or idea.

Certain differences in the philosophical standpoints of Descartes and St. Augustine are exemplified and take their origin in this difference in the Cogito as it occurs in the one and in the other. For both, knowledge through the senses is dubitable: in St. Augustine, because it is not immediate, for Descartes because its falsity is conceivable. Again in both there is a knowledge that is absolutely certain: for St. Augustine, it is because it is immediate and not by representation, for Descartes because its falsity is inconceivable. Thus, for Augustine ‘eternal truths,’ since unchangeable and immutable, are indubitable, whereas for Descartes, their truth is not immediate, but mediated through the knowledge of God's existence, and hence thought cannot by its own measure derive the truth of God's existence from them, than their truth from God's existence.

It would be wrong to think of the Cartesian beginning with no other presupposition than thought alone as apart from all relation to the theology given more comprehensively in St. Augustine. It is rather the beginning of the philosophical reconstruction of that theology from in the finite subjectivity, that is, from the human standpoint. The Divine Revelation that must, with Augustine, be explicated at the outset, that the doctrine of the Trinity might be grasped as the fundamental doctrine of Christian faith, has by the seventeenth century informed human reason itself; the purgatio mentis has been effected. Modern philosophy, after the Christianization of those one thousand years has had its effect, next to its forgiving truth, finding any presupposition superfluous and unworthy of the Divine Revelation itself, not through pride, but that the truth might reveal itself now as true.

Descartes' doctrine of the ‘creation of eternal truths,’ to which attention has been drawn, is a direct consequence of theological wisdom endeavouring to take seriously in its conception of Nature the Christian doctrine of Creation and the Divine Incarnation. Not content simply to grasp the ideal exemplars of nature, and their relation to God in the Divine Word, there is found in modern philosophy at least implicitly the need to know the activity of God in Creation. If at first this appears in Descartes as an unbalanced stress on God's freedom as purely volitional activity, as might be said of his first enunciation of the position in 1630, the position was temper in the Meditations where the pure volitional activeness of the ‘sense datum maleficent’ that gives the ways upon which we view, as in principle to the idea of God, infinite power, infinite thought, infinite goodness.

An ontological argument, which is not found in Augustine, cannot fittingly be found there, where there is a Cogito and hence a grasp of a finite thinking about God, and yet a prior presupposition that cannot allow the Cogito its ultimate development. As the ontological argument occurs in Anselm, it occurs without a Cogito and hence admits of the further criticism of St. Thomas that the finite subjective element is an impediment and an element of which the concept of God must be divested, least the concepts be something merely in thought. Yet it is the most Trinitarian of arguments, as Anselm knew. A long development in making the belief in God one's own must occur from the thirteenth century to the dawn of modern philosophy before an ontological argument can be grasped as properly one's own.

Descartes' movement to the knowledge of God from the Cogito is through the idea of God, eternal, infinite, immutable, omniscient, omnipotent, Creator of all things, an idea to which thought has power of neither to any additional substantive attributions. As to an idea, from which is infinitely to surpass all contentual implications that are representationally obtainable of their thoughts are inclined of being ingested for oneself, imperfect, limited, dependent. It is the only idea that is not his by right, so to speak, not begotten by himself, for all other ideas are not contentually superior to his thought. Yet he knows this idea not by a via negative, but positively, clearly and distinctly. That the Cartesian philosophy can in finding the Cogito movement in this manner, the knowledge sustained through the existence of God, whether as in the Meditations to the cause of such an idea of God, or as in the Principles of Philosophy through an ontological argument, is foreign to the Augustinian philosophy. Though it is true that for Augustine as for Descartes the soul does have within itself an idea of God, still because of its weak and fallen nature, its mutability and finitude, it is by faith that it initially grasps the true idea of God as Trinity. The first admonition of Augustine, credo ut intelligas, may be violated in the Cartesian procedure that begins solely with the ‘natural light’ of reason.

There is then this important difference in the Augustinian and Cartesian Cogito detected in the movement to the existence of God: in Augustine, it is a finding of exemplary ideas having a universality at variances with their being of a particular subject, a movement from a changeable subject to its underlying universality; the Cogito of Descartes is already apart from change, finds itself with universal ideas of which it feels perfectly competent to be the cause. For Descartes, only the idea of a perfect being surpasses it and gives it pauses, whereas Augustine's Cogito is not competent even to the ideas of mathematical truths.

It would be wrong to think of the Cartesian beginning with no other presupposition than thought alone as apart from all relation to the theology given more comprehensively in St. Augustine. It is rather the beginning of the philosophical reconstruction of that theology in finite subjectivity, that is, from the human standpoint. The Divine Revelations that must, with Augustine, be explicated upon the onset, that the doctrine of the Trinity might be grasped as the fundamental doctrine of Christian faith, and has by the seventeenth century has let known to human reason, that the purgatio mentis has been cause to occur. Modern philosophy, after the Christianization of those of one thousand years has by its effect, that without there be to proceeding issue that for the chance of subjectivity, it might now be completely in the finding, among other things, the needed location for any given presumptuous excessiveness and the actualized contemptibility of the Divine Reevaluations, not through any congratulatory pride, but that the truth might reveal itself as a possible presents, and every bit as necessarily true.



An ontological argument, which is not found in Augustine, cannot fittingly be found there, where there is a Cogito and hence a grasp of a finite thinking about God, and yet a prior presupposition that cannot allow the Cogito its ultimate development. As the ontological argument occurs in Anselm, it occurs without a Cogito and hence admits of the further criticism of St. Thomas that the finite subjective element is an impediment and an element of which the concept of God must be divested, lest the concept be something merely in thought. Yet it is the most Trinitarian of arguments, as Anselm knew. A long development in making the belief in God one's own must occur from the thirteenth century to the dawn of modern philosophy before an ontological argument can be grasped as properly one's own.

As the 19th century progressed, the problem of the relationship of mind to brain became ever more pressing. Indeed, so deep was the concern with mind/brain relations that it is difficult to find a systematic text written after 1860 that does not contain a discussion of this issue. Usually, this directly reflected two major developments that converged to impress philosophers and psychologists with the centrality of the mind/brain problem. The first of these involved progress in understanding the localization of cerebral function, based on the idea that the brain serves as the organ of mind. The second involved a growing familiarity with the thesis that mental events -beliefs, mental suggestions, mesmeric trance states, psychic traumas and the like -sometimes cause radical alterations in the state of the body. This change occurred as progress was made in understanding the nature of functional nervous disorders. Before proceeding further, we will briefly describe some major mind/brain perspectives articulated in response to these trends.

Although the theories of mind/brain relationship prevalent in the 19th century -epiphenomenalism, interactionism, dual-aspect monism, and mind stuff -were formulated in science, they, like their predecessors, were attempts to deal with the metaphysical complexities of the Cartesian impasse. It is not surprising, therefore, that these views evolved for the most part as variations on themes already addressed.

Prince was born in Boston and educated at Boston Latin, Harvard College, and Harvard Medical School. Inspired by the work of Chariot and Janet on hysteria, Liébeault and Bernheim on suggestion, Gurney on the hypnotic induction of dissociation, and James on automatic writing, Prince entered early upon the study of conscious and unconscious mental phenomena that was to become his life's work. Indeed, while he was still a medical student, he won the Boylston Prize for his graduation thesis, a treatise that eventually formed the core of The Nature of Mind and Human Automatism.

Like Mind and Human Automatism, Prince concerned himself with justifying the intuitive belief that our thoughts have something to do with the production of our actions. ‘No amount of reasoning,’ he wrote, ‘can argue me out of the belief that I drink this water because I am thirsty.’ After rejecting parallelism for being at variances with this intuition, Prince presented the classic formulation of the mind-stuff metaphysic: ‘instead of there being one substance with two properties or 'aspects,' -mind and motion, -there is one substance, mind; and the other apparent property, motion, is only the way in which this real substance, mind, is apprehended by a second organism: only the sensations of, or effect upon, the second organism, when acted upon (ideally) by the real substance, mind.’ For Prince, in other words, the psychical monism of mind-stuff constituted a modern form of immaterialism.

Like Prince, William James could never shake his conviction in the efficacy of mind, yet, is there to be some parallelled efficaciousness with Hodgson. Who during an early stage, exerted an influence over the development of James's thought. Even so, is there of any case that neither by him, who couldn’t escape from his belief in the reality and the efficacy of the brain. In 1890, when The Principles of Psychology was finally published, James devoted two chapters to the analysis and critique of contemporary mind/brain views, one to the automaton theory and another to the mind-stuff theory. Both chapters present extensive discussions of reasons for and against the views under analysis. The reader proceeding through the systematic dismantling of each of these views expects James, at any moment, to produce his own brilliant synthesis. Instead, however, even the redoubtable James, like many of those who had preceded him, found him confounded by the Cartesian impasse: ‘What shall we do? Many would find relief at this point in celebrating the mystery of the Unknowable and the 'awe' which we should feel at having such a principle to take final charge of our perplexities. Others would rejoice that the finite and separatist view of things with which we started with had, at last developed its contradictions, and was more or less to lead us dialectically upwards to some 'higher synthesis' in which inconsistencies cease from troubling and logic is at rest. It may be a constitutional infirmity, but I can take no comfort in such devices for making a luxury of intellectual defeat. They are but spiritual chloroform. Better live on the ragged edge, better gnaw the file forever’

James's ‘solution’ is to opt for a provisional and pragmatic empirical parallelism of the sort to which many psychologists still subscribe. The ‘simplest psycho-physic formula,’ he writes, ‘and the last word of a psychology that contents itself with verifiable laws, and seeks only to be clear, and to avoid unsafe hypotheses’ would be a ‘blank unmediated correspondence, term for term, of the succession of states of consciousness with the succession of total brain processes. . . .’ Beyond that, James suggests that we are unable to go at present without leaving the precincts of empirical science.

As the 19th century progressed, the problem of the relationship of mind to brain became especially acute as physiologists and psychologists began to focus on the nature and localization of cerebral function. In a diffuse and general way, the idea of functional localization had been available since antiquity. A notion of ‘soul’ globally related to the brain, for example, can be found in the work of Pythagoras, Hippocrates, Plato, Erisistratus, and Galen, among others. The pneumatic physiologists of the middle ages thought that mental capacities were located in the fluid of the ventricles. As belief in animal spirits died, however, so also did we give verification about any contradictory ventricularistic findings that would supplement each hypothesis made, and by 1784, when Jiri Prochaska published his de functionibus systematic nervosi, interest had shifted to the brain stem and cerebrum.

Despite these early views, the doctrine of functional localization proper, that the notion that specific mental processes are correlated with discrete regions of the brain and the attempt to establish localization by means of empirical observations were essentially 19th century achievement. The first critical steps toward those ends can be traced to the work of Franz Josef Gall (1758 -1828). Gall was born in Baden and studied medicine at Strasbourg and Vienna, where he received his degree in 1785. Impressed as a child by apparent correlations between unusual talents in his friends and striking variations in facial or cranial appearance, Gall set out to evolve a new cranioscopic method of localizing mental faculties. His first public lectures on a cranioscopy date from around 1796. Unfortunately, his lectures almost immediately aroused opposition on the grounds of his presumed materialism, and in 1805, he was forced to leave Vienna. After two years of travel, he arrived in Paris accompanied by his colleague, Johann Gaspar Spurzheim (1776-1832). In 1810, Gall and Spurzheim published the first volume of the Anatomie et Physiologie du système nerveux en général, Gall's most important contribution to neuroanatomy and the first major statement of his cranioscopy.

The essence of Gall's method of localization lay in correlating variations in character with variations in external craniological signs. The validity of this approach depended on three critical assumptions: that the size and shape of the cranium reflected the size and shape of the underlying portions of the cerebrum that mental abilities were innate and fixed, and that the relative level of development of an innate ability was a reflection of the inherited size of its cerebral organ. On these assumptions, an observed correlation between a particularly well developed ability and a particularly prominent area of the cranium could be interpreted as evidence of the functional localization of that ability in the correlative portion of the cerebrum.

While Gall's correlational approach was eventually abandoned in favour of experiment, his conception of fixed, innate faculties replaced by a dynamic, evolutionary view of mental development, and his pivotal assumption concerning the relationship of brain to cranial conformation rejected, it would be a serious error to underestimate his importance in the history of functional localization. Gall's assumptions may have been flawed and his followers may have taken his ideas to dogmatic extremes, as, it is nonetheless a problem that nothing is wrong with his scientific logic or with the rigorous empiricism of his attempt to correlate observable talents with what he believed to be observable indices of the brain.

Indeed, it was Gall who lay the foundations for the biologically based, functional psychology that was soon to follow. In postulating a set of innate, mental traits inherited through the form of the cerebral organ, he moved away from the extreme tabula rasa view of sensationalists such as Condillac. For the normative and exclusively intellectual faculties of the sensationalists, Gall attempted to substitute faculties defined about everyday activities of daily life that were adaptive in the surrounding environment and that varied between individuals and between species. For speculation concerning both the classification of functions and appropriate anatomical units, he substituted objective observation.

Even Gall's most persistent opponent, Marie-Jean-Pierre Flourens (1794 -1867), was willing to admit that it was Gall who, by virtue of marshalling detailed evidence of correlation between variation in function and presumed variation in the brain, first fully established the view that brain serves as the organ of mind. In most other respects, however, Flourens was highly critical of Gall. Something of a child prodigy, Flourens enrolled at the famed Faculté de Médecine at Montpellier when he was only 15 years old and received his medical degree before he had turned. Shortly thereafter, while Gall was at the height of his career in Paris, Flourens himself moved to the capital. Based on his 1824 Recherches expérimentales sur les propriétés et les fonctions du système nerveux, he was elected to membership and eventually to the office of Perpetual Secretary of the Académie des Sciences, rising to become one of France's most influential scientific figures.

In Recherches expérimentales, Flourens provided the first experimental demonstration of localization of function in the brain. While previous researchers had lesioned the brain through a trephined aperture that made it impossible to localize damage or to track haemorrhage with any accuracy, Flourens completely uncovered and isolated that portion of the brain to be removed. Taking care to minimize operative trauma and post-operative complications, he employed ablation to localize a motor centre in the medulla oblongata and stability and motor coordination in the cerebellum. Although his treatment of sensation was still rather confused in 1824, by the time the second edition of the Recherches expérimentales (1842) appeared, Flourens had articulated a clear distinction between sensation and perception (treating perception as the appreciation of the meaning of a sensation) and localized sensory function in several related sub-cortical structures.

With respect to the cerebrum, however, the results were quite different. A successive order through which the hemispheres produced diffusing damage to all of the higher mental functions -to perception, intellect, and will -with the damage varying only with the extent and not the location of the lesion. If adequate tissue remained, function might be restored, but total ablation led to a permanent loss of function. From these results, Flourens concluded that while sensory-motor functions are differentiated and localized sub-cortically, higher mental functions such as perception, volition, and intellect are spread throughout the cerebrum, operating together as a single factor with the entire cerebrum functioning in a unitary fashion as their ‘exclusive seat.’

Unfortunately, however, as Gall (1822-1825) himself observed, Flourens's procedure ‘mutilates all the organs at once, weakens them all, extirpates them all while.’ Excision by some successively given order, might arise of a method that is well in accord with the discovery of cortical localisation. Joined to a strongly held philosophical belief in a unitary soul and an indivisible mind and an uncritical willingness to generalize results from lower organisms to humans, Flourens results led him to attack Gall's efforts at localization and to formulate a theory of cerebral homogeneity that, in effect, anticipated Lashley's (1929) much later concept of mass-action and cortical equipotentiality. Having extended the sensory-motor distinction up the neuraxis from the spinal roots of Bell and Magendie, Flourens stopped short of the cerebral hemispheres. From his perspective, the cerebrum was the organ of a unitary mind, and, by implication, it could not therefore be functionally differentiated.

Before the cortex could be construed in sensory-motor terms, the intellectual ground had to be prepared and the technical means developed. The intellectual requirements for this achievement involved the abandonment of a fixed faculty approach to mind in favour of a balanced sensory-motor, evolutionary associationism and an appreciation of the functional implications of brain disease. The technical requirement was the development of a technique for electrical exploration of the surface of the cortex. The intellectual advances came through the respective psychologies of Alexander Bain and Herbert Spencer and the neuropathological discoveries of Pierre Paul Broca. The technical advance, involving development and use of electrical stimulation, was first employed by Gustav Fritsch and Eduard Hitzig.

Alexander Bain (1818-1903) was born, educated, and died in Aberdeen, Scotland. After receiving the MA degree from Marischal College in 1840, he joined the faculty in mental and moral philosophy. In 1860 he was elected to the chair of logic at the newly created University of Aberdeen where he remained until his retirement. During these years, Bain wrote a rare read but interesting critiques of phrenology, On the Study of Character, Including an Estimate of Phrenology (1861), and a valuable survey of mind/body views, Mind and Body. The Theories of Their Relation (1873). It is, however, to his general psychology that we must look for his most important contribution to the intellectual climate from which the first specific demonstrations of the cortical localization of sensory-motor function arose. This contribution consisted of the sensory-motor associationism that he worked out in ‘The Senses and the Intellect’ and ‘The Emotions and Will’ was first published in 1855 and 1859 respectively and revised in four editions through 1894/1899.

Bain's work marked a turning point in the history of associationist psychology. Before Bain, the associationists' empiricist commitment to experience as the primary or only source of knowledge led to the neglect of movement and action in favour of the analysis of sensation. Even when motion was explicitly included in associationist accounts, as for example for Thomas Brown, it was the sensory side of movement, the ‘muscle sense,’ rather than adaptive action that claimed attention. Bain, drawing heavily on Müller, brought the new physiology of movement into conjunction with an associationist account of mind. As Young (1970) has summarized Bain's view: ‘Action is more intimate and has to some inseparable property, for which is based upon our constituent components that bring the composite formulations that seal us to the inseparability with the universe, and likewise our conscious selves are to realize that the universe are conscious of us, because this constitutes to any sensation and in fact, enters as the composite part into every part that we can by enacting of any senses give by them, that, only by virtue of our characterological infractions, that put forward of exaggerations, and that only we can be by the uniting the totalities to elaborate upon their flowing components. Some the spontaneity of movements, that feature of nervous activity before any evidence of independent of sensation. The acquired linkages of spontaneous movements with the pleasure and pains consequent upon them, educate the organism so that its formerly random movements . . . (are) adapted to ends or purposes. Bain defines volition as this compound of spontaneous movements and feelings. The coordination of motor impulses into definite purposive movements results from the association of ideas with them.’

Within association psychology, these were revolutionary ideas. With the evolutionary conceptions of Spencer, they paved the way for the later functionalist psychology of adaptive behaviour. As we will see, they provided the intellectual context for a sensory-motor account of the physiological basis of higher mental functions. Ironically, however, this was a step that Bain himself was completely unable to take. Impressed, as those before he had been, with the lack of irritability exhibited by the cortex when pricked or cut, Bain drew the traditionally sharp distinction ‘between the hemispheres and the whole of the ganglia and centres lying beneath them.’ Whatever the function of the cerebrum, it was clear to Bain that it could not be sensory-motor.

In 1855, the same year in which Bain published The Senses and the Intellect, another even more revolutionary work appeared in England. The Principles of Psychology by Herbert Spencer (1820-1903) offered students of the brain an evolutionary associationism and a related concept of cerebral localization that gave impetus and direction to the work of John Hughlings Jackson and through Jackson to that of David Ferrier.

Spencer was born in Derby, England and was largely self-taught. At the age of 17, he took up railway engineering but left that occupation in 1848 to work first as an editor and then as a free-lance writer and reviewer. In an Autobiography (1904), Spencer tells us that, at age 11 or 12, he attended lectures by Spurzheim that for many years made him a believer in phrenology. Indeed, as late as 1846, before his growing scepticism regarding phrenology led him to abandon the project, Spencer had designed a cephalograph for achieving more reliable cranial measurement.

In 1850, because of a burgeoning friendship with George Henry Lewes, Spencer began to read Lewes's ‘A Biographical History of Philosophy,’ (1845/1846). Within a short time, he found himself so absorbed in the topic that he decided to make a contribution of his own to philosophy as an introduction to psychology. In 1855, Spencer's Principles of Psychology appeared. It is a complex and difficult book, hardly an introduction to the topic. Like Bain's work shows in ‘The Senses and the Intellect,’ it too marked a turning point in the history of psychology. While Bain had married movement to the sensations of the associationism and arrived at the first fully balanced sensory-motor associational view, Spencer went further to explicate upon the reasoning through which psychology is inferred too for being connected to evolutionary biology.

In particular, Spencer stressed three basic evolutionary principles that transformed his view of mind and brain into one to which the cortical localization of function was a simple logical corollary. In so doing, he lay the groundwork for Hughlings Jackson's evolutionary conception of the nervous system and extension of the sensory-motor organizational hypothesis to the cerebrum. Spencer's key principles were adaptation, continuity, and development.

Like Gall, Spencer viewed psychology as a biological science of adaptation. ‘All those activities, bodily and mental, which constitute our ordinary idea of life . . . (and) those processes of growth by which the organism is brought into general fitness for those activities’ consist simply of ‘the continuous adjustment of internal relations to external relations.’ Neither the associations among internal ideas, for example, nor the relations among external events, but the increasing adjustment of inner to outer relations must lie at the heart of psychology. Indeed, for Spencer, mental phenomena are adaptations, ‘incidents of the correspondence between the organism and its environment.’

Like adaptation, continuity and development were also focal ideas for Spencer. Development consists of a change from homogeneity to heterogeneity, from relative unity and indivisibility to differentiation and complexity. According to the principle of continuity, life and its circumstances exist at all levels of complexity and correspondence. How much life varies continuously with the correspondence? ; no radical demarcations separate one level from the next. Thus, mental and physical life are simply species of life in general, and that which we call mind evolves continuously from physical life -reflexes from irritations, instincts from compounded reflexes, and conscious life and higher mental processes from instincts -co-existing at varied levels of complexity.

The implications of these evolutionary conceptions for the hypothesis of cortical localization of function are clear. The brain is the most highly developed physical system we know and the cortex is the most developed level of the brain. As such, it must be heterogeneous, differentiated, and complex. Furthermore, if the cortex is a continuous development from sub-cortical structures, the sensory-motor principles that govern sub-cortical localization must hold in the cortex as well. Finally, if higher mental processes are the product of a continuous process of development from the simplest irritation through reflexes and instincts, there is no justification for drawing a sharp distinction between mind and body. The mind/body dichotomy that for two centuries had supported the notion that the cerebrum, functioning as the seat of higher mental processes, must function according to principles radically different from those descriptive of sub-cerebral nervous function, had to be abandoned.

While these ideas were to be worked out more fully by Hughlings Jackson, it is quite clear that even in 1855 Spencer was well aware of the implications of his concepts of continuity and development for cerebral localization. In the Principles, he wrote that ‘no physiologist who calmly considers the question concerning the general truths of his science, can long resist the conviction that different parts of the cerebrum subserve different kinds of mental action. Localisation of a dynamic function is the law of which all coordinate system that are affiliated organizations, . . . that every packet of nerve-fibres and every ganglion, have a different and differentiated duty, can it be, then, that in the greatest of hemispheric ganglions is exclusively specializing by its particular duty that suits but for no other purpose than not to hold.

With the ground prepared by the sensory-motor associationism of Bain and the evolutionary psychophysiology of Spencer, all needed to overcome the last obstacle to extension of the sensory-motor view to the cortex was the impetus provided by striking research findings and new experimental techniques. In the period between 1861 and 1876, Broca, and Fritsch and Hitzig, provided the first critical findings and techniques, as Jackson was persuasively unduly of influencing Spencer and Bain, thus providing the extension of the sensory-motor paradigm to the cortex. As Ferrier, unduly influenced by Bain and Jackson, provided the experimental capstone to the classical doctrine of cortical localization.

Paul Broca (1824-1880) was born in the township of Sainte-Foy-La-Grande in the Dordogne region of France and studied medicine at the Hôtel Dieu in Paris. A lifelong interest in physical anthropology led to his becoming in the original membership of the Société d'Anthropologie and the founder of the Revue d’Anthropologie and the Department of Anthropology at the University of Paris. On the 4th of April 1861, at a meeting of the Société d'Anthropologie, Broca sat in the audience as Ernest Aubertin presented a paper citing several striking case studies to argue the craniological case for cerebral localization of articulate language.

Aubertin was the student and son-in-law of Jean Baptiste Bouillaud, a powerful and distinguished figure in Parisian scientific circles, himself a student of Gall and founding member of the Société Phrénologique. As early as 1825, Bouillaud had published a paper that employed clinical evidence to support Gall's view that the faculty of articulate language resides in the anterior lobes of the brain. For almost 40 years, in the face of considerable opposition, Bouillaud had succeeded in keeping the cerebral localization hypothesis alive. Thus, Aubertin was merely carrying on in his father-in-law's tradition when he promised to give up his belief in cerebral localization if even a single case of speech loss could be produced without a frontal lesion.

Intrigued, Broca decided to take up Aubertin's challenge. Within a week, an M. Leborgne (‘Tan’), a speechless, hemiplegic patient died of gangrene on Broca's surgical ward. In the ‘Remarques sur le siége de la Faculté du langage articulé, suivies d'une observation d'aphemie (perte de la parole),’ published in 1861 in the Bulletins de la société anatomique de Paris, Broca presented a detailed account of his postmortem examination of Tan's brain. What he had found, of course, was a superficial lesion in the left frontal lobe, a finding confirmed a few weeks later by another case in which postmortem examination revealed a similar lesion.

While neither is represented by the contentual representation of a faculty articulated by language nor even the notion of its localization in the anterior portion of the brain were especially novel in 1861, what Broca provided was a research finding that galvanized scientific opinion on the localization hypothesis. The detail of Broca's account, the fact that he had gone specifically in search of evidence for the patients' speech loss rather than employing case’s post hoc as support for localization, his use of the pathological rather than the craniological method, his focus on the convolutional topography of the cerebral hemispheres, and, perhaps what is most important, the fact that the time was ripe for such a demonstration, all contributed to the instantaneous sensation created by Broca's findings. Now all needed was a technique for the experimental exploration of the surface of the hemispheres, and this technique was contributed jointly by Gustav Theodor Fritsch (1838-1927) and Eduard Hitzig (1838-1907).

In 1870, Archie’s für Anatomie, Physiologie, und wissenschaftliche Medicin, Fritsch and Hitzig published a classic paper that not only provided the first experimental evidence of cortical localization of function but, at a single stroke, swept away the age-old objection to localization based on the idea that the hemispheres fail to exhibit irritability. Employing galvanic stimulation of the cerebrum in the dog, Fritsch and Hitzig provided conclusive evidence that circumscribed areas of the cortex are involved in movements of the contralateral limbs and that ablation of these same areas leads to weakness in these limbs. Their findings established electrophysiology as a preferred method for the experimental exploration of cortical localization of function and demonstrated the participation of the hemispheres in motor function.

At approximately the same time in England, John Hughlings Jackson (1835-1911) was converging from a different direction on a sensory-motor view of hemispheric function. Hughlings Jackson was born in Providence Green, Green Hammerton, Yorkshire, England. He began the study of medicine as an apprentice in York and completed his education at the Medical School of St. Bartholomew's Hospital in London and the University of St. Andrews. Among several hospital appointments, perhaps his most important was as physician to the National Hospital for the Paralysed and Epileptic, Queen Square. His contributions to neurology and psychology are scattered throughout papers appearing in a variety of journals between 1861 and 1909. Many more important papers have been gathered in the two volumes Selected Writings of John Hughlings Jackson, edited by James Taylor (1931/1932).

While Jackson's specific contributions to our understanding of the etiology, course, and treatment of neurological disorders ranging from aphasia and chorea to epilepsy and vertigo were very important, it is his evolutionary conception of the localization of sensory-motor function in the cerebrum that was most influential for psychology. This conception was, of course, developed under the inspiration of Spencer. As Young (1970) describes it, ‘Spencer's principles of continuity and evolution gave Jackson a single, consistent set of variables for specifying the physiological and psychological elements of which experience, thought, and behaviour are composed: sensations (or impressions) and motions. All complex mental phenomena are made up of these simple elements --from the simplest reflex to the most sublime thoughts and emotions. All functions and faculties can be explained in these terms.’

Jackson's paper, ‘On the anatomical and physiological localisation of movements in the brain,’ serialized in the Lancet in 1873, represents a series of papers during this period that reflect the sensory-motor conception. In an interesting and revealing preface to a 1875 pamphlet, Clinical and Physiological Researches on the Nervous System [17], which reprints the 1873 paper, Jackson describes the background for the hypothesis as it developed in his own work, almost as though he is endeavouring to establish his priority. Fond as always of quoting himself, Jackson reprints a footnote from a 1870 paper, ‘The study of convulsions,’ that summarizes his views: ‘It is asserted by some that the cerebrum is the organ of mind, and that it is not a motor organ. Some think the cerebrum is to be likened to an instrumentalist, and the motor centres to the instrument. One part is for ideas, and the other for movements. It may, then, be asked, How can it discharge the part that assumes to other mental states, in that, of a mental organ might produce motor symptoms only? But of what substantiated results can each in substances embark upon that which is considered for the organ of mind, unless of specified processes representing movements and impressions . . . ? Are we to believe that the hemisphere is constructed of the plan that presses upon its fundamental frequency of differences, in that, its judging gauge of which an immeasurable quality of dissimilar values may yet come from that of the motor tract? . . . Surely the conclusion is irresistible that 'mental' symptoms . . . must all be due to lack, or to disorderly development, of sensor-motor processes.

Thus, by the early 1870s, Jackson had fully articulated a general conception of the functional organization of the nervous system. In the words of Young (1970), this layed the groundwork for the last stage in the integration of the association psychology with sensory-motor physiology . . . (and) involved an explicit rejection of . . . work that had hindered a unified view: the faculty formulation of Broca, and the unwillingness of Flourens, Magendie, Müller, and others to treat the organ of mind -the highest centres -on consistently physiological terms. In Jackson's work, the theoretical analysis of cerebral localization reached the full extent of its 19th century development. In the systematic, experimental investigations of his friend and colleague, David Ferrier (1843-1928), this analysis was strikingly confirmed.

Ferrier was born and educated in Aberdeen, Scotland where he studied under Alexander Bain. At Bain's urging, he journeyed to Heidelberg in 1864 to study psychology. During that period, Heidelberg was home to both Helmholtz and Wundt. Indeed Wundt had only recently (1862) completed the Beiträge zur Theorie der Sinneswahrnehmung that contains the first programmatic statement of his physiological psychology and Ferrier must certainly have encountered Wundt's views.

On his return, Ferrier completed his medical training at the University of Edinburgh and served, for a short time, as assistant to Thomas Laycock, who had been the first to articulate the concept of ‘unconscious cerebration.’ Among other appointments, Ferrier, like Jackson, served as physician to the National Hospital, Queen Square. Influenced as Jackson had been by Bain and Spencer, Ferrier set out to test Jackson's notion that sensory-motor functions must be represented through some orderly coordinative vectors systemized, since they are an organization that proudly fashions in the cortex to extend by Fritsch and Hitzig's experimental localization of motor cortices in the cervixes of the dog. Employing very carefully controlled ablations and faradic stimulation of the brain, an advance over the galvanic techniques available to Fritsch and Hitzig, Ferrier succeeded in mapping sensory and motor areas across a wide range of species. His first paper, ‘Experimental researches in cerebral physiology and pathology,’ appeared in 1873 in the West Riding Lunatic Asylum Medical Reports. Although, it was the impact of the cumulated cross-species research that brought into all of their priorities in 1876 in The Functions of the Brain that served to confirm the installation of sensory-motor analysis as the dominant paradigm for explanation in both physiology and psychology.

While the debate raged between Nancy and the Salpêtrière, Pierre Janet (1859-1947) was at work at Le Havre gathering clinical observations on which to base his dissertation. Born in Paris, Janet entered the École Normale Supérieure in 1879, placing second in the extremely competitive examinations of the agrégation. Shortly thereafter he took up a professorial position in philosophy at the Lyceum in Le Havre where he remained until the acceptance of his dissertation. Upon receipt of the degree, he moved to Paris to study medicine and pursue clinical research under Chariot at the Salpêtrière.

Janet's dissertation, L'automatisme psychologique brought together a wealth of related clinical information on a variety of abnormal mental states related to hysteria and psychosis. Dividing such states into total (involving the whole personality) and partial (part of the personality split from awareness and following its own psychological existence) automatisms, Janet employed automatic writing and hypnosis to identify the traumatic origins and explore the nature of automatism. Syncope, catalepsy, and artificial somnambulism with post-hypnotic amnesia and memory for prior hypnotic states were analysed as total automatisms. Multiple personalities, which Janet called ‘successive existence,’ partial catalepsy, absent-mindedness, phenomena of automatic writing, post-hypnotic suggestion, the use of the divining rod, mediumistic trance, obsessions, fixed ideas, and the experience of possession were treated as partial automatisms.

What is most important, Janet brought these phenomena together within an analytic framework that emphasized the ideomotor relationship between consciousness and action, employed a dynamic metaphor of psychic force and weakness, and stressed the concept of ‘field of consciousness’ and its narrowing because of depletion of psychic force? Within this framework, Janet analysed the peculiar fixation of the patient on the therapist in rapport about the distortion of the patient's perception, and related hysterical symptomatology to the autonomous power of ‘idées fixes’ split from the conscious personality and submerged in the subconscious. Although careful to avoid direct discussion of the therapeutic implications of his work draws from a substantiating medical dissertation, Janet laid the foundations for his own and Freud's later therapeutic approaches through his demonstration of the origins of splitting in psychic traumas in the patient's history.

Indeed, it was but a short leap from the work of Chariot, Bernheim, and Janet to that of Josef Breuer (1842-1925) and Sigmund Freud (1856-1939). In 1893, Breuer and Freud published a short preliminary communication, ‘Ueber den psychischen Mechanismus hysterische Phänomene’ in the Neurologische Centralblatt. The origin of the Breuer and Freud paper lay in Breuer's work with the famous patient Anna O.

Although actual details of the case of Anna O. as described by Bremer, who undoubtedly took pains to disguise his patient, and many years later by Jones (1953/1957) are at considerable variances with one another and probably with the facts of the case, it is known that the alleviation of Anna O's symptoms occurred only as the patient, under hypnosis, provided Bremer in reverse chronological order with an account of the exact circumstances under which each symptom appeared. Only when she had traced the final symptom back to the traumatic circumstances of its occurrence was she cured. Anna O's cure by this ‘cathartic’ method, which involved bringing the trauma to consciousness and allowing it to discharge through effect, words, and guided associations, has often been seen, and was thought by Freud, to be the starting point for psychoanalysis.

In the seminal work of Janet and in the critical transitional paper of Bremer and Freud, we see the culmination of developments that had begun with Puységur's elaboration of the doctrines of Mesmer. In a little more than a hundred years, a huge corpus of evidence and relational neurological functions and psychological theories that are dynamically irrevokable, least of mention, there is to believe that the related mental states, or their events -mesmeric trance states, rapport, the therapist's will to cure, the concentration of attention, mental suggestion, psychic trauma, the dissociation of consciousness, and catharsis -could affect radical alterations in the state of the body. No psychologist writing in the 1890s could afford to ignore this rich material and its implications for conceptualization of the nature of the mind/body relationship. William James, as we will see, was no exception. According to the received view (Boring, 1950), scientific psychology began in Germany as a physiological psychology born of a marriage between the philosophy of mind, on the one hand, and the experimental phenomenology that arose within sensory physiology on the other. Philosophical psychology, concerned with the epistemological problem of the nature of knowing mind in relationship to the world as known, contributed fundamental questions and explanatory constructs; sensory physiology and to a certain extent physics contributed experimental methods and a growing body of phenomenological facts.

In one version of this story that can be traced back at least to Ribot (1879), the epistemology of the 17th and 18th centuries culminated in the work of Kant, who denied the possibility that psychology could become an empirical science on two grounds. First, since psychological processes vary in only one dimension, time, they could not be described mathematically. Second, since psychological processes are internal and subjective, Kant also asserted that they could not be laid open to measurement. Herbart, so the tale goes, answered the first of Kant's objections by conceiving of mental entities as varying both in time and in intensity and showing that the change in intensity over time could be mathematically represented. Fechner then answered the second objection by developing psychophysical procedures that allowed the strength of a sensation to be scaled. Wundt combined these notions, joined them to the methods of sensory physiology and experimental phenomenology and, in 1879, created the Leipzig laboratory.

While there is undoubted truth in the received history, like all rationalizing reconstructions, it tends greatly to oversimplify what is an exceptionally complex story. Within the past 20 years, as primary resource materials have become more widely available and as larger numbers of historians have entered the arena, the received view has been amended often. Within the context of this exhibit catalogue, it will not, of course, be possible to address this complexity. The reader who is interested, however, is referred to the Journal of the History of the Behavioural Sciences and to Bringmann and Tweney (1980), Danziger (1990), Rieber (1980), and Woodward and Ash (1982) among others.

Because so many psychologists are at least broadly familiar with the lines of Boring's story of the rise of experimental psychology, because the story has been so frequently retold in the many other textbook histories, and because it is a much more complex tale that it at first appears, this section and the two to follow will sketch only the barest outlines of the intellectual developments that led from Locke to Kant, from Bell to Müller, and from Fechner to Wundt. Psychologists who have not read Boring are strongly encouraged to do so. Despite its limitations, it is still the point of origin from which much of contemporary scholarship proceeds. Perhaps even more important, it is the history of psychology that has become part and parcel of American psychology's view of itself.

Immanuel Kant (1724-1804) was born, lived, and died at Königsberg, in East Prussia. It is said that in the entire course of his life, he never travelled more than forty miles from the place of his birth. The suggestion from Ribot that 18th century philosophy culminated in the work of Kant was probably not an unreasonable one; although it might be an even fairer appraisal of Kant's influence to say that 19th and 20th century philosophy followed Kant much as the earlier philosophy had followed Descartes. Kant's indirect influence on scientific psychology was therefore enormous. His direct contributions, although admittedly more circumscribed, were also very important

One such contribution, as we have already noted, was Kant's defining the prerequisites that would need to be met for psychology to become an empirical science. Another consisted of a bonafide psychological treatise, Anthropologie in pragmatischer Hinsicht, published in 1798. Long ignored, probably in part because of its pronounced sympathy for as soon as to be a discredited physiognomy, the Anthropologie is, nonetheless, a fascinating little book. Here Kant analyses the nature of the cognitive powers, feelings of pleasure and displeasure, affects, passions, and character in a denial of the possibility of an empirical science of conscious process. The Anthropologie went through two editions during Kant's lifetime and several later printings and helped to define the context within which not only Herbart and Fechner but phenomenologically oriented physiologists such as Purkyne, Weber, and Müller worked to establish the science of conscious phenomena that Kant was unable to envision.

Boring (1950) has pointed out that between the years remembered through about the 1800s and well through to bout 1850, when several discoveries in physiology helped lay the foundation for the eventual rise of experimental psychology. The events’ particularity of interest are: (a) the first elaboration of a distinction between sensory and motor nerves; (b) the emergence of a sensory phenomenology of vision and of touch; and © the articulation of the doctrine of specific nerve energies, including the related view that the nervous system mediates between the mind and the world. While these discoveries were being made, two major developments in philosophical psychology were also occurring: the elaboration of secondary laws of association and the first attempt at a quantitative description of the parameters affecting the movement of ideas above and below a threshold.

Johannes Müller (1801-1858) was born in Coblenz and educated at the University of Bonn. He received his medical degree in 1822 and, after a year in Berlin, was habilitated as privatdozent at Bonn, where he rose eventually to the professoriate. In 1833, he left Bonn to assume the prestigious Chair of Anatomy and Physiology at the University of Berlin. His most important contributions to the history of experimental psychology were the personal influence that he exerted upon younger colleagues and students, including Hermann von Helmholtz, Ernst Brücke, Carl Ludwig, and Emil DuBois-Reymond, and the systematic form he gave to the doctrine of the specific energies of nerves in the Handbuch der Physiologie des Menschen für Vorlesungen, published between 1834 and 1840.

Although Müller had enunciated the doctrine of specific nerve energies as early as 1826, his presentation in the Handbuch was more extensive and systematic. Fundamentally, the doctrine involved two cardinal principles. The first of these principles was that the mind is directly aware not of objects in the physical world but of states of the nervous system. The nervous system, in other words, serves as an intermediary between the world and the mind and thus imposes its own nature on mental processes. The second was that the qualities of the sensory nerves of which the mind receives knowledge in sensation are specific to the various senses, the nerve of vision being normally as insensible to sound as the nerve of an audition is to light.

As Boring (1950) pointed out, there was nothing in this view that was completely original with Müller. Not only was much of the doctrine contained in the work of Charles Bell, the first of Müller's two most fundamental principles was implicit in Locke's idea of ‘secondary qualities’ and the second incorporated an idea concerning the senses that had long been generally accepted. What was important in Müller was his systematization of these principles in a handbook of physiology that served a generation of students as the standard reference on the subject and the legitimacy he lent the overall doctrine through the weight of his personal prestige.

After Müller, the two problems of mind and body, the relationship of mind to brain and nervous system and the relationship of mind to a world were inextricably linked. Although Müller did not himself explore the implications of his doctrine for the possibility that the ultimate correlates of sensory qualities might lie in specialized centres of the cerebral cortex or develop some sensory psychophysics, his principle of specificity lay the groundwork for the eventual localization of cortical function and his view of the epistemological function of the nervous system helped define the context within which techniques for the quantitative measurement of the mind/world relationship emerged in Fechner's psychophysics.

It is in the work of Gustav Theodor Fechner (1801-1887) that we find the formal beginning of experimental psychology. Before Fechner, as Boring (1950) tells us, there was only psychological physiology and philosophical psychology. It was Fechner ‘who performed with scientific rigour those first experiments which laid the foundations for the new psychology and still lie at the basis of its methodology’

On the 24th of March 1879, however, Wundt submitted a petition to the Royal Saxon Ministry of Education in which he formally requested a regular financial allocation for the establishment and support of a collection of psychophysical apparatus. Although his request was denied, Wundt seems as early as the Winter of 1879/1880 to have nonetheless allowed two students, G. Stanley Hall and Max Friedrich, ‘to occupy themselves with research investigations.’ This research took place in a small classroom in the Konvict Building that had earlier been assigned to Wundt for use as a storage area. Humble though it may have been, this small space constituted the first laboratory in the world devoted to original psychological research.

Experimental psychology, born with Fechner, nurtured by Helmholtz and Donders, was to be raised by Wundt. Over the years until his retirement in 1917, Wundt served as the de facto parent of the ‘new’ psychology. Students from all over the world, especially from the United States, journeyed to Leipzig to learn experimental technique and to return to their home institutions imbued with the spirit of scientific psychology.

To occupy oneself with history is not a matter of simple curiosity. It would be so if history were a simple science of the past. But: (1) History is not a simple science. (2). One does not make one’s home the singularity that can only to grasp into its self that one can be the accompaniment within the past, inasmuch as it no longer exists. History is not a simple science, but rather there exists a historical reality. Historicity, in fact, is a dimension of the real being we call 'man'.

And this historicity does not arise exclusively or primarily because of the fact that the past advances toward a present, and pushes it on toward the future. This later is a positive interpretation of history that is completely inadequate. It presupposes, in fact, that the present is just something that passes, and that the passing means what once was no longer is. The truth on the contrary is that an existing reality, and hence one that is present, man, finds himself constituted partially through a possession of himself in such a form that when he turns in upon himself, he discovers himself being what he is because he had a past and is being formed for a future. The ‘present’ is that marvellous unity of these three moments whose successive unfolding constitutes the historical trajectory, the point at which man, a temporal being, paradoxically becomes the tangent to eternity. Since Boethius, in fact, the classical definition of eternity has involved not just ‘an inter-mirabilis vita,’ as a never-ending life, but ‘tota simul et perfecta possessio.’ Furthermore, the reality of man present is constituted among other things by that concrete point of tangency whose geometric locus is termed the situation. Upon entering into ourselves, we discover that we are in a situation that pertains to us constitutively, and in which our individual destiny is inscribed, a destiny elected by us sometimes, imposed on us others. And while the situation does not ineluctably predetermine either the content of our life or that of its problems, it clearly circumscribes the general nature of those problems, and above all limits the possibilities for their solution. Hence, history as a science is much more a science of the present than a science of the past. In respect to philosophy, this is even truer than it could be for any other intellectual occupation, because the character of philosophical knowledge makes of it something constitutively problematic. Zetoumene episteme, the sought after science, Aristotle usually termed it. Therefore it is pot at all strange that to profane eyes, the problem has an atmosphere of discord.

In history we encounter three distinct conceptions of philosophy, emerging ultimately from three dimensions of man: (1) Philosophy as a knowledge about things (2) Philosophy as a direction for the world and for life. (3) Philosophy as a way of life and therefore as something that happens.

In reality, these three conceptions of philosophy, corresponding to three different conceptions of the intellect, lead to three completely different forms of intellectuality. The world has continued to nourish itself on them, simultaneously and successively, at times even in the person of one thinker. The three converge in a special way in our situation, and again keenly and urgently pose the problem of philosophy (and of intellect itself). These three dimensions of the intellect have reached us, perhaps somewhat dislocated, through the channels of history. The intellect has itself begun to pay for its own deformation. In trying to reform itself, it seems readily sure, in that the future new forms of intellectuality. All of the earlier ones, they will be defective, or rather limited. However that does not disqualify them, because man is always what he is, but thanks are by his restrictive nature, as too, are the limitations, for which permit of him of choice, for which he can be. And if, by his perceptivity that their own limitations are the intellectuals of that lived of that time, perhaps, a returning source from which they can depart, just as we see ourselves referred to identify the place of which we depart. And this is history: a situation that implies another previous one, as something real making possible our own situation. Thus, to occupy oneself with history is not a simple matter of curiosity; it is the very movement to which the intellect sees itself subjected when it embarks on the enormous task of setting itself in motion starting from its ultimate source. Therefore the history of philosophy is not extrinsic to philosophy itself, as the history of mechanics could be to mechanics. Philosophy is not its history, but the history of philosophy is philosophy, because the turning in of the intellect upon itself, in the concrete and radical situation in which it finds itself placed, is the origin take-off point for philosophy. The problem of philosophy is nothing but the problem of the intellect. With this affirmation, which ultimately goes back to old Parmenides, philosophy began to exist on the earth. And Plato used to tell us, moreover, that philosophy is a silent dialogue of the soul with itself concerning all things in being.

Still, the practising scientist will only with difficulty succeed in freeing himself from the notion that philosophy becomes lost in an abyss of discord, if not throughout its domain, at least insofar as it involves knowledge about things.

It is undeniable that throughout its history, philosophy has understood its own definition as a knowledge about things in quite diverse ways. But the first responsibility of the philosopher must be that of guarding himself against two antagonistic tendencies that spontaneously arise in a beginning spirit: That of losing oneself in skepticism and that of deciding to fit tightly polemically, as having a difference of opinion across one system instead of another, even if it is that we are as oriented differently of our position in life, only that if we could be formulated. We will renounce these attitudes. And if we now review the rich collection of definitions, we cannot fail to be overwhelmed by the impression that a very serious matter is at the heart of this diversity. If the conceptions of philosophy as a theoretical form of knowledge are truly so diverse, it is clear that this diversity means that not only the content of its solutions, but the very idea of philosophy continues to be problematic. The diversity of definitions manifest the problem of philosophy itself as a true form of knowledge about things. But to think that the existence of such a problem could disqualify philosophy as its theoretical knowledge is to condemn the paradigms by which of science has given by oneself the perpetual persistence, which, perhaps, leaves its shoes outside its vestibule. The problems of philosophy are not, at bottom, other than the problem of philosophy.

But perhaps the question will resurface with new urgency when we try to pin down the nature of this theoretical knowledge. Nor is the problem even new. For quite some time, several centuries in fact, this question has been formulated another way: Does philosophy have scientific character? However, this manner of presenting the problem is not quite the same. According to it, ‘knowledge about things’ acquires its complete and exemplary expression in what is termed ‘a scientific form of knowledge.’ And this supposition has been decisive while philosophy the modernity of times due, stood very still.

In diverse ways, in fact, it has been repeatedly observed that philosophy is quite far from being a science, that in most of its hypotheses it does not go beyond an attempt to be scientific. And this may lead either to skepticism about philosophy, or to maximum optimism about it, as occurred in Hegel when in the opening pages of the Phenomenology of the Spirit he roundly affirms that he proposes to ‘help to bring philosophy nearer to the form of science, . . . show that the time process does raise philosophy to the level of scientific system . . .’ And he also affirms that it is necessary for philosophy to abandon, its character of love and of wisdom to be converted into some activated wisdom. (For Hegel, ‘science’ does not mean science in the usual sense.)

With a different objective, but with less energy, Kant begins the preface to the second edition of the Critique of Pure Reason by saying:

Whether the treatment of knowledge lies within the province of reasons served or does not follow the secure path of a science, is easily to be determined from the outcome. For if after elaborate preparations, frequently renewed, it is brought to a stop immediately it nears its goal; if often it is compelled to retrace its steps and strike into some new line of approach; or again, if the various participants are unable to agree in any common plan of procedure, then we may rest assured that it is very far from entering upon the secure path of a science, and is indeed a mere random groping.

And in contrast to what occurs in logic, mathematics, physics, etc., with respect to metaphysics we see that . . . though it is older than all other sciences, and would survive even if all the rest were swallowed up in the abyss of an all-destroying barbarism, it has not yet had the good fortune to enter upon the secure path of a science.

A quarter of a century ago Husserl published a vibrant study in the periodical Logos, entitled ‘Philosophy as a Strict and Rigorous Science.’ In it, after having shown that it would be nonsense, for example, to discuss a problem of physics or mathematics so the participants injected into the discussion their own points of view, their opinions, preferences, or Weltanschauung, Husserl boldly proposes the necessity of making philosophy likewise into a science of apodeitic and absolute evidence. But in him last analysis, he merely refers to the work of Descartes. Descartes, very cautiously but at bottom saying the same thing, begins his Principles of Philosophy as follows: As we were at once children, and as we formed various judgements regarding the objects presented to us, when yet we had not the entire use of our reason, numerous prejudices stand in the way of our arriving at the knowledge of truth. Of these it seems impossible for us to rid ourselves, unless we undertake, once in our lifetime, to doubt of all these things in which we may discover even the smallest suspicion of uncertainty.

From this exposition of the question we may draw several important conclusions: 1. Descartes, Kant, and Husserl compare philosophy to the other sciences from the point of view of the type of knowledge that they yield: Does philosophy or does it not possess a type of apodeitic evidence comparable to that of mathematics or theoretical physics? 2. This comparison later reverts to the method that leads to such evidence: Does philosophy or does it not possess a method that leads securely, through internal necessity and not merely by chance, to types of evidence analogous to those obtain by the other sciences? 3. Finally it leads to a criterion: insofar as philosophy does not possess this type of knowledge and this secure method of the other sciences, its defect in that regard becomes an objection to its scientific character.

Now, faced with this statement of the question we must energetically affirm: 1. That the difference that Husserl, Kant and Descartes point out between science and philosophy, though very important, is not in the end sufficiently radical. 2. That the difference between science and philosophy is not an objection to the character of philosophy as a strict form of knowledge about things.

And this is so because, in the last analysis, their objection to philosophy derives from a certain conception of science that, without prior discussion, is assumed applicable to all strict and rigorous knowledge

The radical difference separating philosophy and the sciences does not arise from the scientific or philosophical state of knowledge. It seems, listening to Kant, that the only thing that matters is that, relative to its object, philosophy (in contrast to science) has not yet managed to give us a single reliable step leading to that state of knowledge. And we affirm that said difference is not sufficiently radical, because frankly it presupposes that the object of philosophy is there, in the world, and that all we need do is find the secure road leading to it.

The situation would be much more serious if what were problematic turned out to be the object of philosophy: Does the object of philosophy exist? This question is what radically separates philosophy from the other sciences. Whereas these latter starts from the possession of their object, and then simply study it, philosophy must begin by actively justifying the existence of its object, the possession of which is in fact the end, not the presupposition of its study. And philosophy can only be an on-going concern by constantly recovering the existence of its object. When Aristotle termed it Zetoumene episteme, he understood that what men sought was not only the method, but the very object of philosophy as well.

What does it mean to say that the existence of the object of philosophy is problematic?

If this meant simply that we were ignorant of what that object is, the problem, though serious, would ultimately be quite simple. It would be a question of saying either that humanity has not yet discovered that object, or that it is so complicated that its apprehension is still obscure. To be sure, the former is what happened for many centuries with each science and therefore their respective object: were not simultaneously discovered during history? ; some sciences were born later than others. On the other hand, if it were true that the object of philosophy were excessively complicated, the question would be that of trying to show it only to those minds who had acquired sufficient maturity. This would be analogous to the difficulty encountered by someone who tried to explain the object of differential geometry to a student of mathematics in elementary school. In either of these cases, owing to historical vicissitudes or didactic difficulties, we would be dealing with a deictic problem, with an individual or collective effort to point out (deixis) what that object is which goes about here lost among the other objects of the world.

Everything leads us to suspect that this is not so.

The problematicism surrounding the object of philosophy stems not only from a de facto failure to come upon it, but moreover from the nature of that object, which, in contrast to all others, is constitutively latent. Here we understand by ‘object’ the real or ideal thing with which science or any other human activity deals. Here, it is clear that: (1). This latent object is in no way comparable to any other object. Therefore, in as much as we what wish of saying, the object of philosophy, may, perhaps, find as a propounding asset, that we will move as if on the axial plane of thought, afar and above, that once removed we begin to participate of the other sciences. If each science deals with an object, either real, fictitious, or ideal, the object of philosophy is neither real, fictitious, nor ideal; it is something else, so much so, that it is not a thing at all. (2) We thus understand that this peculiar object cannot be found separated from any other object, be it real, fictitious, or ideal. Nonetheless, may it be, that it is included in all of them, without being identified with any particular one. This is what we mean when we affirm that it is constitutively latent, latent beneath every object. Since man finds himself constitutively directed toward real, fictitious, or ideal objects, with which he must create his life and elaborate his sciences, it follows that this constitutively latent object is because of its own nature essentially fleeting. 3. What this object flees from is none other than the simple glance of the mind. In contrast, then, to what Descartes maintained, the object of philosophy can never be formally discovered through a simplex mentis inspectio. Rather, after the objects beneath which it lies have been understood, a new mental act reworking the previous ones is necessary to position the object in a new dimension to make this other new dimension not transparent, but visible. The act by which the object of philosophy is made patent is not an apprehension, nor an intuition, but a reflection, a reflection that does not, as such, discover a new object among the others, but a new dimension of each object, whatever it may be. It is not an act that enriches our understanding of what things are. One must not anticipate that philosophy will tell us, for example, anything about physical forces, organisms, or triangles that is inaccessible to mathematics, physics, or biology. It enriches us simply by carrying us to another type of consideration.

To avoid misunderstandings, we should observe that the word 'reflection' is employed here in its most ingenuous and common meaning: an act or series of acts that, in one form or another return to an object of a previous act through this latter act. 'Reflection' here does not mean simply an act of meditation, nor an act of introspection, as when one speaks of reflective consciousness, as opposed to direct consciousness. The reflection here described consists of a series of acts through which the entire world of our life is placed in a new perspective, including the objects therein and all the scientific knowledge we may have acquired about them.

Secondly, note that though reflection and what it discovers to us cannot be reduced to a natural attitude and what it discovers to us. This does not mean that in one fashion or another, in one degree or another, reflection is not just as primitive and inborn as any natural attitude.

It follows then that the radical difference between science and philosophy does not fall upon philosophy as an objection. It does not mean that philosophy is not a rigorous form of knowledge, but only that it is a different type of knowledge. Whereas science is a knowledge that studies an object that is there, philosophy, since it deals with an object that because of its own nature hides, which is evanescent, will accordingly be knowledge that must pursue its object and detain it before a human gaze, which must conquer it. Philosophy is nothing but the active constitution of its own object; it is the actual carrying out of this act of reflection. Hegel's fatal error was just the opposite of Kant's. Whereas Kant, in short, divorced philosophy from any object of its own, thus making it refer to our mode of knowing. Hegel reifies about the object of philosophy, speaking as if only all of which is to every other object, there emerges of some dialectical awareness for which each one is sustained dialectically.

For the present it is unnecessary to further clarify the nature of the object of philosophy or its formal method. Here the only thing I wish to emphasize is that irrationalism not withstanding, the object of philosophy is strictly an object of knowledge, but this object is radically different from the rest. Whereas any science or any human activity considers things that are and such as they are (hos estin), philosophy considers them inasmuch as they are (hei estin, Metaphysics 1064). In other words, the object of philosophy is transcendental, and as such accessible only to a reflection. The ‘scandal of science’ not only isn't an objection to philosophy that must be resolved, but a positive dimension that it is necessary to conserve. Therefore Hegel said that philosophy was the world in reverse. The explanation of this scandal is the problem, content, and destiny of philosophy. Hence (although not quite what Kant said) ‘one does not learn philosophy, one learns to philosophize.’ And it is absolute certain that one only learns philosophy by starting to philosophize.

Every science, whether history or physics or theology (and likewise every natural attitude of life) refers too more than or less determinate of objects, with which man has already come into contact. The scientist may, then, direct himself to it, and set himself one or more problems about it the attempted solutions of which constitute the reality of science. If the presumed science does not yet enjoy a clear conception of what it pursues, then it is not yet a science. Any wavering on this point is an unequivocal sign of imperfection. That does not mean the science is immutable, but what changes in it is the concrete content of the solutions given to the one or more problems it has set out to solve. The problem itself, may be that of an unaltered remission that goes beyond the remains as such. The physical view of the universe has profoundly changed from Galileo to Einstein and quantum mechanics, however, in all these changes that have occurred within the scope of a general endeavour known and defined all along, viz., measurement of the universe. Sometimes perhaps the very formulation of the problem may change. But this occurs extremely rarely and across long spans of time. When it does happen it is owing to a new formulation of the problem that is as clear and determinate as the previous one, so that one may ask, indeed, whether ultimately the science has not ceased to be what it used to be, and become something else, a different science. Thus, in the Middle Ages physics studied the principles of the physical theories that were achievable. After Galileo it was measurement of the material universe. In both cases’ physics was a science when it had begun to tell itself what it sought to do.

Very different is the course of philosophy. In fact, philosophy begins by not knowing whether it has a proper object; at least, it does not start formally from the possession of an object. Philosophy presents itself, above all, as an effort, as a ‘pretension.’ And this, not because of any simple ignorance de facto or a simple lack of knowledge, but because of the constitutively latent nature of that object. Hence it follows that the strict separation between a problem that clearly differentiates in advance of its later solution, which is basic to all science and to all natural attitudes of life, loses its primary meaning about philosophy. Hence philosophy must be, first, a perennial revindication of its object (let us call it that), an energetic illumination of it and a constant and constitutive ‘making room.’ From Parmenides' entity (on), Plato's Ideas, and Aristotle's analogical being as such, up to Kant's transcendental conditions of experience and the absolute of Fichte, Schelling, and Hegel, passing through all the theological strata of medieval thought and the first centuries of the modern era, philosophy has been primarily a justification of or demonstrative effort for the existence (‘sit venia verbo’) of its object. Whereas science deals with an object that it already clearly possesses, philosophy is the effort directed toward a progressive intellectual constitution of its own object, the violence of yanking it from its constitutive latency and clearly revealing it. Nonetheless, philosophy might exist for the revindicating of itself, and in one of its formal dimensions consists in ‘opening paths.’ Consequently, philosophy cannot have what is the greater ascendancy than fixed by the intellectual narrowness which de facto oppresses the philosopher.

In virtue of this, it is only clear to the philosopher after he finds himself philosophizing what a mighty labour he carried out to reach the point where he could begin to philosophize. And this is true whether one deals with obtaining rigorous evidence or rising to transcendental intuitions. In this labour of opening a path one sketches and outlines the figure of the problem. It is possible for the philosopher to have begun with a certain subjective intellectual purpose. But this does not mean that such a beginning is formally the origin of his philosophy. And if we agree that the nature of the problem is the origin of principles, we must say that, in philosophy, the origin is the end, moreover in its first original and radical ‘step’ all of philosophy is already there. Throughout this process philosophy properly speaking does not evolve, is not enriched with new characteristics; rather, the characteristics become more explicit, they continually appear as aspects of a self-constitution. Whereas an immature science is imperfect, philosophy is the very process of its own maturity. The rest is dead academic and scholarly philosophy. Hence, in contrast to what happens in science, philosophy must mature in each philosopher. And therefore that which properly constitutes its history is the history of the idea of philosophy. Hence the original relationship existing between philosophy and its history must be clarified.

It may occasionally happen that the philosopher begins with an already existing concept of philosophy. But, what meaning or function does such a concept have within philosophy? It is, obviously, a concept that he, the philosopher has created and therefore is his possession or property. But, once things are underway, because philosophy consists of the ‘opening a path,’ it follows that therein the idea of philosophy is constituted. The definition of physics is not the work of physical science, whereas the work of philosophy is the conquest of its idea of itself. On this point, that initial movement has no bearing whatsoever; philosophy has achieved its own consistency, and with it an adequate concept, the concept which philosophy has created for itself. Nor is it any longer the philosopher who bears the concept of philosophy, as happened at the beginning; rather, philosophy and its concept are what bear the philosopher. In that apprehension or conception that the concept is, it is no longer the mind that apprehends or conceives philosophy, but philosophy is that what apprehends and conceives in the mind. The concept is not the property of the philosopher, but rather the philosopher is the property of the concept, because these latter springs from what philosophy is in it. Philosophy is not the work of the philosopher; the philosopher is the work of philosophy.

From where, before and only before a mature philosophy do we see that it is not only possible but necessary to ask how far and in what way does that philosophy answer its own concept. A typical case, to speak only of recent history, is shown to us by German Idealism, from Kant to Hegel. It makes perfect sense to scrutinize this entire current of transcendental idealism, and determine with each philosopher an original philosophy, absolutely compatible with the common root of all of their thought, and even with Kant's singular merit of being the first to discover the root and bear the first fruits.

Rene Descartes was a famous French mathematician, scientist and philosopher. He was arguably the first major philosopher in the modern era to try to defeat skepticism. His views about knowledge and certainty, and his views about the relationship between mind and body have been very influential over the last three centuries.

One source of this interest in method was ancient mathematics. The thirteen books of Euclid's Elements were some models of knowledge and deductive method. But how had all this been achieved? Archimedes had made many remarkable discoveries. How had he come to make these discoveries? The method in which the results were presented (sometimes called the method of synthesis) was clearly not the method by which these results were discovered. So, the search was on for the method used by the ancient mathematicians to make their discoveries (the method of analysis). Descartes is clearly convinced that the discovery of the proper method is the key to scientific advance. For more extended purposes and detailed discussion of these methods.

In November 1628 Descartes was in Paris, where he made himself famous in a confrontation with Chandoux. Chandoux claimed that science could only be based on probabilities. This view reflected the dominance in French intellectual circles of Renaissance skepticism. This skptical view was rooted in the religious crisis in Europe resulting from the Protestant Reformation and had been deepened by the publication of the works of Sextus Empiricus and reflections on disagreements between classical authors. It was strengthened again by considerations about the differences in culture between New World cultures and that of Europe, and by the debates over the new Copernican system. All of this had been eloquently formulated by Montaigne in his Apology for Raymond Sebond and developed by his followers. Descartes attacked this view, claiming only that certainty could serve as a basis for knowledge, and that he himself had a method for attaining such certainty. In the same year Descartes moved to Holland where he remained with only brief interruptions until 1649.

In Holland Descartes produced a scientific work called Le Monde or The World that he was about to publish in 1634. At the point, however, he learned that Galileo had been condemned by the Church for teaching Copernicanism. Descartes’s book was Copernican to the core, and he therefore had it suppressed. In 1638 Descartes published a book containing three essays on mathematical and scientific subjects and the Discourse on Method. These works were written in French (rather than Latin) and were aimed at the educated world rather than simply academics. In 1641 Descartes followed this with the Meditationes de Prima Philosophia (Meditations on First Philosophy). This short work is more metaphysical than scientific, and aims to establish the certain foundations for the sciences that Descartes had announced in his confrontation with Chandoux in 1628. (For a more detailed account of this work see Structure of the Meditations. The work was published with Objections and Replies from a six and then seven philosophers and theologians, including Thomas Hobbes, Pierre Gassendi and Antoine Arnauld.

After the Meditations, Descartes produced The Principles of Philosophy in 1644, the most comprehensive statement of his mature philosophy and of the Cartesian system in general. Part (1) explains Descartes metaphysical views. Part (2) gives a detailed exposition of the principles of Cartesian physics. Part (3) applies those principles of physics to explain the universe, and Part (4) deals with a variety of terrestrial phenomena. Two more parts were planned, to deal with plants and animals and man, but were not completed. In 1648 Descartes published ‘Notes against a Program’ -a response to a pamphlet published anonymously by Henricus Regius, Professor of Medecine at the University of Utrecht. Regius had been an early and enthusiastic supporter of Descartes. Yet, once Regius published his Foundations of Physics Descartes complained that Regius had shamelessly used unpublished papers of Descartes to which he had access and had distorted Descartes' ideas. The ‘Notes’ both illustrate the kind of academic controversy in which Descartes was involved during this decade, but also provides some insight into his views about mind and his doctrine of innate ideas.

Descartes last work Les Passions de l'áme was written because of the correspondence that Descartes carried on with Princess Elisabeth of Bohemia. The work was written in French, and published in Amsterdam and Paris in 1649. This work (like the Principles) is composed of many short articles. Princess Elisabeth had raised the question of how the soul could interact with the body in 1643. In response to Elisabeth's questions, Descartes wrote short works that developed into the ‘Passions of the Soul.’ The work is a combination of psychology, physiology and ethics, and contains Descartes' theory of two way causal interactions via the pineal gland.

Two months before the publication of the Passions Descartes set sail for Stockholm, Sweden, at the invitation of Queen Christina of Sweden. Descartes' death in Stockholm of pneumonia, has regularly been attributed to the rigours of the Swedish climate and the fact that Descartes (no early riser) was sometimes required to give the Queen lessons as early as five in the morning. However unpleasant these conditions may have been, it seems plain that Descartes acquired his fatal malady because of nursing his friend the French ambassador (who had pneumonia) back to health.

Most academics are familiar with a comforting fable, subject to minor variations, about René Descartes and modern philosophy. Around 1640, Descartes philosophically crystallized a key transformation latent in Renaissance views of humanity. He moved the foundation of knowledge from humans fully embedded within and suited to nature to inside each individual. Descartes made knowledge and truth rest upon the individual subject and that subject's knowledge of his or her own capacities. This move permitted profoundly new and unconditional skepticism, than undermining universal knowledge by positing a uniformity of human subjects, this move ultimately guaranteed intersubjective knowledge. Knowledge became subjective and objective. Not content merely to make man himself the ground of knowledge, Descartes went further to make the human mind alone the source for knowledge, knowledge that modelled after pure mathematics. The new Cartesian subject ignored the manifold contributions of the body, and Descartes assumed all real knowledge could come only from a reason common to all humans. The universality of the knowing things and processes of knowing and not-knowing, are we to make of this causal event the Cartesian subject as one that is transcendental. Above all, mathematics, with its proof techniques, and formal thought, modelled on mathematics, exemplified those things that can be intersubjectively known by individual but importantly similar subjects.

Versions of this fable appear in numerous analyses, some quite sophisticated and textually based, some crude and dismissive. These versions provide grounds for praising or dismissing Descartes and the philosophical modernity he wrought. Rather than surveying or evaluating these appraisals, here I want merely to clarify and anchor historically the subject Descartes hoped his philosophy would help produce. This essay examines one set of exercises Descartes highlighted as propaedeutics to a better life and better knowledge: Becoming famous, for which it might be that if it were as little known through his geometry. Critics and supporters have too often stressed Descartes's dependence on or reduction of knowledge to a mathematical model without inquiring into the rather odd mathematics he actually set forth as this model. His geometry, neither Euclidean nor algebraic, has its own standards, its own rigour, and its own limitations.3. These characteristics ought radically to modify our view of Descartes's envisioned subject. Although the technical details of his geometry might seem interesting and comprehensible only to historians of mathematics, the essential features grounding Descartes's program can be made readily comprehensible. Descartes did far more than theoretically (if implicitly) invoke the knowing subject in his Meditations. To pursue his philosophy was nothing less than to cultivate and order oneself. He offered his revolutionary but peculiar mathematics as a fundamental practice in this philosophy pursued as a way of life. Let us move, then, from abstraction about Descartes to the historical quest for this way of life One way in which modern philosophy, roughly that beginning with Descartes, is supposed to be different from what came before it, is its emphasis on the problems of acquiring knowledge. This emphasis on knowledge likely has its origins in a variety of circumstances.

One of these is the Reformation crisis concerning religious knowledge and related events. Luther questioned the Catholic criterion of religious knowledge -the Rule of Faith as it is called -and thereby started a new religion with its own criterion of religious knowledge. The Rule of Faith says that religiously knowledge is determined by what Church fathers, Church Councils and the Popes say about any particular claim. Thus Church Councils have endorsed the doctrine of the trinity so anyone who claims that this doctrine is false is a heretic. Luther replaced the Rule of Faith with the claim that all Christians have the power 'of discerning what is right or wrong in matters of faith.' Luther finally made it clear that his new view amounted to this: What conscience is compelled to believe on reading scripture is true. This radical move changed Luther from just another reformer to the founder of a new religious sect. For many people it raised an enormous problem about religious knowledge. Which of the two criteria was the correct one? It was difficult for people to determine the answer to this question. For various reasons, which we will consider, this sceptical crisis about religious knowledge developed into a full blooded sceptical crisis about knowledge in general. So how does one acquire genuine knowledge?

One way to think about the problem of acquiring knowledge about the era we are discussing is to regard reason, the senses and faith as competing ways of getting at the truth about reality. One might hold, with Plato for example, that the senses will not get one to the truth about reality; that only reason will lead us to knowledge of reality and how to lead the best life and attain genuine happiness. Or one might argue that the senses provide knowledge of the world that is more basic than anything that reason tells us. Or, one might hold that both reason and the senses are poor guides and that only faith will reveal the way things really are.

Skepticism is the doctrine that knowledge is not possible. One can be either a universal skeptic who holds that no knowledge whatever is possible (Could this be true?) or simply a skeptic about one faculty, like the senses, or some particular branch of knowledge, such as religious knowledge or mathematical knowledge. Skepticism is intertwined in the competition among the faculties because an advocate of reason, for example, is likely to be sceptical of the ability of the other faculties to reach the truth. The Cambridge Platonists, for example, regarded the doctrine that the senses are more important than reason as the philosophy of beasts. For men share sense knowledge with the beasts, while reason sets man apart from the beasts. An advocate of faith, on the other hand, will be sceptical of the ability of reason and the senses to provide genuine knowledge. The great French essayist Michel de Montaigne is an able and interesting advocate of this last view.

There are philosophers with discriminate views, who hold that there is a place and legitimate sphere for each faculty, and one must figure out what the limits are to each. Rene Descartes holds that reason is considerably more important than the senses in that reason provides more basic knowledge than the senses. It tells us about the essences of things, which the senses do not. Nonetheless, Descartes holds that the senses have a place in our scientific attempts to understand the world. Descartes also holds that various truths can only be determined by faith. John Locke also, seeks to determine the limits of human understanding, what we can know and why, what role the senses and reason play, and what can only be believed or taken as an article of faith. For Locke, the senses and reflection provide the materials on which reason works. Faith operates beyond reason. Another strand that caused the interest in knowledge was the extraordinary advances made during this period in mathematics and natural philosophy or science as we now call it. European mathematicians were finally able to surpass the results of the Greek mathematicians of antiquity such as Euclid and Archimedes. Similarly natural philosophers were coming to reject Aristotelian physics and Ptolemaic cosmology and geography. With the work of Copernicus, Brahe, Galileo and Kepler, placed astronomy and physics were new understructure. Surely, these extraordinary advances represented real knowledge. The struggle between sceptical arguments and scientific achievement, not to mention the claims of religion was a real one. One can see all, but these concern meeting in thinkers like Descartes and Pascal.

Philosophers during this era were obsessed with methods for discovering and presenting truths. A method, in this context, supposes some systematic procedure, which, if followed, guarantees that one will hit upon the truth and avoid error. One source of this interest in method is Greek mathematics. Euclid's Elements of Geometry and the works of other ancient mathematicians provided a model of knowledge and proof. How was this wealth of mathematical knowledge discovered? The demonstration of the theorems does not seem to provide much insight in answering this question. So, mathematicians and philosophers in the fifteenth and sixteenth centuries began reflecting on the method of discovery that they called the method of analysis. Essentially the view that began to develop was that one would take apart the thing which one wished to understand, until one reached the basic and essential parts composing it. One would then analyse how the parts relate to one another and put them back together. By taking them apart in this way and then putting them back together one emerged with a new understanding.

Galileo uses a method that he called the Resolution-Compositive method. The whole which one is studying got resolved into its parts and then put back together or composed again. This resolution into parts often involves simplifying and abstracting parts.

Thomas Hobbes adopted this Galilean method to the study of man. Making the distinction between the complicated world in which there are good and bad, legitimate and illegitimate governments, and the state of nature in which there is no government is an exercise in the resolution of a whole into its parts. Once we see the nature of man in such a state, Hobbes thinks it becomes abundantly clear what the legitimate function of government is, however. We emerge from the exercise seeing clearly how to judge of the goodness and legitimatised governments from bad and illegitimate one’s. Locke and Spinoza, who both read Hobbes, perform similar analyses on the state, though with differing results. In the eighteenth century some analyses of the origins of language employ a similar method.

Descartes was extraordinarily interested in method. He wrote works like The Discourse on Method and gives quite remarkable examples of discoveries in geometry and other subjects that he claims were made from the methods he describes. In John Cottingham's book The Rationalists you will find chapter two devoted to a discussion of these methods in the works of Descartes, Spinoza and Leibniz.

Besides the method of analysis, Descartes is famous for employing what has become called the method of doubt in the Meditations to try to defeat skepticism. The method works like this. Descartes' puts forth a sceptical hypothesis concerning a certain class of his beliefs. (He does not want to doubt each belief individually as this would be impractical.) The classes that he generates turn out to be related to particular faculties, the senses, imagination and reason. He then tries to determine what can and what cannot be doubted by his sceptical hypothesis. If there are things that cannot be doubted on a particular sceptical hypothesis, he tries to generate a stronger sceptical hypothesis that will bring into doubt those things that could not be doubted on the previous hypothesis. Eventually, the application of this method leads him to the conclusion that there are a variety of things that cannot be doubted on the strongest possible sceptical hypothesis

Descartes proposed a dualistic relation between the conscious, volitional soul, and the rest of the brain and body. The interface worked both ways, with (processed) sense information going into consciousness, and volition proceeding in reverse to operate the motor system. Descartes recognised that much of what we do could be explained by more direct links between sensory stimuli and the motor system, so the soul was not essential for all actions. One-way Cartesianism is the belief in a kind of Cartesian Dualism, but where the soul is purely passive, having knowledge of what passes in the brain, but no ability to initiate actions. It has the illusion of doing so, because from its privileged position it can see actions in preparation before they occur. The following passage from my Neurophysiology (3rd Edition, 1996; Arnolds, London) tries to explain the idea to a relatively general audience.

'Nothing puzzles me more than time and space. Yet nothing troubles me less, as I never think about them'

Charles Lamb's reaction is not very different from that of most neurophysiologists to problems of mind, brain, and consciousness. This is of course a field that has been thoroughly dug over since the days of Descartes and Hume and indeed long before: and philosophers have every right to question whether mere empirical physiologists can add much to such a hoary debate, in which the various arguments have been rehearsed so exhaustively. But recent developments both in neurophysiology and in computer science -for £20 I can purchase an electronic device hardly bigger than a packet of cigarettes, which is the intellectual superior of half the animal kingdom -have so enlarged our notions of what classes of operation a physical system may in principle be capable of, that a great deal of earlier thought on the subject is now merely irrelevant. In brief, 'brain versus mind' is no longer a matter for much argument. Functions such as speech and memory, which not so long ago were generally held to be inexplicable in physical terms, have now been irrefutably demonstrated as carried out by particular parts of the brain, and to a large extent imitable by suitably programmed computers. So far has brain encroached on mind that it is now simply superfluous to invoke anything other than neural circuits to explain every aspect of Man's overt behaviour. Descartes' dualism proposed some non-material entity -the 'ghost in the machine' -that was provided with sense data by the sensory nerves, analysed them within itself, and then responded with appropriate actions by acting on motor nerves (the mind thus having the same relation to the body as a driver to his car: But what about free will? The ghost in such a scheme would observe the body's actions being planned, and see the commands being sent off to the muscles before the actions themselves began, and so one can well imagine how it might develop the illusion that because it knew what was going to happen, that it was itself the cause. For X, the distinction between 'I lift my arms' and 'My arms go up', in which Wittgenstein epitomised the notion of voluntary action, would amount simply to the distinction between those actions that it observed being planned, and those -such as reflex withdrawal from a hot object -which it did not. There is no implied necessity here for us to be deterministic in our actions -to an outsider we may appear to have free will -since the physical processes linking S and R can be as random and essentially unpredictable as we please. Such a scheme seems more intellectually satisfying than (a) or (b) without conflicting with our own feelings about ourselves. Unlike ©, does not merely evade the issue. The most serious objection to it is perhaps that it is difficult to see what on earth X is for, since it can't actually do anything. Perhaps it does just occasionally intervene. But in any case, what is the audience at a concert for? Or the spectators at a football match? The idea that I am being carried round by my body as a kind of perpetual tourist, a spectator of the world's stage, is not -on reflection -so very unattractive. René Descartes, the celebrated mathematician and physicist, is also often considered a founder of modern philosophy, as he sought new ways to move beyond Medieval Aristoteleanism and justify the science of his day. In his Discourse on Method he expresses his disappointment with traditional philosophy and with the limitations of theologies, only logic, geometry and algebra hold his respect, because of the utter certainty that they can offer us. Unfortunately, because they depend on hypotheses, they cannot tell us what is real (i.e., what the world is really like). Therefore Descartes proposes a method of thought incorporating the rigour of mathematics but based on intuitive truths about what is real, basic knowledge that could not be wrong (like the axioms of geometry). He calls into question everything that he thinks he has learned through his senses but rests his whole system on the one truth that he cannot doubt, namely, the reality of his own mind and the radical difference between the mental and the physical aspects of the world.

Descartes (late in our excerpt) suggests that sense experience might be like dreaming, i.e., vivid but not matching the way things really are. But what does he realize must be the case even if his senses cannot be trusted?

Good sense is the most evenly distributed thing in the world, for all people suppose themselves so well provided with it that even those who are the most difficult to satisfy in every other respect never seem to desire more than they have. It is not likely that everyone is mistaken, this attitude divulged upon the ability to judge and distinguish the truth from it’s the insincerity of falsehood, which is properly what one call’s good sense or reason, is in fact naturally equally distributed among all people. Thus the diversity of our opinions does not result from some of us being more reasonable than others, but solely from the fact that we conduct our thoughts along different paths, and consider different things . . . As far as reason--or good sense -is concerned, since it is the only thing that makes us human and differentiates us from the animals, I should like to believe that it is entirely present in each of us. . . .

I was nourished by study from my earliest childhood. Since I was convinced that this was the means to acquire a clear and certain knowledge of all that is useful in life, I had an extreme desire to learn. But as soon as I had finished a course of studies that usually culminates in one being accepted as one of the learned, I changed my opinion completely; for ‘I’ found myself troubled by so many doubts and errors that the only profit I had gained in seeking to educate myself was to discover ever more clearly the extent of my ignorance. Nevertheless I had been at one of the most famous schools in Europe, where I thought there must be wise men if such existed anywhere on earth. There I had learned all that the others learned. Besides, not satisfied with the knowledge that we were taught, I had poured over all the unusual and strange books that I could lay my hands on. In addition, I knew how others evaluated me. I did not want to be considered inferior to my fellow-students, even though some among them were already destined to take the places of my teachers. Finally, our century seemed to me to abound in as many wise spirits as any preceding one, which led me to suppose that I could judge the experience of others by my own, and to think that there was no such knowledge in the world such as I had been led to hope for . . .

I was especially pleased with mathematics because of the certainty and clarity of its proofs; but I did not as yet realize its true usefulness; and, thinking that it was only useful in the mechanical arts, I was astonished that, since its foundations were so firm and solid, no one had built something higher upon it. To the contrary, I felt that the writings of who had discussed morality were likely superb, magnificent palaces that were built on mere sand and mud: they greatly praised the virtues and made them appear more exalted than anything else in the world; but they did they did not sufficiently teach how to know them. Often that which they called by the fine name of ‘virtue’ was nothing but apathy, or pride, or despair, or parricide.

I revered our theology, and hoped as much as anyone else to get to heaven, however, having learned, as if it were certain, that the road to heaven is as open to the most ignorant as to the most learned, and that the revealed truths that lead one there are beyond our comprehension, I did not dare to submit them to my feeble reasoning, and I thought that to undertake successfully to examine them one would need some extraordinary, heavenly aid and beyond human ability.

Of philosophy I will say nothing except that, seeing that it had been developed by the finest minds that had lived over many centuries and that nevertheless there was no point in it that was not still under dispute, and consequently doubtful, I lacked the presumption to hope that I would succeed any better than the others. When I considered how many different opinions there, had been about the same subject put forward by learned men, whereas only one of them could have been correct, I considered that anything that was only probable was as good as false . . .

It is true that while I considered only the customs of other ordinary men, I found nothing in them to reassure me, and I noticed as much diversity among them as I had earlier done among the opinions of philosophers. The greatest benefit I received from this study was that, having observed many things that, while they seemed quite extravagant and ridiculous, were nevertheless commonly accepted as true and approved by great peoples, I learned not to believe too firmly in anything of which I had been persuaded only by example and custom. Thus I freed myself little by little from many errors that can dim our natural light and even make us less able to listen to reason. But after I had spent several years thus studying the book of the world and trying to get some experience, I one day resolved to study my own self, and to use all the powers of my mind to choose the path I should follow, which was much more successful, it seems to me, than if I had never left my country or my books.

When I was younger, I had studied a little among other branches of philosophy, logic, and among types of mathematics, geometrical analysis and algebra: three arts or sciences that seemed as if they ought to contribute something to my goal. But when I examined them, I realized that as far as logic was concerned, its syllogisms and most of its other methods serve only to explain to someone else that which one already knows, or even, like Lully's art, to speak foolishly of things one does not know, rather than actually to learn anything. Even though logic contains, in fact, many very true and good precepts, they are nevertheless mingled with so many others that they become harmful or superfluous, that it is almost as hard to separate them out as to carve of Diana or a Minerva from as yet, the untouched block of marble. Besides, as far as the analysis of the ancients or modern algebra is concerned, and besides the fact that they can deal only with very abstract matters that seem utterly useless, the former is always so restricted to the study of geometrical figures that it cannot exercise the understanding without greatly tiring the imagination. The latter is so restricted to certain rules and figures that it has become a confused, obscure art that perplexes the mind instead of being a science that cultivates it. So I thought that I had to look for some other method that, having the advantages of these three, would be free of their defects. Just as a multitude of laws often creates excuses for vices, so that the best regulated state is that which, having very few laws, makes those few strictly observed, instead of the great number or precepts that make up logic, I thought that the four following precepts would suffice, provided that I could make a firm, steadfast resolution not to violate them even once.

The first was to never accept anything as true which I could not accept as obviously true; that is to say, carefully to avoid impulsiveness and prejudice, and to include nothing in my conclusions but whatever was so clearly presented to my mind that I could have no reason to doubt it.

The second was to divide each of the problems I was examining in as many parts as I could, as many as should be necessary to solve them. The third, to develop my thoughts in order, beginning with the simplest and easiest to understand matters, in order to reach by degrees, little by little, to the most complex knowledge, assuming an orderliness among them, which did not at all naturally seem to follow one from the other. And the last resolution was to make my number carry through and into my ex post facto, as can be felt of me that I could be secure that for which I had not to leave out anything.

These long chains of reasoning, so simple and easy, which geometers customarily used to make their most difficult demonstrations, caused me to imagine that everything which could be known by human beings could be deduced one from the other in the same way, and that, provided only that one refrained from accepting anything as true which was not, and always preserving the order by which one deduced one from another, there could not be any truth so abstruse that one could not finally attain it, nor so hidden that it could not be discovered. And I had little trouble finding which propositions I needed to begin with, for I already knew that they would be the simplest and the easiest to know. . . . I took the best features of geometrical analysis and of algebra, and corrected all the defects of one by the other.

I had noticed for a long time that it was necessary sometimes to agree with opinions about ethics that I knew to be quite uncertain, even though they were indubitable, as I said earlier, since I wanted to devote myself solely to the search for truth, I thought that I should act in the opposite manner, and reject as absolutely false anything about which I could imagine the slightest doubt, so that I could see if there would not remain after all that something in my belief that could be called absolutely certain. So, because our senses sometimes trick us, I tried to imagine that there was nothing that is the way that we imagine it. Since there are people who are mistaken about the simplest matters of geometry, making mistakes in logic, and supposing that I was as likely to make mistakes as anyone else, I rejected as false all the reasoning that I had considered as valid demonstrations. Finally, considering that all our thoughts that we have when we are awake can also come to us when we are sleeping without a single one of them being true, I resolved to pretend that everything I had ever thought was no more true that the illusions in my dreams. But I immediately realized that, though I wanted to think that everything was false, it was necessary that of ‘me’ as the representation of who was doing the thinking was something that gave its resemblance to ‘I.’ Noticing that this truth -I think, therefore I am was so certain and sure that all the wildest suppositions of skeptics could not shake it, I judged that I could unhesitatingly accept it as the first principle of the philosophy for which I was seeking.

Then, examining closely what I was, and seeing that I could imagine that I had no body and that there was no world or place where I was, I could not imagine that I did not exist at all. On the contrary, precisely because I doubted the existence of other things it followed obviously and certainly that I did exist. If, on the other hand, I had only ceased to think while everything else that I had imagined remained true, I would have had no reason to believe that I existed; therefore I realized that I was a substance whose essence, or nature, is nothing but thought, and which, in order to exist, needs no place to exist nor any other material thing. So this self, which is to say the soul, through which I am what I am, is entirely separate from the body, and is even more easily known than the latter, so that even if I did not have a body, my soul would continue to be all that it is.

Descartes' first published work consists of three appendixes as follows: (A) La Dioptrique: This is a work on optics and his contribution is his approach through experimentation. Although Descartes does not cite previous scientists for the ideas he puts forward, the book does not consist of all new concepts.

The chief focus of this book is given in the law of refraction. This appears to have been taken from Snell's work, though, unfortunately, it is put forward in a way, which might lead a reader to suppose that the law was a result of the researches of Descartes. Descartes would seem to have repeated Snell's experiments when in Paris in 1626 or 1627, and it is possible that he subsequently forgot how much he owed to the earlier investigations of Snell. A large part of the optics is devoted to determining the best shape for the lenses of a telescope, but the mechanical difficulties in grinding a surface of glass to a required form are so great as to render these investigations of little practical use. Descartes seems to have been doubtful weather to regard the rays of light as proceeding from the eye and so to speak touching the object, as the Greeks have had to be perceived, that through which have so done, that they have practised authoritatively or as proceeding from the object, and so affecting the eye, least of mentions, that he considered the velocity of light to be infinite, although he did not deem the point particularly important.

(B) Les Météores; This is a work on meteorology and its importance is it being the first work, which attempts to conduct the study of weather on a scientific basis. It contains an explanation of numerous atmospheric phenomena, including the rainbow. Descartes was unacquainted with the fact that the refractive index of a substance is different for lights of different colours. Consequently, the explanation of the latter is necessarily incomplete. However many of Descartes' claims are not only wrong but could have easily been seen to be wrong if he had done some easy experiments. For example Roger Bacon had demonstrated the error in the commonly held belief that water, which has been boiled, freezes more quickly. However Descartes claims, . . . and we see by experience that water that has been kept on a fire for some time freezes more quickly than otherwise, the reason being that those of its parts that can be most easily folded and bent are driven off during the heating, leaving only those that are rigid. Despite its many faults, the subject of meteorology was set on course after publication of Les Météores. La Géométrie; This is by far the most important part of this work. The book is further divided into three books: the first two of these treat of analytical geometry, and the third includes an analysis of the algebra then current.

The first book commences with an explanation of the principles of analytical geometry, and contains a discussion of a certain problem, which had been propounded by Pappus in the seventh book of his and of which some particular cases had been considered by Euclid and Apollonius. The general theorem had baffled previous geometricians, and it was in the attempt to solve it that Descartes was led to the invention of analytical geometry. The full enunciation of the problem is rather complicated, but the most important case is to find the locus of a point such that the product of the perpendiculars on m given straight lines will be in a constant ratio to the product of the perpendiculars on n other given straight lines. The ancient geometricians had solved this geometrically for the case m = 1, n = 1, and the case m = 1, n = 2. Pappus had further stated that, if m = n = 2, the locus is a conic, but he gave no proof; Descartes also failed to prove this by pure geometry, but he showed that the curve can be represented by an equation of the second degree, that is, a conic.

In the second book Descartes divides curves into two classes, namely, geometrical and mechanical curves. He defines geometrical curves as those that can be generated by the intersection of two lines each moving parallel to one co-ordinate axis with ‘commensurable’ velocities; by which terms he means that dy/dx is an algebraical function, as, for example, is the case in the ellipse and the cissoids. He calls a curve mechanical when the ratio of the velocities of these lines is ‘incommensurable’; by which term he means that dy/dx is a transcendental function, as, for example, is the case in the cycloid and the quadratrix. Descartes confined his discussion to geometrical curves. Descartes also paid particular attention to the theory of the tangents to curves -as perhaps might be inferred from his system of classification just alluded to. The then current definition of a tangent at a point was a straight line through the point such that between it and the curve no other straight line could be drawn, that is, the straight line of closest contact. Descartes proposed to substitute for this a statement equivalent to the assertion that the tangent is the limiting position of the secant; Fermat, and at a later date Maclaurin and Lagrange, adopted this definition. Barrow, followed by Newton and Leibnitz, considered a curve as the limit of an inscribed polygon when the sides become indefinitely small, and stated that the side of the polygon when produced became in the limit a tangent to the curve. Roberval, on the other hand, defined a tangent at a point as the direction of motion at that instant of a point that was describing the curve. The results are the same whichever definition is selected, but the controversy as to which definition was the correct one was none the less lively. In his letters’ Descartes illustrated his theory by giving the general rule for drawing tangents and normals to roulette.

The method used by Descartes to find the tangent or normal at any point of a given curve was substantially as follows. He determined the centre and radius of a circle, which should cut the curve in two consecutive points there. The tangent to the circle at that point will be the required tangent to the curve. In modern textbooks it is usual to express the condition that two of the points in which a straight line (such as y = mx + c) cuts the curve will coincide with the given point: this enables us to determine m and c, and thus the equation of the tangent there is determined. Descartes, however, did not venture to do this, but selecting a circle as the simplest curve and one to which he knew how to draw a tangent, he so fixed his circle as to make it touch the given curve at the point in question, and thus reduced the problem to drawing a tangent to a circle. However, he only applied this method to curves, which are symmetrical about an axis, and he took the centre of the circle on the axis.

The third book of the Géométrie contains an analysis of the algebra. The influence of the book is that it has affected the language of the subject by fixing the custom of employing the letters at the beginning of the alphabet to denote known quantities, and those at the end of the alphabet to denote unknown quantities. This was a further development toward the development of algebraic notations. In addition, Descartes also invented the system of indices (e.g., in x2, x3, x4 . . . ) to express the powers of numbers, which are now widely used. It is doubtful whether or not Descartes recognized that his letters might represent any quantities, positive or negative, and that it was sufficient to prove a proposition for one general case. He was the earliest writer to realize the advantage to be obtained by taking all the terms of an equation to one side of it. He realized the meaning of negative quantities and used them freely. In this book he made use of the rule, which is known as Descartes’ rule of signs, for finding the limit to the number of positive and of negative roots of an algebraical equation, and introduced the method of indeterminate coefficients for the solution of equations. He believed that he had given a method by which algebraical equations of any order could be solved, but in this he was mistaken.

In a book named The Scientific Work of René Descartes (1987), J.F. Scott summarizes the importance of this work in four points, (I) -He makes the first step toward a theory of invariants, which at later stages derelativises the system of reference and removes arbitrariness. (ii). Algebra makes it possible to recognise the typical problems in geometry and to bring together problems that in geometrical dress would not appear to be related at all.

(iii). Algebra imports into geometry the most natural principles of division and the most natural hierarchy of method.

(iv) Not only can questions of solvability and geometrical possibility be decided elegantly, quickly and fully from the parallel algebra, without it they cannot be decided at all.

René Descartes (1596-1650) is primarily associated with Philosophy his Discourse on Method and Meditations have even led him to be called the ‘Father of Modern Philosophy.’ In his most celebrated argument, Descartes attempted to prove his own existence via the now hackneyed argument, ‘I think therefore I am.’ However, it should not be forgotten that René Descartes applied his system to investigations in physics and mathematics, with real success, playing a crucial role in the development of a link between algebra and geometry -now known as analytic geometry, a subject defined by Webster's New World Dictionary as ‘the analysis of geometric structures and properties principally by algebraic operations on variables defined in terms of position coordinates.’ Simply put, analytic geometry translates problems of geometry into ones of algebra. Before the Cartesian plane and analytic geometry, most mathematicians considered (synthetic) geometry and (diophantine) algebra to be two different fields of study. To anyone that has taken a high school course in analytic geometry, that notion seems ridiculous, or even incomprehensible, but to mathematicians of 500 years ago or more, solving geometric problems using the methods of algebra probably seemed equally absurd.

In fact, as will be evident later in the paper, much of our tenth grade ‘vocabulary’ (using x2 to represent the equation of a parabola, using terms ‘a’, ‘b’, ‘c’, to be an indication of indeterminate parameters, etc. . . . ) can trace their roots directly back to the work o f René Descartes, building on the algebra of the late 16th century.

How did it happen that someone who had more interest in determining whether or not we live in a dream world than in, for example, determining the mean and extreme ratio mathematically, come fundamentally to change not only the way we do geometry, but also the way we think about geometry? To understand the answer, it will be useful to examine the life of René Descartes and the period in which he flourished.

Descartes' father was a lawyer and judge, and his parents belonged to the noblesse de robe, the social class of lawyers, between the bourgeoisie and the nobility. As such he received and excellent education, and had the financial resources to continue his studies at the Jesuit College of the town of La Flhche in Anjou. Men are a product of their times, and René Descartes was no exception. After hearing that Galileo Galilei, among others, both pronounced, and persuasively argued, that the sun did not revolve around the Earth, but rather vice versa, and that, in addition, the earth made a complete revolution daily, Descartes began to question whether any of the senses could be trusted as a source of information. After all, his sense of motion clearly demonstrated that the Earth is stationary, while it was ‘truly’ rotating and moving at a great speed through space. If his senses could be wrong in regard to something so basic, was not it possible to be equally mis taken in other fundamental areas as well? Nonetheless, according to Descartes ‘I concluded that I might take as a rule the principle that all things that we very clearly and obviously conceive are true: only observing, however, that there is some difficulty in rightly determining the objects that we distinctly conceive.’ Descartes held knowledge up to a very severe standard. According to Descartes, the four rules of logic were: (1) To accept as true only those conclusions that were clearly and distinctly known to be true.

(2) To divide difficulties under examination into as many parts as possible for their better solution. (3) To conduct thoughts in order, and to proceed in stages from the simplest and easiest to know, to more complex knowledge. (4) In every case to take a general view so as to be sure of having omitted nothing.

Because of his severe standard, Descartes' quest for underlying truths blossomed into a distinct penchant for mathematics, where proofs were just that -undeniable knowledge. Descartes' fourth standard conveys more than just a hint of the mathematician as well as the philosopher. Often in mathematics, solving a simple problem can be trivial. However, the formulation of a general rule to solve the problem can be infinitely more useful. Descartes seems to say in his fourth rule that the general case is the one of great importance, not the specific problem. Eventually Descartes published his ideas in a little book, or appendix, titled La Géomitrie, in 1637. Descartes major contribution in this book is considered to lie in the idea of a coordinate system, allowed problems that were considered to be strictly geometric to pass over into algebra. Although the association of algebra and geometry was proposed even by the Greeks, and taken up anew as a program by Vihte, no satisfying procedure had been found to merge the two disciplines into one ( until the development of the Cartesian plane. Thus, Descartes was not the first to attempt to develop a coordinate plane, but his method has been the one that achieved the desired goal. Both the Greeks and Egyptians had developed a numerical coordinate system (driven by its relevance to astronomy and cartography), but with little mathematical development. ‘Hipparchus (Bc. , 150) and Ptolemy (150 AD.), to name but two, both employed a system of latitude and longitude to locate stars on the celestial sphere. The Greeks even employed a system that made use of two axes at a right angle. However, nothing systematic or permanent came out of the study of specific problems using two axes as part of the solution. Heath says that ‘the essential difference between t he Greek and modern method is that the Greeks did not direct their efforts to making the fixed lines of a figure as few as possible, but rather to expressing their equations between areas in as short and simple a form as possible. The first real development of a geometrical coordinate system comes in the work of Apollonios of Perga Apollonios of Perga, or the ‘Great Geometer’ as he was known, wrote a book called Conics, which, among other things, introduced the world to the terms parabola, ellipse, and hyperbola. In his Conics, Apollonius used a system of coordinates to solve problems regarding second-order curves (conic sections). The next person significantly to advance the creation of the coordinate system was Frangois Vihte (1540-1603). In his In Artem analyticem Isagoge (Introduction to the Analytical Art) published in 1591, Vihte announced a program to ‘[bring] together the ancient geometrical methods of Euclid, Archimedes, Apollonius, and Pappus, with ancient algebraic methods to produce his logistica speciosa, a way to formulate and solve algebraic problems. Among other things, this text uses consonants to represent given quantities and vowels to denote unknown quantities. This led to Vihte's nickname, The father of modern algebra. The degree of Descartes' originality remains a subject of controversy, as will be addressed at greater length below, a controversy that has persisted in the three and some half centuries since his death.

In Descartes' La Géomitrie, he uses the letters ‘a’, ‘b’, ‘c’, etc., to express of the acknowledged magnitudes and ‘x’, ‘y’, ‘z’, for unknown ones. Later on, Descartes unveils what appears to be the birth of a fixed set of coordinate systems in a passage beginning, ‘Let AB, AD, EF, GH, . . . be any number of straight lines given in position . . . Smith points out here ‘it should be noted that these lines are given in position but not in length. They thus become lines of reference or coordinate axes, and accordingly they play a very important part in the development of analytic geometry. In this connection we may quote as follows: 'Among the predecessors of Descartes we reckon, besides Apollonius, especially Vihte, Oresme, Cavalieri, Roberval, and Fermat, the last the most distinguished in the field; yet, it seems that there may be not anywhere, even by Fermat, had any attempt been made to refer several curves of different or de-simultaneously to one system of coordinates, which at most possessed special significance for one of the curves. It is exactly this thing that Descartes systematically accomplished. However, Scott does not agree with this assessment, as will be seen below. Another person who played a key role in the creation of analytic geometry was Pierre Fermat (1601 -1665), although it is unclear whether or not Descartes knew of Fermat's work (the subject for which we will return), Ad Locos Planos et Solidos Isagoge. In an effort to recover some of the lost proofs of Apollonius, Fermat used a system of coordinates to refer to various curves. There was a large advance in the use of the coordinate system between Apollonios and Fermat. ‘In [Fermat's] published works, too, there is incontrovertible evidence that he had hit upon the idea of expressing the nature of curves by means of algebraic equations. How clearly in fact, he had grasped the fundamental principles of analytic geometry becomes evident after a study of the opening pages of the Isagoge, the substance of which is as follows: 'Whenever two unknown quantities are found in a final equation we have a locus and the extremity of one of them describes a right angle line or a curve.

The straight line is simple and unique; the curves are infinite in number and embrace the circle, parabola, ellipse, etc. . . . Fermat goes on to list various equations of geometric interest, such as the equation of a straight line through the origin (x/y = b/d), the equation of any straight line (b/s = (a-x)/y), the equation of certain types of circle (a2-x2=y2), the equation of certain types of ellipse (a2-x2=ky2), and the equations of certain types of hyperbola (a2+x2=ky2). These formulas should leave no doubt that Fermat understood the underlying principles of analytical geometry, and helped lay the foundation for its development. The ideas with which La Géomitrie had to deal, at least potentially, were of three types according to the formulation of J.F. Scott. (1) The employment of coordinates as a mere instrument of description (2). Algebra and geometry collaborate on single problems (3). Transference of system and structure by analysing these individually we can see how influential they were in the development of analytic geometry, and consider more carefully which of them are actually attributable to Descartes, according to Scott. The first item, according to Scott, constitutes the most visible connection between Descartes' work and the Cartesian plane. In La Géomitrie, Descartes uses a system of coordinates adapted to each problem. When studying multiple curves, he uses a system of lines to unify all the separate coordinate systems into one giant system. This account clashes with the opinion of Fink and Smith, according to whom Descartes' coordinate system was set up in advance for a general set of curves, not a particular one. As far as the second point, it is the most important in Descartes' work. Using algebra to solve geometric problems greatly enhanced the flexibility of geometry. This became a legitimate way to solve a problem, and as is often found in mathematics, the m ore ways there are to approach a class of problems, the better. An example of this given at the outset in La Géomitrie was the solution of a problem of Pappus, which Descartes claimed had not been completely solved by anyone.

In a letter to his friend Mersenne, Descartes wrote, ‘J'risous un e question qui par le timoignage de Pappus n', estre trouvie par qucun des Ancient, et l'on peut dire qu'elle ne l'a p estre non plus par aucun des Modernes.’ (‘I solve a problem that defeated the ancients and the moderns alike.’) Pappus' problem reads, ‘There being three, or four, or a greater number of right lines given in position in a plane, it is first required to find the position of a point from which we can draw as many other right lines, one to each of the given lines, making a known angle with it, such that the rectangle contained by two of these drawn from this point has a given proportion either to the square on the third, if there are only three, or to the rectangle contained by the other two, if there are four. Or if there are five, the product of the remaining two lines so drawn has a given proportion to the product of the remaining two and another line, and so on.’.

Descartes originally attempted to solve this problem using pure geometry, and was unable to. This aided Descartes in his pursuit to find another method to solve the problem. Using his newly developed analytic methods, Descartes wrote in a letter to his friend that he was able to solve the problem in just five or six weeks. Unsurprisingly, Sir Isaac Newton was the first one to solve these problem using methods of pure geometry. As to the third point that Scott raises in regard to the major achievements in La Géomitrie, it appears to be rather similar to the second, and possibly not necessary. As Scott puts it, ‘The structure of a whole region of geometrical theory is transferred to a region of algebraical theory, where it brings about an instructive rearrangement of the matter and raises algebraical problems that otherwise might not have imposed them.’

Among the achievements of La Géomitrie, there are many methods that are still used today. Descartes proposes a method of simultaneously handling several unknown quantities at once. Also introduced is a clearer distinction between real and imaginary root s, which helped lead to modern mathematics. Scott also says, ‘It is momentously liberated, as when Descartes throws aside the dimensional restrictions of [Vihte] and lets the arithmetical second power a2 measure a length as well as an actual square, and the arithmetical first power a measure a square as well as an actual length.’

In La Géomitrie, Descartes views curves of degree 2n and 2n-1 as having the same complexity, and thus as closely related. Scott even claims, Descartes notes, that this number is independent to the choice of organic coordinates. In modern ordinary language it is an invariant under change of axes. Here is a first case of invariance, when employing coordinates we are forced to make an arbitrary choice of axes and even of the type of coordinates, and in this way we impart an arbitrary element into our methods. Scott summarized the work of Descartes in of the priorates stating that what is done by a summarized mark of four mindfully employed headings: (1) He makes the first step toward a theory of invariants, which at later stages derelativises the system of reference and removes its arbitrariness. (2) Algebra makes it possible to recognize the typical problems in geometry and to bring together problems that in geometrical dress would not appear to be related at all. (3) Algebra imports into geometry the most natural principles of division and the most natural hierarchy of method. (4) Not only can questions of solvability and geometrical possibility be decided elegantly, quickly and fully from the parallel algebra, without it they cannot be decided at all. Much of the work that is thus accredited to René Descartes is the subject of controversy. His reputation came under attack while he was alive, attacks that have been renewed in the 350 years since his death. Even at the time of his publication of La Giomitrie, Descartes was forced to defend himself against claims that the work was in large part derived from the work of Pierre de Fermat and Frangois Vihte.

There is no doubt that Fermat compiled his work in 1629, eight years before Descartes published La Géomitrie. However, this work of Fermat did not appear in print until 1679 (posthumously, in Opera Varia), approximately thirty years after Descartes' death. The question then is whether or not Descartes had access to his fellow countryman's compilation before it being published. Fermat gave his papers to M. Despagnet around 1629, but it is unclear whether or not Despagnet circulated these works further. Descartes did not remain silent about such allegations. He vehemently defended himself, saying even that he had nothing to learn from his contemporary mathematicians, because they were unable to solve the ancient problems. And in particular he [Descartes] leaves his readers in no doubt that he did not rate the achievements of Fermat very highly.’

One may wonder whether maybe the opposite was true: could Fermat have ‘borrowed’ from Descartes? This possibility can be excluded. According to Scott, who appears to be a partisan of Descartes, Fermat's letters revealed his character to be of the highest moral caliber. One may also argue that had Fermat been familiar with Descartes' work. He would likely have adopted Descartes' notation, far superior to his own. There is in any case no evidence that Fermat ever saw Descartes' work before its publication, much less before his own work in 1629, nor were any such allegations ever made. Scott comes to the conclusion that ‘It seems possible, therefore, that Descartes and Fermat had each made considerable progress in the new methods unconscious of what had been achieved by the other. He asserts that history has numerous examples of discoveries of great importance that were made simultaneously and independently. Frangois Vihte was another mathematician whom Descartes has been accused of robbing. In Vihte's book called, In Artem analyticem Isagoge, (1591), he uses a notational system to represent algebraic equations similar to the one employed by Descartes in La Géomitrie. T his has led to speculation that much of Descartes' accomplishments were merely restatements of work Vihte had done 45 years earlier. ‘But Descartes' clumsy cosec notation, derived in all probability from Clavius' (a 16th and 17th century teacher at the Jesuit Collegio Romano in Rome) Algebra, which he had studied while in college, indicates that he was not familiar with Vihte's work at this point, for Vihte's notation is clearly superior, and had he been familiar with it he could not have favoured that of Clavius. Descartes was obliged to rediscover these relations, to formulate the problems in his own terms, and to develop his own uniformity implied through the so-called I-ness, that he had only of himself to cause in solving the problem, something he was to do in a way that went far beyond Vihte's pioneering work. On the other hand, had Descartes wanted to take credit for another's ideas, it is doubtful that he would have been so overt as blatantly to copy Vihte's notation. In this regard, Descartes wrote, ‘As to the suggestion that what I have written could easily have been gotten from Vihte, the very fact that my treatise is hard to understand is due to my attempt to put nothing in it that I believed to be known by either him or anyone else . . . I begin the rules of my algebra with what Vihte wrote at the very end of his book, De emendatione aequationum . . . This does of course openly acknowledge familiarity with Vihte.

One final person declared Descartes, which on no any uncertain terms are thought of a plagiarist -John Wallis (1616-1703). Wallis repeatedly and very publicly said that the main principles of coordinate geometry had already been published in Artis Analyticf Praxis by Thom as Harriot (1560-1621). Wallis wrote in Algebra (1685), a treatise designed to promote the ideas of Harriot, which were first published in 1631, that ‘Harriot hath laid the foundation on which Des Cartes hath built the greatest part of his Algebra or Geometry.’

‘While there appears little doubt that Descartes did not hesitate to avail himself of the knowledge of Harriot in his treatment of equations, it is difficult to find anything in Harriot's published works to suggest that he had devoted any attention to the subject of coordinate geometry.’

How René Descartes came up with the ideas, presented in his La Géomitrie is unclear. What is clear is that regardless of the source of these ideas, La Géomitrie is a work of great importance that fuelled the adoption of the Cartesian plane and the development of analytic geometry, allowing problems of geometry to be solved by algebraic methods.

It seems only fitting to end this paper, but the way Descartes ended his La Géomitrie -with a little humour and more than a little arrogance. ‘Et i'espere que nos neueux me sgauront gri, non seulement des choses que iay icy expliquies; mais aussy de celes que iay omises volontairemen [sic], affin de leur laisser le plaisir de les inuenter.’ Or as David Eugene Smith and Marcia L. Latham have it: ‘I hope that posterity will judge me kindly, not only as to the things that I have explained, but also as to those that I have intentionally omitted so as to leave to others the pleasure of discovery.’

‘I do not believe that there exists anything in external bodies for exciting tastes, smells, and sounds, etc. except size, shape, quantity, and motion.’ When Galileo proposed his doctrine of subjectivity and objectivity, as their distinction between primary and secondary qualities, was established by scientific prejudgement, in that the conceptual representation be of space, it was something geometrical and not differentiated qualitatively.

Newtonian ‘absolute space’ was based on a realist conception of mathematics. To Newton, mathematics, particularly geometry, is not a purely hypothetical system of propositions . . . instead geometry is nothing but a special branch of mechanics. Newton's first law of motion, which links change in motion with force requires an absolute (or inertial?) framework. It requires a distinction between absolute motion and relative motion and links force to a change in absolute motion. For example, as the train pulls away from the station, the station may appear to be moving and it can be said that the station is in relative motion to the train, but the force is acting upon the train, and it is the train that is accelerating absolutely. Newton tried to establish an absolute frame of reference for the universe defined in relation to its centre of gravity. (Not necessarily identical with the sun) Absolute spatial movement and position could then be measured in relation to that point.

But is geometry an empirical or ideal activity? For Cassirer, the most radical removal of geometry from experience had already occurred with Euclid, which was already based on figures that are removed from all possibilities of experiment. Not only the idealizations of point, line, and plane, but the idea of similar triangles, whose differences are considered inconsequential or fortunate, and become identified as the same mark, to be as respectably lacking form ordinary perception.

The mathematization of space and its representations in Cartesian grids allowed space to become more abstract and less tied to a specific set of conditions. If the axes of the grid could stand for any set of variables, then a proliferation of types could take place. But even as Descartes' discovery of analytic geometry gave the problem of space an entirely new orientation, his own metaphysics describes space as some sort of absolute thing in the form of an extended substance, not simply a certain pattern of order.

‘In all the history of mathematics there are few events of such immediate and decisive importance for the shaping and development of the problem of knowledge as the discovery of the various forms of non-Euclidean geometry.’ In Euclidean geometry, the axiom of the parallels states that through a given point there is one and only one parallel to a given straight line that does not go through the given point. Non-Euclidean geometry starts with the opposite axiom . . . When Riemann published ‘On the Hypotheses Underlying Geometry’ (1868) the axioms of Euclid, which had been regarded for centuries as the supreme example of eternal truth, now seemed to belong to an entirely different kind of knowledge. For Cassirer, ‘the whole problem of the truth of mathematics, even of the meaning of truth itself, was placed in an entirely new light. Until that time, both rationalist and empiricist philosophers had agreed that the relations of mathematical ideas were rigorously necessary and unalterable. How could entirely different and wholly incongruous systems of geometry uphold the claims of truth? ‘To recognize a plurality of geometries seemed to mean renouncing the unity of reason, which is its intrinsic and distinguishing feature.’

‘Mathematicians appropriated space and time, and made them part of their domain, yet they did so in a rather paradoxical way. They invented spaces: non-Euclidean spaces, curved spaces, – dimensional spaces, abstract spaces (such as phase space), and so on. For example, Gerald Edelman uses the concept of a n-dimensional neural space of all potential qualia, that includes every possible discrimination between states of consciousness. For Edelman, the dimensions of this space are given by the activity of actual groups of neurons in the brain.

In this way, space became a ‘mental thing’ Physicists, according to Rudolf Carnap are free to choose among spatial systems according to their own requirements. He quotes Henri Poincaré's observation that no matter what observational facts are found, the physicist is free to ascribe to physical space any one of the mathematically possible geometrical structures, provided that he makes suitable adjustments in the laws of mechanics and optics and consequently in the rules for measuring. For Poincaré, ‘The object of geometry is the study of a definite group, but the general idea of the group preexists, at least potentially, in our mind, having forced itself not as a form of sensibility but as a form of our understanding. All we have to do is choose among all possible groups the one that will constitute a standard for us, as it were, to which natural phenomena are referred. Experience guides us in this choice but does not dictate it; nor does it permit us to know which geometry is truer but only which is more 'useful.'

Rudolf Carnap rejects Kant's claim that geometry is a priori and synthetic. He splits geometry into mathematical geometry that is a priori because analytic and physical geometry that is synthetic and not a priori. In physics the choice of geometries becomes a pragmatic one. In his Philosophy of Space and Time, Hans Reichenbach develops this empiricist conception of geometry.

Ernst Cassirer shows Poincaré's assessment of the impact of non-Euclidean geometry as a shift in the meaning of mathematical axioms. For Cassirer, the theory of sets had shown that the different geometries were all equally true in an ideal and mathematical sense. Geometry could be defined as a theory of invariants in respect to a certain group -only properties that are characterized by an invariance with respect to certain transformations can be called ‘geometrical.’ While Euclidean geometry applies to a ‘basic set’ of rigid bodies that are freely movable in space without changing form, different transformations can be applied to different sets of objects (defined as the ‘same,’ with respect to a particular criterion) For Cassirer, the modern sense of axioms differs from the ancient. Axioms are no longer assertions about content that have absolute certainty. Rather they are proposals of thought that make it ready for action.

One thing that happened during the Renaissance that was of great importance for the later character of modern philosophy was the birth of modern science. Even as in the Middle Ages philosophy was often thought of as the ‘handmaiden of theology,’ modern philosophers have often thought of their discipline as little more than the ‘handmaiden of science.’ Even for those who haven't thought that, the shadow of science, its spectacular success and its influence on modern life and history, have been hard to ignore.

For a long time, philosophers as diverse as David Hume, Karl Marx, and Edmund Husserl have seen the value of their in work in the claim that they were making philosophy ‘scientific.’ Those claims should have ended with Immanuel Kant (1724-1804), who for the first time clearly provided a distinction between the issues that science could deal with and those that it couldn't, but since Kant's theory could not be demonstrated the same way as a scientific theory, the spell of science, even if it is only through pseudo-science, continues.

The word ‘science’ itself is simply the Latin word for knowledge: scientia. Until the 1840's what we now call science was ‘natural philosophy,’ so that even Isaac Newton's great book on motion and gravity, published in 1687, was The Mathematical Principles of Natural Philosophy (Principia Mathematica Philosophiae Naturalis). Newton was, to himself and his contemporaries, a ‘philosopher.’ In a letter to the English chemist Joseph Priestley written in 1800, Thomas Jefferson lists the ‘sciences’ that interest him as, ‘botany, chemistry, zoology, anatomy, surgery, medicine, natural philosophy [this probably means physics], agriculture, mathematics, astronomy, geography, politics, commerce, history, ethics, law, arts, fine arts.’ The list begins on familiar enough terms, but we hardly think of history, ethics, or the fine arts as ‘sciences’ anymore. Jefferson simply uses to the term to mean ‘disciplines of knowledge.’

Something new was happening in natural philosophy, however, and it was called the nova scientia, the ‘new’ knowledge. It began with Mikolaj Kopernik (1473-1543), whom of which has in being born to a Polish name given to us in calling him Latinized to Nicolaus Copernicus. To ancient and mediaeval astronomers the only acceptable theory about the universe came to be that of egocentrism, that the Earth is the centre of the universe, with the sun, moon, planets, and stars moving around it. But astronomers needed to explain a couple of things: why Mercury and Venus never moved very far away from the sun--they are only visible a short time after sunset or before sunrise--and why Mars, Jupiter, and Saturn sometimes stop and move backwards for a while (retrograde motion) before resuming their forward motion. Believing that the heavens were perfect, everyone wanted motion there to be regular, uniform, and circular. The system of explaining the motion of the heavenly bodies using uniform and circular orbits was perfected by Claudius Ptolemy, who lived in Egypt probably during the reign of the Emperor Marcus Aurelius (161-180). His book, still known by its Arabic title, the Almagest (from Greek Tò Mégiston, ‘The Greatest’), explains that the planets are fixed to small circular orbits (epicycles) which they are fixed to the main orbits. With the epicycles moving one way and the main orbits the other, the right combination of orbits and speeds can reproduce the motion of the planets as we see them. The only problem is that the system is complicated. It takes something like 27 orbits and epicycles to explain the motion of five planets, the sun, and the moon. This is called the Ptolemaic system of astronomy.

Copernicus noticed that it would make things much simpler (Ockham's Razor, that entia non sunt multiplicanda praeter nercessitatem: entities are not to be multiplied beyond necessary: A watchword for many reductionist and nominalistic philosophers) if the sun were the centre of motion rather than the earth. The peculiarities of Mercury and Venus, not explained by Ptolemy, now are explained by the circumstance that the entire orbits of Mercury and Venus are inside the Earth's orbit. They cannot get around behind the Earth to be seen in the night sky. The motion of Mars and the other planets is explained by the circumstance that the inner planets move faster than the outer ones. Mars does not move backwards; it is simply overtaken and passed by the Earth, which makes it look, against the background, as though Mars is moving backwards. Similarly, although it looks like the stars move once around the Earth every day, Copernicus figured that it was just the Earth that was spinning, not the stars. This was the Copernican Revolution. : Now this all seems obvious. But in Copernicus's day the weight of the evidence was against him. The only evidence he had was that his system was simpler. Against him was the prevailing theory of motion. Mediaeval physics had us to believe that motion was caused by ‘impetus.’ Things are naturally at rest. Impetus makes something move, than is less than quantified of some stretchability, leaving out the object to slow and come to rest. Something that continues moving therefore has to keep being pushed, and pushing is something you can feel. (This was even an argument for the existence of God, since something big-like God-had to be pushing to keep the heavens going.) So if the Earth is moving, why don't we feel it? Copernicus could not answer that question. Neither was there an obvious way out of what was actually a brilliant prediction: If the stars did not move, then they could be different distances from the earth. As the earth moved in its orbit, the nearer stars should appear to move back and forth against more distant stars. This is called ‘stellar parallax,’ but unfortunately stellar parallax is so small that it was not observed until 1838. So, at the time, supporters of Copernicus could only contend, lamely, that the stars must all be so distant that their parallax could not be detected. Yeah, sure.

Copernicus was also worried about getting in trouble with the Church. The Protestant Reformation had started in 1517, and the Catholic Church was not in any mood to have any more of its doctrines, even about astronomy, questioned. So Copernicus did not let his book be published until he lay dying.

The answers, the evidence, and the trouble for Copernicus's system came with Galileo Galilei (1564-1642). Galileo is important and famous for three things: (1) Most importantly he applied mathematics to motion. This was the real beginning of modern science. There is no math in Aristotle's Physics. There is nothing but math in modern physics books. Galileo made the change. It is inconceivable now that science could be done any other way. Aristotle had said, simply based on reason, that if one object is heavier than another, it will fall faster. Galileo tried that out and discovered that Aristotle was wrong. Aerodynamics aside, everything falls at the same rate. But then Galileo determined what that rate was by rolling balls down an inclined plane (not by dropping them off the Leaning Tower of Pisa, which is the legend). This required him to distinguish between velocity (e.g., metres per second) and acceleration (change in velocity, e.g., metres per second per second). Gravity produced an acceleration-9.8 metres per second per second. Instantly Galileo had an answer for Copernicus: simple velocity is not felt, only acceleration is. So the earth can be moving without our feeling it. Also, velocity does not change until a force changes it. That is the idea of inertia, which then replaced the old idea of impetus. All this theory was ultimately perfected by Isaac Newton (1642-1727). (2) With the objections to Copernicus's theory removed, the case was completed with positive evidence. Around 1609 it was discovered in the Netherlands that putting two lenses (which had been used since the 13th century as eye glasses) together made distant objects look close. Galileo heard about this and he produced the first astronomical quality telescope. With his telescope he saw several things: (1) the Moon had mountains and valleys. This upset the ancient notion that the heavens, including the Moon, which was completely unlike the Earth. (2) The Planets all showed disks and were not points of light like stars. (3) Jupiter had four moons. This upset the argument, which had been used against Copernicus, that there could only be one centre of motion in the universe. Now there were three (the Sun, Earth, and Jupiter). (4) There were many more stars in the sky than could be seen with the naked eye. The Milky Way, which was always just a glow, was itself composed of stars. And finally (5) Venus went through phases like the Moon. That vindicated Copernicus, for in the Ptolemaic system Venus, moving back and forth at the same distance between the Earth and the Sun, would only go from crescent too crescent. It would mostly have its dark side turned to us. With Copernicus, however, Venus goes around on the other side of the Sun and so, in the distance, would show us a small full face. As it comes around the Sun toward the Earth, we would see it turn into a crescent as the disk grows larger. Those are the phases, from small full too large crescent, that Galileo saw. The only argument that could be used against him was that the telescope must be creating illusions. In fact it was not well understood why a telescope worked. Some people looked at stars and saw two instead of one. That seemed to prove that the telescope was unreliable. Soon it was simply accepted that many stars are double. They still are. (3) With his evidence and his arguments, Galileo was ready to prove the case for Copernican astronomy. He had the support of the greatest living astronomer, Johannes Kepler (1571-1630), but not the Catholic Church. He had been warned once to watch it, but then a friend of his became Pope Urban VIII (1623-1644). The Pope agreed that Galileo could write about both Ptolemaic and Copernican systems, setting out the arguments for each. Galileo wrote A Dialogue on the Two Principal Systems of the World (1632). Unfortunately, the representative of the Ptolemaic system in the dialogue was made to appear foolish, and the Pope thought it was a caricature of himself. Galileo was led before the Inquisition, ‘shown the instruments of torture,’ and invited to recant. He did, but was kept under house arrest for the rest of his life. Nevertheless, it was too late. No serious astronomer could ever be a geocentrist again, and the only discredit fell against the Church.

Descartes is justly regarded as the Father of Modern Philosophy. This is not because of the positive results of his investigations, which were few, but because of the questions that he raised and problems that he created, problems that have still not been answered to everyone's satisfaction: particularly the Problem of Knowledge and the Mind-Body Problem. And in a day when philosophy and science were not distinguished from each other, Descartes was a famous physicist and mathematician as well as a philosopher. Descartes' physics was completely overthrown by that of Newton, so we do not much remember him for that. But Descartes was a great mathematician of enduring importance. He originated analytic geometry, where all of the algebra can be given geometrical expression. Like Galileo combining physics and mathematics, this also combined two things that had previously been apart, arithmetic and geometry. The modern world would not be the same without graphs of equations. Rectangular coordinates for graphing are still called Cartesian coordinates (from Descartes' name: des Cartes). Seeing Descartes as a mathematician explains why he was the kind of philosopher that he was. Now it is hard to reconcile Descartes' status as a scientist and the inspiration he derived from Galileo and others with his clear distrust of experience. Isn't science about experience? We might think so. But the paradox of modern science is its dependence on mathematics. Where does mathematics come from? What makes it true? Many mathematicians will still answer like Plato, but that certainly has little to do with experience. So Descartes belongs to this puzzling, mathematical side of science, not to the side concerned with experience.

Meditations on First Philosophy is representative of his thought. ‘First philosophy’ simply means what is done first in philosophy. The most important thing about Descartes as a philosopher is that ‘first philosophy’ changed because of what he did. What stood first in philosophy since Aristotle was metaphysics. Thus the first question for philosophy to answer was about what is real. That decided, everything else could be done. With such an arrangement we can say that philosophy function with Ontological Priority. In the Meditations we find that questions about knowledge come to the fore. If there are problems about what we can know, then we may not even be able to know what is real. But if questions about knowledge must be settled first, then this establishes Epistemological Priority for philosophy. Indeed, this leads to the creation of the Theory of Knowledge, Epistemology, as a separate discipline within philosophy for the first time. Previously, knowledge had been treated as falling in the domain of Aristotle's logical works (called, as a whole, the Organon), especially the Posterior Analytics. Modern philosophy has been driven by questions about knowledge. It begins with two principal traditions, Continental Rationalism and British Empiricism. The Rationalists, including Descartes, believed that reason was the fundamental source of knowledge. Empiricist’s believed that experience was emptily epistemologically prioritized and seemingly makes possibly of what has in becoming a very common phenomenon, in that of modern philosophy: Denying that metaphysics are possible at all, or become even that metaphysical questions mean anything. That can happen when epistemology draws the limits of knowledge, or the limits of meaning, so tight that metaphysical statements or questions are no longer allowed.

The most important issues get raised in the first three of the six Meditations. In the first meditation Descartes begins to consider what he can know. He applies the special method that he has conceived (about which he had already written the Discourse on Method), known as ‘methodical doubt.’ As applied, methodical doubt has two steps: (1) doubt everything that can be doubted, and (2) don't accept anything as known unless it can be established with absolute certainty. Today Descartes is often faulted for requiring certainty of knowledge. But that was no innovation with him: ever since Plato and Aristotle, knowledge was taken to imply certainty. Anything without certainty would just be opinion, not knowledge. The disenchantment with certainty today has occurred just because it turned out to be so difficult to justify certainty to the rigour that Descartes required. Logically the two parts of methodical doubt are very similar, but in the Meditations they are procedurally different. Doubt does its job in the first meditation. Descartes wonders what he can really know about a piece of matter like a lump of wax. He wonders if he might actually be dreaming instead of sitting by the fireplace. Ultimately he wonders if the God he has always believed in might actually be a malevolent Demon capable of using his omnipotence to deceive us even about our own thoughts or our own existence. Thus, there is nothing in all his experience and knowledge that Descartes cannot call into doubt. The junk of history, all the things he ever thought he had known, gets swept away.

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