The Quest for Knowledge: A Study of Descartes

Dr Christopher Reynolds

The quest for knowledge remains a perplexing problem. Mankind continues to seek to understand himself and the world around him, and, indeed, how it is he/she can even be certain of the things he thinks he knows. While serious debate of these issues has continued for centuries, mankind seems to be never completely satisfied with the answers. At times, the answer to Douglas Adam’s question; ‘what is the meaning to life the universe and everything?, as ‘42’ can seem as good as any. ( Adams, 1985 p.94) Fundamental to the question of the nature of things, however, is the question of knowledge itself. How do we know what we know? Or how can an epistemology be developed that provides a framework for perception and understanding?

Rene Descartes endeavours to address these questions in his search for knowledge, in the first instance for himself, but as Margaret Wilson suggests, in the hope of also challenging the epistemology of the “... great Aristotelian - Scholastic synthesis that had dominated European thought for centuries.” ( Wilson, 1993 p. xiii.) His essential task was to reconceive a process of discovering knowledge. For Descartes, this meant ridding himself of all prejudice, or prejudgments, and to doubt. To doubt everything. Descartes’ reconstruction of a knowing process was based upon a mathematical approach and gave a physiological answer to his problem. It also led to a revamp of the ancient concept of the mind-body dualism. Descartes must be seen as a great philosopher for his contribution to the historical development of the thinking process and to learning. But his greatness is not to be found in his discourse on the body-mind dualism, his physiological epistemology or even his cartesian doubt. His greatness is found in his contribution to the thinking process itself in the form of analysis and synthesis, as Spinoza suggests, ( Spinoza, p. 3) and his methodological or deductive process of discovering knowledge.

Descartes search for knowledge starts with a claim of doubt. He doubts his senses, his body, everything he has experienced. In claiming doubt as his first step to knowledge, Descartes did not want to become a sceptic and doubt for the sake of doubting. His main intension in starting with doubt was to allow scientific inquiry to begin. In order for Descartes to map out, or set a paradigm for scientific endeavour, clearly a ‘method’ was needed, although the method in itself was not be a complete answer to scepticism but a process by which the reasonable and thinking person could find knowledge. Implicit in Descartes’ aim to map out the physical world is the notion that the epistemology of the Scholastics, had thwarted scientific endeavour. Accordingly, he set out to furnish a method that would provide foundation for a process of knowledge that could not be questioned by the sceptics. Having found a refutable method, Descartes believes this earns him the right to get on with things.

In the first Meditation, doubt is introduced slowly to prepare the thinker and reader for what must come later; complete doubt. At first, Descartes wants the thinker and reader to see that it possible to be in error. Only later in his work does he introduce the reader to the idea that they are always in error. Still, it must be remembered that doubt for Descartes is not a negative thing. His process is not a journey toward nihilism.

Spinoza says that in order to proceed with his investigation Descartes determined to:

“1. To lay aside all prejudice.
2. To find the fundamental truth on which all knowledge rests.
3. To discover the cause of error.
4. To understand everything clearly and distinctly.” ( Spinoza, p.11)

In order to understand things clearly and distinctly his principle rule was to examine everything separately and in its simple form in order to discover how other things are composed. (Spinoza, P.12) This objective was the basis for Descartes’ journey into doubt. He therefore convinced himself that there was nothing in this world that could be automatically accepted as truth, not even his own senses.

Descartes thinks that doubt will move the inquirer toward the elimination of error and, accordingly, certainty will be given to knowledge. Complete doubt, as taken up in the
Second Meditation, places the reader with the question of do I exist? His response is “I think, therefore I am.” Or, “I exist”. Even in doubting, and in considering that in all things he might be deceived, he still thinks and this can not be taken from him. However, human and personal existence is still not a settled matter. He can only be sure of his existence when he thinks. Doubting, then, “... is the foundation on which all knowledge rests.” (Spinoza. p. 13)

Descartes reasoning process was deductive and this ‘cogito’ gives the reader the first principle or certain knowledge: Namely that she exists with a mind though she may still be in error in her judgements. Descartes shows that no “sense experience”, independent concept, or arbitrary judgement can furnish knowledge” other than that which is “clearly and indubitably perceived” by the mind ( Fourth Meditation). Descartes in the first two Meditations is at pains to both define a method and to define what counts as knowledge.

In the Sixth Meditation, Descartes goes on to distinguish between the ‘mind’ and the ‘body’. The point of the dualistic distinction is to build up a knowledge of material things and their existence; they exist in so far as our ideas of them are clear and distinct. The existence of material things depends on their being ‘clearly and distinctly perceived.’ Descartes qualifies his argument by suggesting that no one would seriously doubt their existence. His point is that knowledge of material things is seriously lacking when it is founded on sense experience.

Yet, in asking questions of the physical, Descartes is forced, although seemingly willingly, to ask questions of the metaphysical. His arguments about the existence of material things, he suggests, is not as solid as his reasonings for the existence of God. Indeed, the existence of God becomes one of the basis pillars of his thesis. Descartes claims to be a ‘thinking thing’ and that knowledge is discovered through distinct and clear perceptions. In first presenting a case for the existence of God, Descartes goes on to claim in Meditation Five that God can not deceive the thinker. The thinker, then, is offered a guarantee for the ‘cogito’ (Meditation Three) which sets the boundaries of knowledge. From Meditation Five, he presents the thesis that knowledge must depend upon God. His argument implies that it is now possible to begin to map out the physical universe with mathematical method.

It seems that the most important issue for the thinker is to accept the causal relationship between God’s existence and ‘cognition’s ability to know clearly and distinctly. To decide against Descartes thesis is to make a choice against ‘rationalism’ and for ‘scholasticism’. In general, Descartes rationalism could be reduced to four maxims, as read from his Meditations:

1. Never accept anything as true unless it is clearly and inescapably so.
2. Reduce a problem to the simple or particular
3. Organise particulars into general knowledge
Check for completeness.

It is that doubt is followed by cognition, guaranteed by God, and followed by a mathematical, or material, map of the world.

Still, his approach to be claim ‘objective reality’ (Third Meditation) leads him to address the age old questions of the nature of man (mankind) and the nature of God. While his endeavour to find material answers to physical problems ultimately led him to deal with the metaphysical, so his claim to find ultimate truth in subjective realization leads him into an examination of consciousness and self consciousness. Indeed, it is this awareness of his own consciousness that leads Descartes to believe that he has found the basic principle of knowledge: He knows, or is aware of his own consciousness. This, of course, leads him to question the validity of the knowledge which arises from his unconscious or dreaming mind. Without saying so directly, the conclusion is that the mind can produce both truth and error. For Descartes, the discussion becomes one of the ‘power of understanding’ and the ‘power of imagination’. ( Sixth Meditation)

Descartes metaphysical argument furnishes him with one source of understanding the soul, or mind, as the other source is physics, or the ‘medicine’ that treats ‘the machine of our body’. (Strauss p. 388) While the soul and body form different worlds they nevertheless interact, each effecting the other. The acting of thinking and sensing becomes a process of ‘interaction’. Descartes ‘interactionism’. And so the dualism is set, although the struggle between mind and body is never clearly settled. The “... principle effect of all the passions in men is that they incite and dispose their soul to will the things to which they prepare the body.” (Strauss p. 389) The greatest of the passions for Descartes is seen to be generosity. In all this, however, is Descartes physiological view of the soul.

Still, Descartes epistemology does sit easy and there seems to be a number of problems. It seems that the fundamental flaw to Descartes rationalism is that it arises out of an ontological knowledge, or awareness of being. The only real truth he discovers in realising he is a ‘thing that thinks’ is an ontological truth. That is, he can not confirm someone else’s existence because he thinks, or because they think. His truth then is personal or subjective truth. But at least, it is truth for him.

This, then, leads to the second problem for his rationalism: it appears to be an existential reality. Truth is knowable because he, in the experience of his consciousness, has discovered it. This personal and subjective reality does not lead to the objective reality, or universal reality that he claims. His claim for self realisation, or perhaps, self revelation, proves little to some other self conscious being. To say “I think, therefore, I am’, is not testable or knowable by anybody else. It is an existential reality. It is as though Descartes has established for himself the ‘knowing ego’. ( Strauss p. 388)

Still, it is a curious departure from the Greek understanding of knowing ( gnosis) where information and observable reality is given intellectual assent, to a knowledge that includes an experiential and existential qualification. It raises the question of whether truth and knowledge can be neutral. But more of this later.

Descartes rationalism arises out of a deductive process that incorporates a number of premises:

1. I think therefore I am
2. God exists
3. My mind has clear and distinct ideas
4. God guarantees my clear and distinct ideas
5. I have clear and distinct ideas about a material world.

This rationalism seems problematic in that the logic is not obvious: He moves from a subjective realisation, to a universal truth, to a statement of faith, and then to a objective realisation. While it obviously worked for Descartes, this process of deductive reasoning based on the existence and guarantees of God was not to last. This combination of elements in deductive reasoning was not to be Descartes strength. (Strauss, p.387)

Yet, a criticism of Descartes’ theory of methodological knowledge must also consider his revamp of the body-mind dualism that has come from the Ancients. Again, out of his own consciousness he declares a perception of his own will and passions (Sixth Meditation) and a discovery of the power of the mind and body. But he is not the first by any means to become aware of this struggle of the physical and the intellectual. Niebuhr points out that both Plato and Aristotle share a common rationalism and a common dualism setting the body, or flesh (sarx), over against the rational mind (nous). In the thought of Aristotle, he says, nous is immortal and for Plato, the “immutability of ideas is regarded as proof of the immortality of the soul.” (Niebuhr, p.7). In contrast, the body is identified with evil. The outcome of this dualism is that nous becomes divine, or virtuous, and the body, or flesh (sarx) becomes identified with nature and the forces of nature as evil. Here, then, are the fundamentals to Gnosticism ( gnosis, knowledge).

Of course, these notions stand in contrast to Christian theology and philosophy. As Niebuhr points out, “... the Bible knows nothing of a good mind and an evil body.” (Niebuhr, p.7) This point is made clear in the first chapter of John’s Gospel: “In the beginning was the Word (logos)... and the Word became flesh (sarx).” A concept totally foreign and repugnant to the gnostic and greek classical thinker.

All of this is to point out that Descartes personal indulgences into the body-mind dualism debate is dangerous ground, especially as his quest is for knowledge and the processes of thinking are lifted to virtuous proportions. Still, there is no hint that the body is evil. Only that it is powerful and material. This debate continues as mankind seeks to master nature, and his/her destiny. Under a modern humanistic and capitalist world, mankind appears to have arrived and mastered nature. (Niebuhr, p.20) Indeed, in the modern capitalist world, it is science that has taken the “honoured” position. (Searle, 1984, p. 11)

In review of Descartes personal quest to understand the body-mind dualism, one wonders whether he really moves the debate much further than the classical Greeks. The power to will and the power to understand remain depicted as an active struggle and, like the Greek tragedies, it is a war within and a war with no solution.(Niebuhr, p.11)

While Descartes hoped to challenge and replace scholastic reasoning, the rapid decline of Cartesian metaphysics, Watson believes, was due to epistemological and ontological incoherencies ( Watson, p.21). He says that “... if every cause must be in some way like its effect, then the Cartesian metaphysical system incorporates an unbridgeable gap between mind and matter.” (Watson, p.22) He continues, “ The Cartesians ... could not explain neither how two substances unlike in essence could causally interact nor how one could know the other.” (Watson, p.22)

Watson is also critical of Descartes epistemology, based as it is, on the grounds of doubt. This system, he says, leads to literally knowing nothing, “... neither existence nor essence, not even of himself.” (Watson, p.viii) Descartes is unable to establish epistemological certainty because of the logical ‘incoherencies of his ontological dualism and ... because just as his physics failed to fit the facts of experience and experiment, so also did his theology fail to conform with Christian hopes and dogma. In the end reason fails Descartes.” (Watson, p.ix)

To return to the discussion of Descartes quest for knowledge and basic truths, it was said that his rational process seemed perplexing as he moved from the subjective to the universal to the objective. His rationalism doesn’t seem rational. Perhaps another simpler way of rational construction would be:

1. I can know
2. There is something to know
3. I can use subjective understanding to bridge the gap.

To say ‘we know’, is to say something about observable reality. It seems therefore a contradiction to start with the premise of doubt: To look for what is knowable in what we deny to be known. Descartes may well have said; “I know, and I’m sure I’m wrong”. Or, “I know, I think.” Something of a contradiction in knowledge.

Yet, a further problem, and an essential problem, is the acceptance in all this of the neutrality of knowledge. Knowledge is never free of influence, of history, or experience, of imagination, or context. To say that knowledge is neutral is fiction. Try as he did, Descartes knowledge did not come from nowhere. He was not able to rid himself of all prejudice and his mind was not free from all previous influence. Indeed, knowledge does not proceed on what can be proved before we know anything, or we could know nothing. But knowledge proceeds on what can be presumed. Presumptions come first. This is, then, a condition of faith, even for Descartes ( Guiness p.2) While Descartes attempts to challenge the scholastics, his attempt is to only replace one set of dogma with another. Or one orthodoxy with another. Surely the challenge is to consider orthopraxis as well: To consider practical application and even the responsibility of knowledge. Here lies the basis of an ethical endeavour.

Regardless of the flaws or problems inherent in his epistemology, knowledge as a intellectual property or process does not go far enough. It remains unreal, or unrelated to a real and practical world in need of knowledge as practical knowledge. Knowledge needs to have some sense of ‘do-ability’ about it for knowledge has no virtue of its own. In a similar vein, with the movement of the world into a Third Wave of technology based on information ( Toffler, p.31) the issues of the responsibility and the practicality of knowledge become paramount. Knowledge, Toffier says, will become wealth, and the rich and poor will be redefined. The use and abuse of knowledge becomes the new frontier for philosophy and ethics as knowledge becomes power in a far more powerful way than ever before. But space does not permit a further discussion.

In conclusion, the epistemology and metaphysics of Descartes may be flawed because it does not go far enough or because of the premises of his argument. But his challenge to is to accept deductive reasoning and the process of analysis. Indeed, this is his contribution to social science. At the same time, his discourses of the mind-body dualism and epistemology open the way for so much further reflection about the processes of the mind. Searle points out that the issue of consciousness is to be supplemented by three others which make up the mental phenomena and “... seem impossible to fit into our ‘scientific’ conception of the world as made up of material things.” ( Searle, p.15) These are, ‘intentionality’, ‘subjectivity’, and ‘mental causation’. These features make the mind-body problem difficult. Still, knowledge must be understood as more than a physiological phenomena, It must have a social and even an environmental context as well as an ethical context. Otherwise knowledge is self indulgent and an analgesic. The quest for knowledge must ask questions of consequence. The great “I think therefore I am”, must be followed with a great “So what?”


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