History of Western Philosophy – Research Paper
Do you think that Descartes has satisfactorily solved the problem of mind-body dualism? The Cartesian Dualism has come across three main problems, first, whether Descartes had successfully proven the existence of the non-material thinking soul, second, whether the soul (thought) can interact with our body (extension),
regardless of the truthfulness of dualism, third, and the mental-or-physical dilemma. However, we cannot find any satisfactory and adequate answer of those problems in Descartes’ dualistic philosophy
1. Descartes’ Mind-body Dualism
In Cottingham J, “Cartesian man”, the author began discussing Descartes’ arguments with the comparison between animals, men and machines.
Descartes held that there would still be differences even the machines are made “bore a resemblance to our bodies, and imitated our actions as closely as possible for all practical purposes (p.109).” For machines cannot “produce different arrangements of words so as to give an appropriately meaningful answer to whatever is said in its presence” and they cannot “act through understanding but only from the disposition of their organs (p.109).” That is to say, the difference is that every action or utterance of a machine is limited by environmental conditions; whereas a human can deal with everything in their life freely and creatively because he can “instantaneously interpret an indefinitely large of utterances [situation] (p.110).”
Human being has a unique competence for language, which is distinguished from “utterances of animals” (p.110). Descartes claimed that “utterances of animals” are not regarded as genuine language in that their utterances are just expressions of their passion, such as hope of eating, fear and joy etc.
One may ask why would human being possess such a peculiar ability that even the most sophisticated machine and a magpie (a bird can imitate people talk) would not have. To ask this question, for Descartes, is simply to ask what kind of substance that we human being exclusively own. And he would say it is our rational soul (anima rationalis) contributes to our thinking which allow us to cope with “the indefinitely diverse contingencies of life” (p.109) and be a “genuine language user” (p.109).
Extension, for Descartes, is an underlying substance that contains different attributions an object has, namely weight, colour, hardness, temperature…and the like. Dualists maintain that a human is constituted not only of a bodily substance, but also of a thinking substance (that we have mentioned in above paragraphs). Descartes thought that the latter, which produce a thinking mind for human, should not be derived from extension. It is simply a non-material substance –that has no extension- “specially created” (p.111) and implanted in each of us by God.
Nonetheless, is such a difference adequate for us to ascribe our “thinking feature” (the function of mind is to think) to a non-physical thinking soul? As we know for Descartes the words “mind” and “soul” are of no difference at all. Materialist may argue that the brain alone can produce rational thinking of human. Now let us go over the arguments offered by Descartes attempting to prove the existence of rational soul and examine their successfulness.
2. The Argument from Doubt
To reach the “non-materiality of the mind” (p.112) Descartes had applied his “method of doubt” which is to find out “what cannot be doubted”. Descartes examined his own existence by doubting (imagining the disappearance of) the existence of his own body and the world he was in, until he found himself unable to doubt he was thinking (his mind existed), which assured his existence. Since one could doubt all material things, Descartes believed there were non-material substances distinct from the body giving rise to our thought.
A Descartes’ critic Antoinc Arnauld reckoned that although one can imagine himself without a body, body is “indeed an essential part of him” (p.112), without which one could not even exist. Such a refutation seems to have presupposed a materialistic view, that human’s existence relies on physical substance; and it fails to falsify Cartesian’s argument because Descartes could resist by restating his mind-body dualism, saying the mind could exist alone even though the body is eliminated and immortality is a feature of soul.
However, Descartes himself finally admitted that the argument could not sufficiently and deductively prove the immateriality of soul as the soul could be derived from “our undoubted existence”.
3. The Argument from Clear and Distinct Perception
Descartes stated that if one could “clearly and distinctly understand” one thing apart from another, it was enough to assure him that they were two distinct things owing to their capability of being separated. Therefore, having a clear and distinct idea of myself, to the extent that “I” am simply a thinking, non-extended thing; is separated from having a distinct idea of body, in so far as this is simply and extended, non-thinking thing. In accordance with such distinction, “it is certain I am really distinct from my body and can exist without it (p.113).”
Then he said that the mind and the body were complete ideas that he could conceive them alone respectively. What he wanted to point out was that if one knew that the mind (a complete idea) could exist without the body (another complete idea), then one could know that the body is no part of the mind’s essence (p.114).
The problem here is that even one can clearly and distinctly discern thinking from body; it does not follow that the one who thinks must be non-corporeal. That is to say, although we can directly aware of our thinking, we cannot directly aware of “what (who) does the thinking” (p.115), which can be corporeal.
4. The Divisibility Argument
This argument intended to prove that the mind and the body were two entirely different substances (non-material and material, as mentioned) by saying that mind was indivisible in nature but body was divisible. Moreover, Descartes held that if there was bodily division (e.g. cutting off a hand from a body), “nothing had thereby been taken away from the mind” (p.116). What he meant “nothing” here was simply what he called “pure thought” (to doubt, to understand, to affirm, to deny, to be willing and to be unwilling, p.122), which can “occur without physiological events taking place in the brain or anywhere else” (p.116).
Critic of Descartes suggested that “our desires and our reason could pull us in opposite directions” (p.118) and such “directions” would make our consciousness not simple and indivisible. Dualist could reply that even if there were opposite directions occurring in a consciousness, that “thinking I” could just make one decision, so the mind could retain its unitariness.
Again, the problem of the argument is that we cannot infer a non-corporeal soul from knowing that our consciousness is indivisible, as “what does the thinking” may still be physical.
Hitherto we have not found the arguments above sufficient and satisfactory to prove the immateriality of soul. Now it is time we discovered the problems encountered by Cartesian dualism, suppose the dualistic account is true.
5. The Problem of Interaction between Mind and Body
The most significant problem for dualism is the problem of interaction between mind and body. As we all know mental changes and physical changes can cause one another. Some kind of causal flow from mind to body and vice versa is necessary in order for such things to be possible. However, since mind and body are defined by Descartes in terms of “not just distinct but mutually incompatible attributes”, it is not easy to see how such causal flow is possible (p.119). That is to say, it is difficult to see how the soul can initiate bodily movement.
In spite of this, we are also curious about where the soul is supposed to take place. Descartes thought that it was located in the innermost part of the brain, which is a certain very small gland situated in the middle of the brain’s substance. (p.121) In other words, the point of interaction between soul and body must be within the brain.
He proceeded to say that there must be one place where the dual data from sense organs (eyes and ears etc.), were integrated, so as to enable the soul to have a single (visual or auditory) perception (p.121). Here, the soul was like a little man inside the brain viewing the images from the optic nerves converge.
The fatal problem of the thesis was that the pineal gland is the ‘principal seat’ of the soul only postponed, and did not solve the problem of how psycho-physical interaction is possible.”
6. Sensation and Imagination
There is another difficulty of Descartes mind-body theory namely the mental-or-physical dilemma. It implies that we, human beings, are also dealing with some psycho-physical phenomena which are not categorized as either purely mental or purely physical.
Now it seems that the two categories, mind and body, created by Descartes cannot include all human experience. Let us look at how Descartes pondered on his nature:
But what then am I? A thing that thinks. What is that? A thing that doubts, understands, affirms, denies, is willing, is unwilling and also imagines and has sensory perceptions. (p.122)
We should have no question about the first four activities, they are what Descartes regarded as “pure actions of the soul”; whereas the last two ones, imaginare and sentire, he had a different account on them.
Descartes assured that when one had sense-perception, some actually present external objects printed an idea or a figure of themselves on his senses. These images would then be imprinted on the pineal gland and perceived by the mind; furthermore, when one had imagination, his mind imprinted some images on the gland, fashioned and shaped them in the brain in the absence of external objects. (p.123)
We know from the above that imaginare and sentire are not activities we can practise with our pure intellect (mind) alone. It requires physiological activity which also requires optic and auditory nerves and brain activity, movements in the pineal gland. That is to say, without sensory nerves, we cannot perceive; without pineal gland (brain), we cannot imagine.
One may ask why sensory experience and imagination involve brain activity. Descartes’ answer was that imagination needed a ‘peculiar mental effort’ (p.125): suppose we were conceiving and imagining some geometrical figures, we could conceive a dodecagon rather easily but we would feel strange (confused) when imagining it. So there was always a ‘curious gap’ between our purely intellectual cognition of the figure being considered and our ability to imagine and visualize it (p.125). This sensation of having to wait until one finishes visualizing the figure is exactly the evidence of non-pure-intellectuality of imagination.
On the other hand, sensory experiences, Descartes noted, like hunger and thirst, taught people that they (their souls) were very closely joined or even intermingled with their bodies, so that they and their bodies could form a unit. The soul here, is like “a sailor perceives by sight if anything in his ship is broken. (p.125)” Therefore when their bodies needed food or water, they should have explicit understanding of the fact, that is, they knew they are hungry and they knew they are thirsty.
In addition, Descartes insisted, some sensations, like hunger, could not be clearly and distinctly conceived, they are inherently ‘confused’. So we can see the difference between, on the one hand, doubting, understanding, affirming, denying, is willing, unwilling; on the other hand, imagining and having sensory perception. For the last two ones have an inherently confused, indefinable, subjective quality which requires the hybrid of mind and body.
The dualistic problem here is that both the faculties of imagination and sensation are not straightforwardly ‘mental’, and they are capable of being accommodated with Descartes’ official dualistic schema. Official dualistic schema seems impotent to explain the complex psycho-physical phenomena.
Even Cartesian dualists can reply the question of how psycho-physical interaction is possible by saying the sensation (sense-perception and imagination) is exactly the evidence of the psycho-physical interaction. However it is still inadequate to answer how the mind initiates the bodily action.
Conclusively, Descartes failed to, first, prove the existence of non-material soul; second, he failed handle of the problem of how mind and body interact, and, last but now least, his dualistic theory was unable give an account on the complexity of imagination and sensory perceptions (psycho-physical phenomena).
Cottingham J, “Cartesian Man”, in Descartes, Oxford: Blackwell, 1986, Ch.5