Descartes: As the Creator of Philosophy of Mind – A Critical Estimate of Rene Descartes’ Philosophy of mind-body Relations

Dr. Pushpa Rani Prasad

Abstract

The issue of mind-body relation is as old as the history of Ancient Greek Philosophy. The mind and body share a definite relationship with each other. The problem lies with determining what kind of relationship they share. Evidence indicates that mental events occur as a result of physical neural processes and also, we take it for granted that mental events have physical effects i.e. our perception and desire manage to move our bodily parts. There is no settled agreement on the exact nature of the relationship between mental and physical properties. There are two major schools that have tried to resolve the mind-body problem. These are dualism and monism.

Dualism can be traced back to Plato & Aristotle, but it was most precisely formulated by Rene Descartes. That is why he is often called the creator of philosophy of mind. Descartes claims that mind and body exist as two distinct substances. According to Descartes, minds and bodies causally influence each other. Descartes favors a Divine interpretation of mind-body interaction. Philosophers who advocate monism believe that mind and body are not ontologically distinct kind of entities. Many philosophers have criticized Descartes’ dualism. Ryle has challenged the traditional distinction between mind and body as formulated by Descartes. In his view the facts of consciousness can be linked to the brain. Jaegwon Kim has formulated a ‘real argument’ against the Decartes’ dualism. Kim’s argument shows that immaterial minds cannot causally interact with material things situated in space. I have tried my best to throw light and examine all these aspects in this paper.

Rene Descartes’ Philosophy of Mind-body Relations

The dualist view of persons that Descartes defended is a form of substance dualism. Substance dualism is the thesis that there are substances of two fundamentally distinct kinds in this world, namely minds and bodies-or mental stuff and material stuff- and that a human person is a composite entity consisting of a mind and body, each of which is an entity in its own right. Traditionally, two ideas have been closely associated with the concept of a substance. First, a substance is something in which properties ‘inhere’. Second, a substance is thought to be something that has the capacity for independent existence.

In Descartes’ opinion nature of mind is completely different from that of a body. Mind is a thinking, non-extended thing and body is an extended, non-thinking thing. Since their nature is different, it is possible for one to exist without the other. Descartes has given several arguments in support of his dualistic view. But these arguments are different versions of one and the same argument.

One of his arguments in support of his dualistic view may be formulated in the following way:

1.             I have a clear and distinct idea of the mind as a thinking, non-extended thing.

2.             I have a clear and distinct idea of the body as an extended, non-thinking thing.

3.             Therefore, the mind is really distinct from the body and can exist without it.

Descartes’ above argument is based on his doctrine of clear and distinct ideas. In his work ‘Principles of Philosophy’ Descartes states that a sharp intellectual focus is like a sharply focused visual perception of something, and an idea is clear when it is in sharp intellectual focus. But an idea is distinct when, in addition to be clear, all other ideas not belonging to it are completely excluded from it.

It is clear from the above argument that Descartes clearly and distinctly perceives the mind as possibly existing all by itself, and the body as possibly existing all by itself. There is no doubt that non-thinking bodies like stones, woods exist without minds. This supports his second premise i.e. ‘body as possibly existing all by itself’. But there is no settled agreement among philosophers in respect of his first premise i.e. mind as possibly existing by itself. Many philosophers doubt that minds can exist without bodies. In Descartes’ view the guarantee for the truth of whatever is clearly and distinctly understood is based on the thesis that God exists and he cannot be a deceiver. Descartes claims that clear and distinct ideas are true because if God put a false clear and distinct idea in him, then God would be the source of error and world be a deceiver. In Descartes’ view, he has already established God’s inability to deceive. So, God cannot be deceiver and hence, all clear and distinct ideas must be true.

Descartes has also given another argument in support of his dualistic view. In the Sixth Meditation, Descartes does not support his dualistic view on the basis of clear and distinct understanding of minds and bodies but instead makes his point based on particular property of each. Descartes argues that the mind is indivisible by its very nature and the body is divisible by its very nature. The property of mind is that it is a thinking thing and it is indivisible while the property of a body is that it is an extended thing and it is divisible. For example, we can break a body into several parts. But we cannot divide a mind into two minds because this division of mind would result in two selves, which is absurd. So, the nature of mind and body is completely different. The conclusion is that they are two really distinct substances.

There are also some other arguments that apparently favor the dualist thesis that minds are distinct from bodies. There is a metaphysical argument which favor substance dualism. This argument may be formulated as under:

·        Thoughts and consciousness exist.

·        Hence, there must be objects, or substances, to which thoughts and consciousness occur- that is things- that think and are conscious.

·        Thoughts and consciousness cannot occur to material things, they cannot be states of material objects, like the brain.

·        Hence, thoughts and consciousness must occur to immaterial things, like Cartesian mental substances.

·        Hence, mental substances exist and they are the things that think and are conscious, and bear other mental properties.

In the third premise it is clearly mentioned that material things, like the human brain, are unfit to serve as bears of thoughts and consciousness. For example, numbers like three or four are not the sort of thing that can have colors like blue or occupy a location in space. So, in the same way, there is an essential incongruity between mental states, like thoughts and consciousness on one hand and material things on the other, so that the former cannot inhere in, occur to the latter, just as weight and color cannot inhere in numbers. If our thoughts and consciousness cannot occur to anything material, including our brains, then they must occur to immaterial things, or Cartesians minds.

Leibniz has given an argument to show that thoughts or other mental states cannot occur to material things. Giving an example of a mill, Leibniz states that a mechanical system in which the parts causally interact with another (pieces pushing one against the other), it is not possible to see anything in this picture that would account for the presence of thought or consciousness.

Thus, even if a more complex biological system like human brain replaces Leibnitz’s mill, we find that there is an assemblage of microscopic material things, molecules and atoms and particles interacting with one another according with laws of chemistry and physics. Nowhere in this picture, do we see a thought or perception or consciousness.

These questions are helpful in clarifying dualistic views but it is not easy to understand how thoughts and consciousness can arise in an immaterial substance such as mind with no constituent parts.

Descartes’ Mind-body Interaction

According to Descartes, minds and bodies causally influence each other. In voluntary action, the minds volition causes our limbs to move; in perception, physical stimuli impinging on sensory receptors cause perceptual experiences in the mind. Our minds, in virtue of having certain desires beliefs and intentions, are able to cause our bodies to move in appropriate ways. In the Sixth Meditation, Descartes says about how mental causation works. He writes:

“The mind is not immediately affected by all parts of the body, but only by the brain, or perhaps just by one small part of the brain. Every time this part of the brain is in a given state, it presents the same signals to the mind, even though the other parts of the body may be in a different condition at that time. For example, when the nerves in the foot are set in motion in a violent and unusual manner, this motion, by way of the spinal cord, reaches the inner parts of the brain, and these gives the mind its signal for having a certain sensation, namely the sensation of pain as occurring in the foot. This stimulates the mind to do its best to get rid of the cause of the pain, which it takes to be harmful to the foot.”¹

In the Passions of the Soul, Descartes identifies the pineal gland as the seat of the soul, the locus of direct mind-body interaction. This gland, Descartes maintains, can be moved directly by the soul, thereby moving the animal spirit (bodily fluids in the nerves), which then transmit causal influence on appropriate parts of the body.

In the case of physical-to-mental causation, this process is reversed. Disturbances in the animal spirits surrounding the pineal gland make the gland move, which in turn causes the mind to experience appropriate sensations and perceptions. For Descartes, then, each of us as an embodied human person is a ‘Union’ or ‘intermingling’ of a mind and a body in direct causal interaction.

Critical Estimate of Descartes’ Dualism

Princess Elizabeth of Bohemia challenged the above view of Descartes and asked him to explain how the mind of human being, being only a thinking substance, can determine the bodily spirits in producing bodily actions. According to her, all determination of movement is produced by the pushing of the thing being moved, by the manner in which it is pushed by that which moves it. And for this contact is a necessary factor. Bodies can be moved only by contact. So, her question is that ‘how could a non-extended mind, which is not even in space come into contact with an extended material thing, even the finest and lightest particles in animal spirits, thereby, causing it to move? This is a perfectly reasonable question. We know that to move a physical object or cause any change in any object, there must be a flow of energy from the cause to the physical object. But how could there be an energy flow from an immaterial mind to a material thing. If an object is going to impart momentum to another, it must have mass and velocity. A non-extend mind outside physical space has neither mass or velocity. Descartes’ answer to the above objection is that the idea of mind-body union is a ‘primitive’ notion – a fundamental notion that is intelligible in its own right and cannot be explained in terms of the more basic notions – and that the idea of mind-body causation depends on that of mind body union.

Anthony Kenny has also criticized the Cartesian interaction. In his book ‘Descartes’, Kenny writes that Cartesian minds and physical objects are radically “diverse categories” and this fact undermines the possibility of causal interaction between the two.

Jaegwon Kim has formulated a ‘real argument’ against Cartesian dualism. This ‘real argument’ relates to pairing problem. Kim’s argument shows that immaterial minds cannot causally interact with material things situated in space. He has given an example of physical causation. A Gun, call it A, is fired, and this causes the death of a person X. Another Gun B, is fired at the same time, and this results in the death of another person Y. What makes it the case that firing of A caused X’s death and firing of B caused Y’s death, and not the other ways around? That is why did A’s firing not cause Y’s death and B’s firing not cause X’s death? Kim’s point of view is that there must be a relation R that grounds and explains the cause-effect pairing, a relation that holds between A’s firing and X’s death and also between B’s firing and Y’s death. According to Kim, spatial relations and more broadly, spatiotemporal relations – are the only way of generating pairing relations. It may be said here that Gun A was near to person X and directed towards X whereas Gun B was far away to exert any influence on X. It was because of this relation that Gun A caused the death of X.

As regards the possibility of immaterial souls, outside physical space, causally interacting with material objects in space, Kim’s view is that souls, as immaterial substances, are outside physical space and so cannot bear spatial relations to anything. It is not possible to invoke spatial relations to ground the pairing. The soul cannot be any ‘nearer’ to, or ‘more properly oriented’ toward, one physical object than another. Thus, Kim’s argument relating to pairing problem makes the idea of interaction between immaterial substance like mind and material objects like body, a dubious proposition.

Descartes called the pineal gland the “seat of the soul” presumably because it is the pineal gland where mind-body causal interaction was supposed to take place. But in my view, there is no evidence that there is any single place in the brain – a dimensionless point where mind-body interaction could take place. We know that various mental states and activities are distributed over the entire brain and nervous system, and it does not make scientific sense to think as Descartes did in regard to pineal gland, that there is a single identifiable organ responsible for all mind-body causal interactions.

Many contemporary philosophers are of the view that the concept of mind as immaterial substance is fraught with too many difficulties. Gilbert Ryle in his book ‘The Concept of Mind’ has challenged the traditional distinction between mind and body as formulated by Rene Descartes. Ryle is not in favor of dualism. In his view the fact of consciousness can be linked to the brain. He stresses that Descartes has made a ‘category mistake’. In his view, Descartes represents the fact of mental life as if they belong to one logical category, where in the actual sense they belong to another. He misrepresents the substance responsible for conscious activities.

It appears to me that the root of the problem is the issue of consciousness. Diametrically opposite views have been expressed by the philosophers on the issue of consciousness. J. Nagal writes:

“When the problem of consciousness is solved, the mind-body problem will be solved.”² Reubel Abel also stresses that the “mind-body problem exists because the state of consciousness interacts with the state of corporeal body.”³

Daniel C. Dennett, well-known for his work on consciousness, declares:

“I want to make it just as uncomfortable for anyone to talk of qualia or ‘raw feels’ or ‘phenomenal properties’ or ‘qualitative and intrinsic properties’ or the ‘qualitative character’ of experience with the presumption that they, and everyone else, knows what they are talking about. Far better, tactically, to declare that there simply are no qualia at all.”⁴

Dennett does not deny the existence of all conscious states, but only those with intrinsic qualitative properties or ‘qualia’ like the painfulness of pains and the green of a visual percept. Another philosopher of mind, Georges Ray, has rejected all forms of consciousness, not just qualitative consciousness. The idea seems to be that consciousness has no role to play in a scientific account of human mentality and that in consequence it is wholly dispensable; its existence has no purpose to serve.

Some philosophers and scientists have taken a positive and optimistic stance about the possibility of a scientific account of consciousness. Francis Crick, a Nobel prize winning molecular geneticist, has remarked that “it is hopeless to try to solve the problem of consciousness by general philosophical arguments”.⁵ In his view new experiments that might throw light on these problems are needed.

From the above discussions and views of the eminent philosophers and scientists, it is clear that the mind-body problem ultimately comes down to understanding how our conscious life is related to the biological physical processes going on in our brain. There is no doubt that the conscious state depends on, or arise from physicochemical processes in brain. But how did the electro-chemical processes in the grey matter of the brain give rise to our awareness of colors, shapes, smells and other sensory qualities delivering to us a rich kaleidoscopic picture of the world around us? For an interactionist dualist like Descartes the principle mind body problem is the problem of accounting for causal interaction between an immaterial substance and a material one. Physicalists affirm a monism of substance so they are not required to explain the possibility of causal interaction between diverse substances. The nature of their problem is different. Since the physical domain is causally closed, the question arises how can mental properties exert causal influence in the physical world? How can mental event be the cause of physical event? The second problem of the physicalist relates to consciousness. They must explain how can there be such a thing as consciousness in a physical world?

In Jaegwon Kim’s view physicalists, who believe that all mental properties can be reduced to physical ones, face two challenges in respect to the problem of consciousness. The first is the task of closing the explanatory gap between phenomenal consciousness and the physical world. The second challenge is what Kim calls the predictive gap between consciousness and the physical world. Explaining Explanatory gap, Kim states that every mental state has an underlying ‘supervenience base’ in neural states. We may consider pain as an example. According to mind-body supervenience, whenever one is in pain, there is a neural state that is the supervenience base of one’s pain. We may call this neural state N. Thus, whenever N occurs, one experiences pain. But why is it that pain, not itch or tickle, occurs when neural state N occurs? Why does the pain not arise from a different neural state? Here we are asking an explanation of why the pain-N supervenience relation holds. The problem of explanatory gap is that of providing such an explanation. Pain, apparently resists a functional characterization. Pain is a phenomenally conscious event and lies outside the scope of brain science.

But Kim is of the view that to achieve a solution to the above problem and to close the explanatory gap, we must be able to reduce consciousness to neural states, or reductively explain consciousness in terms of neural process.

The second challenge is centered upon what Kim calls the predictive gap, between consciousness and the physical world. Kim writes:

“As the emergentists claimed, it seems possible for us to know all about the physiology of a creature, say Thomas Nagel’s famously inscrutable bats, but have no idea of the qualitative character of its inner experience.”⁶

According to Kim, if the reductive physicalism is true then complete knowledge of physical properties of a creature should suffice for knowledge of mental properties of that creature. Given the fundamental features of a bat, we ought to be able to conclude the nature of any mental features that fly bat might have. Yet this is not the case, instead any prediction that we make about the conscious states of animals are based largely upon observed co-relation between physical sates and conscious ones; in addition to the physical evidence, we may rely upon observed phenomenal evidence as well. So, an adequate reductive physicalist account of the mind, then should be able to close this gap.

In the book, ‘Physicalism or Something Near Enough’, Jaewon Kim has presented an account of the mind according to which most but not all mental properties can be reduced to physical ones via functional definition.

According to Kim, if mental properties can be given functional definitions in terms of the physical domain, then mental causation can be reductively explained. Kim gives an example of a mental property ‘being amused’. Suppose we want to know how it is that our being amused is causally responsible for my laughing. If we define being amused as having some physical property or other that is apt to trigger smiles or laughter then we can construct an explanation in terms of this definition; we need only find the realizers of this causal role and explain how it is that they play the role that they do. In doing so, we will have explained how it is that ‘being amused’ causes laugher. In short, functional definitions allow us to explain the causal relevance of a mental property by appealing to the causal activity of the physical realizers of the functionally reduced mental property.

Finally, functional definitions also allow the physicalist to respond to the predictive problem of consciousness. Functional definitions allow for predictions of unobserved mental states. If pain just means being in a state apt to be caused by tissue damage and apt for causing winces and grows, then we can reasonably conclude that a bat, or a dog, who has experienced tissue damage will also be in pain. If the animal then proceeds to winces and groans, we will have further confirmation of this fact. Given full knowledge of physical states of a creature coupled with functional definitions of all known mental states, we can deduce the mental states of that creature.

If all our mental concepts or properties, could be functionally defined, then the physicalist who invoked such reductions could consider both the problem of mental causation and the problem of consciousness a thing of the past. Unfortunately, as Kim concedes, not all mental concepts can be functionalized. In particular, qualitative mental states, qualia, cannot be given functional definitions. Kim concludes: “Physicalism is not the whole truth, but it is truth near enough and the near enough should be good enough.”⁷

Conclusion

The above discussions conclude my survey of the mind-body problem. We have seen that Descartes is of the view that mind and body are really distinct. The most important part of the component of Descartes’ dualism is the thesis that mind and bodies causally influence each other. Descartes argues that the idea of mind-body union is a ‘primitive’ notion and the idea of mind-body causation depends of that of mind body union.

In favor of philosophers who view that brain is the source of consciousness it may be said that if there is brain damage, consciousness will cease or mental activities will stop. But this is not a conclusive ground to oppose the claim that mind exists. In fact, there is no any empirical proof to substantiate the view that act of consciousness is the activity of the brain. A close examination of brain does not show any sign of conscious events. For example, when we feel pain, a look at the brain does not empirically show us pain. I have also examined ‘functional reduction’ as proposed by Jaegwon Kim. But even Kim concedes that all mental concepts cannot be functionalized. In particular, the qualitative mental states, or qualia, cannot be given functional definition. It is my conclusion that science will in good time unravel all the mystery of consciousness. Patricia S. Churchland is of the view that the scientific approach is in principle capable of explaining consciousness in neural terms as she indicated, it is an empirical question whether this will actually be accomplished. It is my conclusion that effort should be made by scientists to re-investigate the problem of consciousness anew. The problem which we find in Descartes’ philosophy of mind-body interaction has not been fully resolved by the materialist interpretation of personhood.

Reference:

1.    Descartes, Rene: The Philosophical writings of Descartes, Vol.-II, Cottingham Stoothoff and Murdoch Cambridge: Cambridge University Press, 1985,  Page-59-60.

2.      Nagel, J.: ‘What is Like to be a Bat’, In Mortal Questions, New York: Cambridge University Press, 1979, Page-165-166.

3.      Abel, Reubel: Man is the Measure, New York, Free Press, 1976, Page-203.

4.      Dennett Daniel, C.: ‘Quining Qualia’, In Jaegwon Kim’s Book – Philosophy of Mind, West View Press, Page-307

5.      Crick, Francis: The Astonishing Hypothesis, New York, Seribner, 1995, Page-19.

6.      Kim, Jaegwon: ‘Physicalism, or Something Near Enough’, Princeton, Princeton University Press, 2005, Page-94

7.      Kim, Jaegwon: ‘Physicalism, or Something Near Enough’, Princeton, Princeton University Press, 2005, Page-94

Setu, May 2018