Thursday, May 12, 2011

The mind-body difficulty

To: Ian H.
From: Geoffrey Klempner
Subject: The mind-body difficulty
Date: 24 May 2002 13:12

Dear Ian,

Thank you for your e-mail of 14 May, with your latest essay for the Associate Award, 'The Mind-Body Difficulty'.

First, two minor points. The formulation, 'I think therefore I am' actually occurs in Descartes' 'Discourse on Method', although it does not occur in the 'Meditations'. On page 2 you say that, for Descartes, the pineal gland is the place where the soul was 'located'. However, you also correctly observe that the mind/ soul exists in time but not in space. So although its effects are located in space, the soul itself is unlocated.

It is not in fact until Meditation 6 that Descartes gives his argument for mind-body dualism:

"..because I know that all the things I conceive clearly and distinctly can be produced by God precisely as I conceive them, it is sufficient for me to be able to conceive clearly and distinctly one thing without another, to be certain that the one is distinct or different from the other, because they can be placed in existence separately, at least by the omnipotence of God; and it does not matter by what power this separation is made, for me to be obliged to judge them to be different. And therefore, from the mere fact that I know with certainty that I exist, and that I do not observe that any other thing belongs necessarily to my nature or essence except that I am a thinking thing, I rightly conclude that my essence consists in this alone, that I am a thinking thing, or a substance whose whole essence or nature consists in thinking. And although perhaps (or rather as I shall shortly say, certainly,) I have a body to which I am very closely united, nevertheless, because, on the one hand, I have a clear and distinct idea of myself in so far as I am only a thinking and unextended thing, and because, on the other hand I have a distinct idea of the body in so far as it is only an extended thing but which does not think, it is certain that I, that is to say my mind, by which I am what I am, is entirely and truly distinct from by body, and may exist without it."

The key point here is not the appeal to God - which merely illustrates the kind of 'logical possibility' of separation that Descartes has in mind - but rather the move from the conceivability of mind existing apart from body to the conclusion that mind and body cannot be identical. This is known as the 'modal' argument for dualism because it involves the 'modal' ideas of possibility and necessity. If A *is* B, then there is no possible world in which A and B exist as separate entities. Conversely, if A and B *can* exist as separate entities - i.e. if in some possible world A and B exist apart, then A is not B.

How does the beeswax argument, which you refer to, fit in with the proof of mind-body dualism? The key point is that in talking about whether the mind 'can' or 'cannot' exist in the absence of body, Descartes is not talking about what can be imagined, but rather what can be conceived.

My gloss on the significance of the beeswax passage for the above argument would be this: It may well be that we cannot imagine what it would be like for the mind to exist apart from body. In terms of our ability to 'picture' possibilities in the imagination, the world created by an evil demon 'looks' just the same as a world of objects in space. However, Descartes thinks, we are able to conceive of the difference it would make if an evil demon was the cause of our perceptions, rather than objects in space. That is why the argument for dualism depends not on what we can 'imagine' but on what we can 'conceive'.

I think it would help if, armed with a clearer picture of what Descartes is arguing for, you then had a look at a few discussions of the mind-body problem. Dennett's book 'Consciousness Explained' would be a good thing to read. Nagel's 'The View From Nowhere' is also well worth having a look at.

As it stands, the structure and aims of your essay are unclear. You discuss several positions without giving the reader any clear idea of what they entail or how they are related to one another. What exactly is the 'identity theory' and how does it differ from functionalism? What is the 'more cognitive view of the mind...that predominates today'?

It is quite a task to describe all the different theories and approaches. Which is why you should consider narrowing down the focus of the essay.

For example, you could look at the question of mind-body interaction. The metaphysical problem of how mental substance interacts with physical substance gave rise to a number of alternative 'dualist' theories: occasionalism, parallelism, pre-established harmony, and epiphenomenalism. However, even within a materialist (material monist) framework, the problem of the causal relations between 'mind' and 'body' reappears in the form of the question how we are to construe the causal relationships between statements describing the brain on the physical level, and statements of 'folk psychology', i.e. describing the things we think and believe, perceive, feel etc. Thus, contemporary writers use the term 'epiphenomenalism' to refer to a version of materialism, by contrast with epiphenomenal dualism, which holds that mental states exist purely as non-physical by-products of physical processes.

Or, alternatively, you could focus on the challenge posed for materialism by the 'problem of consciousness'. Here, the core of the debate concerns the idea of 'qualia', which you refer to towards the end of your essay.

All the best,