Thursday, August 18, 2011

Difficulties for a materialist view of the mind

To: Joanna C.
From: Geoffrey Klempner
Subject: Difficulties for a materialist view of the mind
Date: 24 May 2004 11:06

Dear Joanna,

Thank you for your e-mail of 16 May, with your first essay for the Philosophy of Mind program, in response to the question, 'What difficulties stand in the way of a materialist view of the mind, according to which thoughts, feelings and sensations are ultimately nothing more than processes in the brain?'

You have worked hard here, raising lots of difficulties for the materialist view.

You start off, sensibly, by giving a prima facie reason in favour of materialism. There is an observable correlation between damage to the brain and disturbance of normal mental activity.

I call this 'prima facie' because Descartes held that the brain was a kind of relay mechanism conveying the impulses from a non-physical soul to the 'animal spirits' which move the body. So one might expect to find disturbance in observed mental function if the relay mechanism is damaged.

You go on to ask, 'How do I 'know' my mind if one does not exist?' A materialist will say that mind does exist, because the mind *is* the brain. What the materialist denies is the existence of a non-physical 'mind' in addition to, or separate from the brain. When you are aware of a pain, for example, the object of your awareness - in fact the process of awareness itself - is in fact a physical process, even though you do not realize this.

You make the point that we are aware of many things in introspection that cannot be discovered by looking at the brain. Here, the materialist might respond that this is merely a reflection of the fact that neuroscience is still in its infancy. One day we will be able to 'read' a person's most secret thoughts and feelings with a 'cerebroscope' or brain monitor.

However, an alternative materialist response is to admit that no-one will ever succeed in constructing a cerebroscope. All that shows (this second kind of materialist will say) is that information is encrypted in the brain in a way which is inaccessible to anyone other than the subject whose brain it is.

I wasn't clear about how you intended to relate the dispute between rationalism and empiricism to materialism. A good question to ask is what place is there for Reason in a materialist universe. You can't define reasons or reasoning in purely materialist terms. However, the materialist will reply that the world of reasons and reason giving is a different level of description of the material universe. That is all. The analogy offered is that if you are looking at the world on the level of atoms and molecules, there is no way of explaining why a round peg cannot fit into a square hole. You have to use a different level of description, that of shapes. But no-one would think that the existence of shapes was a problem for materialism.

You also raise the question of 'intuitive knowledge'. We undoubtedly do sense things in a way which cannot be defined or reduced to rules. However, you also suggest an answer: it is a matter of fine 'tuning' of our sensory apparatus, which is more sensitive than anything which technology has so far been able to come up with.

You make a valid point about our knowledge of universals. However, this is not the same as the point about different animal species. You would expect different species to be sensitive to different aspects of the material world, depending on their special needs. But how does one define a concept in material terms? What is the object of my knowledge when I think of the concept of justice, or the number 2?

Another point is that the same feeling in two different people might not produce the 'same brain electrical patterns in the same part of the brain'. This is an important observation which leads to a more sophisticated version of materialism, known as 'functionalism', which you discuss a couple of paragraphs further on. The idea of functionalism is that just as the same 'program' can run on two different computers with different physical architecture, so different brains can realize the same psychological states in different patterns of electrical activity.

As you point out, no-one has yet produced a computer which can understand what it is processing. Functionalists believe (but cannot prove) that it will be possible one day to produce a genuine 'artificial intelligence', one that understands, is self-conscious like us.

On the other hand, the evidence of psychosomatic conditions cuts both ways. A materialist will see this as an argument in favour of materialism rather than against.

I must correct you on the subject of 'ectoplasm'. In the Meditations, Descartes was adamant that the mind is not a 'breath of wind, a vapour' - in other words the mind is not any kind of 'stuff'. Mind does not have any of the characteristics of body. Ectoplasm, as conceived by Spiritualists is located in space and can its movements even be recorded on a photographic plate. Descartes would have laughed at this.

A good start. For the Associate, you need to have a look at contemporary books on philosophy of mind which deal with the subject of materialism. (E.g. one of the books mentioned in my introductory letter.)

All the best,