Monday, October 17, 2011

Difficulties for a materialist view of the mind

To: Denis C.
From: Geoffrey Klempner
Subject: Difficulties for a materialist view of the mind
Date: 9 August 2005 12:44

Dear Denis,

Thank you for your email of 30 July, with your first essay for Pathways Introduction to Philosophy, 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 an interesting take on this. In view of the fact that the human brain is immensely complex, and given our present limited state of knowledge, there is no reason to think that there will be any difficulty in ultimately accounting for the phenomena of consciousness, thoughts and emotions in materialist terms. Even telepathy, you speculate, may eventually be explained as a physical phenomenon.

However, this still leaves various kinds of experiences described as 'supernatural' such as out-of-body experiences, ghostly apparitions, astral projection and precognition. There is also the belief in life-after-death to account for.

You ask, 'Why should a materialist need to take these ideas into account?' A good question.

A hard line materialist will challenge reports of so-called supernatural experiences, and reject any belief in life after death. (Although, interestingly, Daniel Dennett in 'Consciousness Explained' argues that if the human mind is just 'software' running on 'hardware' then it might be possible to upload my brain program onto disc before I die and then download it into a new body - which would be a form of 'immortality'.)

An alternative, less sceptical line would be to admit that there may exist, after all, another realm apart from the material/ physical, which one might call 'non-physical'. However, as you argue, this non-physical world would in effect become part of the 'physical' world, because 'there has to be a transfer of energy between the two worlds for any interaction to occur.'

In other words, someone who argues, on the basis of unexplained phenomena, that there is more to the world than the physical processes we are familiar with may, for all we know, be right.

That would be a form of 'dualism'. My feeling is that the traditional dualist will not be happy with this conclusion. The main sticking point for the traditional dualist is the difficulty in accepting that any physical explanation of consciousness would suffice to show that the self is ultimately part of the physical world, irrespective of what one includes under the label 'physical'.

Imagine a future world where the existence of mind-stuff has been scientifically demonstrated. In addition to protons, neutrons and electrons, a new entity has been discovered, the 'menton'. Mentons are extremely difficult to detect. The main effect which they have on the physical world is via the human brain. However, based on a model of the human brain, menton-detectors have recently been constructed.

Now a new problem appears in the philosophy class room. Instead of the question, 'Am I just protons, neutrons and electrons?', students now ask, 'Am I just protons, neutrons, electrons and mentons'?

Descartes' argument for mind-body dualism (Meditation 6) can be run just as well for a 'physical world' which includes mentons. Even if an evil demon is deceiving me into thinking that a physical world exists, when in fact no physical world exists, I know that I exist. Therefore what 'I' refers to cannot be physical.

According to the epiphenomenalist who rejects Cartesian mind-body interaction (on the grounds that it violates the conservation of energy) there could be an individual physically just like me, but who did not have *this* inside - my 'zombie doppelganger'. The fact that the menton detector is able to prove that my zombie doppelganger has mentons is not sufficient to show that what I have inside - the indescribable quality of consciousness - is present in my doppelganger also.

Another way of expressing the epiphenomenalist's doubts would be to point out that any physical explanation only explains other physical phenomena. An explanation of the brain processes involved in the experience of perceiving a red patch, for example, might account for the experimental subject's utterance, 'I see a red patch', or the subject's ability to pick out red objects from objects of various colours. The explanation can never get to the 'raw feel' itself.

What these - admittedly rather dubious - arguments indicate is that there are some philosophers who are likely to remain sceptical about materialism, even if neuroscience makes great steps forward.

All the best,

Geoffrey