Thursday, September 6, 2012

'Inside' and 'outside' the mind - Descartes' case for dualism

To: Kathleen C.
From: Geoffrey Klempner
Subject: 'Inside' and 'outside' the mind - Descartes' case for dualism
Date: 21 April 2008 12:31

Dear Kay,

Thank you for your email of 10 April, with your second essay for Philosophy of Mind, in response to the question, 'Examine Descartes’ argument in the Sixth Meditation for the distinction between mind and body. What objections can you conceive being raised against the argument? How would you attempt to defend the argument against those objections?', and your email of 15 April resending your first essay which you originally sent (attempted to send) on 26 March, in response to the question, 'Select one line of argument from units 1-3 and express it your own words. (Imagine you are explaining the argument to a friend who knows nothing about philosophy.)'

Inside and outside

It is funny that you should choose this, because (as you realize) the 'argument' in question is in fact not an argument I am putting forward as part of the ongoing inquiry but rather a view or belief -- a 'hypothesis' -- which is being carefully set up for reductio.

The 'inside' is not like this. If it were, one may deduce from the argument, then it would indeed be the case that we could not be sure that we enjoyed qualitatively similar experiences, or indeed that some of 'us' were not in fact behaviorally indistinguishable zombies.

You say, 'Let me offer you one certainty. When I experience looking at blue, I cannot be mistaken. It is logically impossible for me to be wrong. Sadly the certainty doesn't last.'

Wrong about *what* exactly?

Wrong that it is 'blue'? No, because we are not talking about the colour of the sky or blue ink but rather the colour of my private impression, 'the colour that the things you and I call "blue" looks to me'.

In what sense is this a 'colour'? Is there any chance that your friend who knows nothing about philosophy might begin to waver on this point?

There are things I could have said here. For example, one temptation would be to assert that colours are *only* in us. Out there, there are just atoms and molecules, light waves and the laws of physics. The sort of thing Bertrand Russell would say. Naive realism tells us that there are blue 'things'. But, as Russell famously argued, 'Naive realism leads to physics; and physics, if true, shows that naive realism is false. Therefore naive realism is false.'

In other words, philosophical analysis reveals that 'blue' is necessarily a property of sense data, and nothing but sense data.

Wittgenstein, Russell's eager student, saw the fatal flaw in this theory. We have taken a word from its normal context, and applied it in a situation where all the normal criteria for its application have been stripped away. All that is left is the immediate certainty that 'this is this'. The problem is, that we are not content with calling this 'this'. We imagine that we can describe it, relate it to other thises.

Contra Russell, the only truly 'logically proper' name would be one which we applied strictly on one occasion. I put 'S' in my diary once and never again. Nor can I recall the 'meaning' of 'S' because any such mental object is different from the original mental object to which the label 'S' was attached.

Most commentators assume that Wittgenstein denies the existence of the 'private object'. But I wonder whether there might not be another interpretation, whereby the private object, the unnameable, unrecallable 'this' exists all right, only nothing can be said about it. (And a 'nothing would do as well as a something about which nothing can be said.')

Descartes' argument for mind-body dualism

Most commentator's take Descartes' argument in Meditation 6 to involve an implicit recapitulation of his argument in Meditation 1 to the effect that it is logically possible that my mind exists and no body exists. It is strange, however, that he doesn't say so explicitly, but gives the impression that he is relying on an unargued intuition that mind and body may be 'clearly and distinctly' conceived as separate.

One objection you consider is to the effect that different people have different 'clear and distinct' perceptions. You connect this to the argument in Meditation 1 by saying that 'he has told us of an experiment in doubt that he has conducted... there is no guarantee that if we repeat the experiment we will come to the same conclusion.'

How would you defend Descartes against this objection? He wasn't conducting an empirical experiment, Descartes would say, but rather doing a piece of logical analysis. The point of the analysis is to show that there is nothing in the subjective character of conscious experience that 'proves' the existence of physical reality. A subjective experience is what it is and has no implications outside of itself. That is the immediate corollary of the fact that the quality of subjective experience as such cannot be doubted. The evil demon is just thrown in to make the point more vivid.

This is the 'problematic idealism' which Kant approved of because it is phrased in terms of a challenge: a challenge which Kant believed he could meet (in the 'Refutation of Idealism' of the 2nd edition of the Critique of Pure Reason). Kant aside, the point here would be that Descartes is issuing a challenge. To meet the challenge it is not enough to say, 'I performed the experiment and I got a different result!' You have to do a Kant and prove, e.g. that experience is 'only possible on the condition that it is interpreted as experience of an external world'.

Descartes does state at one point that my mind is not lodged in my body as a 'pilot in a ship'. However, he is right in holding that there is no logical inconsistency between this view and his empirical speculation that the pineal gland is the one physical location of the body which is sensitive to changes in a non-physical, non-located soul substance. It isn't an objection that it doesn't *feel* like that. It is indeed a problem for physics (easier to solve in Cartesian physics than in Newtonian) but not a crushing logical objection.

One objection you didn't consider was along the lines of the 'contingent identity' thesis advocated by the 'Australian materialists' Armstrong and Smart. Sure, mind and body *might have* been distinct (in some other possible world) but in fact the best scientific evidence shows that they are not. By Occam's Razor, we should choose the simpler hypothesis -- identity of mental and physical events -- over the more complex.

Kripke's 'Naming and Necessity' which originally appeared in 1972 played a considerable part in reviving the mind-body debate, by arguing that if 'mind' and 'body' are viewed as 'rigid designators', then their identity must be necessary, effectively blowing the contingent identity thesis out of the water. That is why the only effective way to engage with dualism is to engage with Descartes' arguments directly.

All the best,

Geoffrey