Saturday, December 22, 2012

Descartes on perceiving beeswax and the case for doubt

To: Stuart B.
From: Geoffrey Klempner
Subject: Descartes on perceiving beeswax and the case for doubt
Date: 21st January 2009 11:54

Dear Stuart,

Thank you for your email of 11 January with your essay in response to the University of London Modern Philosophy question, ''I must... admit that the nature of this piece of wax is in now way revealed by my imagination, but is perceived by the mind alone' (Descartes Second Meditation). What led Descartes to this view? What is its significance?', and your email of 16 January, with your essay in response to the Modern Philosophy question, ''There is not one of my former beliefs about which a doubt may not properly be raised' (Descartes). Does Descartes succeed in showing this in the First Meditation?'

The beeswax passage

This is a difficult topic. You take a clear line that Descartes' conclusions regarding the beeswax essentially involve his philosophy of mind-body dualism. Your reasoning is plausible. But is that the only way to read this passage?

As you remark, Descartes uses 'perceptions' in two senses, the perception made by the mind and the 'perceptions' of the senses. Let's use a terminology which Descartes could hardly have objected to, calling the perceptions of the senses, 'sensations'. We can leave it an open question whether it would be correct to label Descartes as a 'sense datum theorist'. The distinction between sensation and perception does not require belief in 'sense data' as such (See D.W. Hamlyn 'Sensation and Perception' RKP).

One thing we need to do is determine what it is that Descartes puts forward as the alternative to 'perceiving with the mind'. If that is the answer, what was the question? what is the alternative?

Here is one widely accepted view (which you will find e.g. in David Wiggins 'Sameness and Substance' Blackwell). 'Wax' is a sortal concept. Identity over time is spatio-temporal continuity under a covering sortal concept. Part of grasping the concept 'wax' is understanding the various possible changes that a piece of wax can undergo, and not be destroyed.

Of course, there is a huge question here about the underlying explanation for changes of this sort: in effect, the clash between the Aristotelian hylomorphic view and the atomism of Democritus. Descartes is reasoning like a good Aristotelian. It is the mind that comprehends the 'form' of wax, that which determines the changes that wax can undergo while remaining wax.

In these terms, the 'alternative' would be some kind of phenomenalist theory which defined the piece of wax in terms of sequences of sensations or possible sensations. Descartes' point would seem to be that such a definition cannot be given. Consulting my concept of wax -- or my more general concept of organic substance -- any change which is not irreversible is allowed. Empirical investigation later tells us what some of these changes are (e.g. we discover that wax can be vaporised and condensed, provided care is taken to prevent it catching fire).

If this interpretation is correct, then Descartes is wrong in thinking that his experiment with the beeswax supplies support for mind-body dualism as such. What it does do, is illustrate Descartes' concept of substance, and indirectly legitimise the view that the mind or the body can both be a 'substance', that is say, an entity with an identity whose conditions are determined by a covering sortal concept.

Descartes' argument for doubt

This is a bit of a mess. First, I don't think that it is a valid approach to introduce Descartes' theory of mind-body dualism into his reasoning concerning the 'things that may be doubted'. The whole point of this exercise is that the reader is expected to assent, prior to knowing anything about Descartes' theory. The success or failure of Descartes' argument in the first meditation depends on this.

Your introduction of the beeswax example looks clearly wrong here. As I remarked above, we can learn from our sense perceptions that, e.g. it is possible for wax to vaporise and condense.

There is no objection in principle to mentioning Descartes' arguments over the indubitability of 'I' and then his argument for God. However, the quote relates to 'my former beliefs' which implies that we are addressing a reader who has not yet considered these things.

The meat of the question is therefore in Descartes' use of the argument from illusion, dreaming and the evil demon hypothesis. Descartes himself makes clear that the argument over misperception is merely intended to sharpen the question -- we learn by sense experience that our sense perceptions are sometimes mistaken. However, it also enables him to distinguish between the given in perception and the external object perceived, a distinction which he needs in order to proceed to the next stage of the argument.

The argument from dreaming and the evil demon raise substantial philosophical issues (with which you are very familiar). You are expected to air this knowledge in your answer, demonstrating to the examiner that (possibly) you can see a way in which Descartes has overstated his case, or, alternatively, agreeing with Descartes' conclusions.

All the best,

Geoffrey