To: Hakeem G.
From: Geoffrey Klempner
Subject: Descartes 'I am a thinking thing'
Date: 16 January 2007 11:53

Dear Hakeem,

Thank you for your email of 2 January, with your essay in response to the University of London question, 'Explain and evaluate the argument Descartes gives in the second meditation for the claim that he is a thinking thing.'

This is a good piece of work.

In answer to your question, it can sometimes be hard to distinguish between an exposition of the text and a critique. For example, if the meaning of the text is unclear, the process of exposition might well involve putting objections and replying to those objections, with the aim of identifying the most 'charitable' interpretation (according to the so-called 'principle of charity') which involves selecting the one interpretation from various plausible candidates which makes the strongest case.

Having given your philosopher the strongest case, you can then proceed to demolish it (or give reasons why you accept it). This would be the evaluative part of your essay.

Regarding plagiarism. Your worries about using arguments of other philosophers are unfounded. It is perfectly acceptable to say, 'Strawson objects that so-and-so', or 'Strawson argues that so-and-so'. If you are quoting someone who you have talked to or corresponded with (like me) you can just say, 'It has been put to me in conversation that...' without giving the name of the individual involved.

If you are using a direct quotation, you must use quotation marks. If you are quoting indirectly then you should not use quotation marks. For example, Strawson says, 'No entity without identity' (direct quote); or, according to Strawson we cannot talk about an entity or object unless we are able to provide identity conditions for that object (indirect quote).

Now to your essay.

You need to find a way to identify the essential steps in Descartes' argument, without going to the extreme of paraphrasing or giving a precis of what Descartes actually says, paragraph by paragraph. A good exercise is to try to express the content of the argument in numbered steps. What is the least number of words needed to convey the essence of Descartes' argument for the claim that 'I am a thinking thing'?

I would start the essay by identifying two claims in Descartes' statement: first, the claim that I think, and secondly the claim that I am a 'thing'.

What is thinking? You have said quite a lot about this. According to Descartes, acts of thinking can be separated into a purely mental component and a physical component. For example, sense perception as we normally understand it involves a relation to the physical world, but according to Descartes we can separate this into the 'thinking' component, the pure acts of conscious experience, and the physical component, which is their purported relation to the physical world. And so on.

What is a thing? Descartes has something to say about this: a thing is a 'substance'. A substance is something that persists over time, which has essential properties without which it would not exist, and accidental properties which are different at different times.

In your essay you consider to main lines of objection. The first is well known objection that all that he is entitled to claim, in the face of the hyperbolic doubt generated by the evil demon hypothesis is that I exist now. This is not sufficient to establish that I exist as a substance, because a substance persists through time.

I didn't understand the reply which you offered to this objection, in defence of Descartes. Even as a thinking thing, I do not have to believe everything my memory tells me. For example, at breakfast I remember being chased by a green dragon. Later, playing the dream over in my head, I decide that it wasn't a dragon but a tyrannosaurus rex. So I believe my original memory was false. However, in the face of the hypothesis that the evil demon has brought Descartes into existence one second ago, there is no reply.

Your second objection is interesting. This is that in describing his essential nature as a non-physical thinking 'thing', Descartes in fact relies on physical metaphors and concepts. It is impossible to use the language of a 'substance' without bringing in ideas from the physical world. Another way to put this is that we have no idea of what existing as a 'thinking substance' would be were it not for the fact that our experience is 'as of' a physical world.

My feeling is that Descartes can defend himself against this objection. He can accept that he has no idea of what it would be like to be a thinking substance in the absence of experience. In that case, it would follow that in order to bring about the existence of the thinking substance 'Descartes' it would be necessary for the evil demon to create an apparent 'world'. However, this is fully consistent with the claim that Descartes is in reality a 'thinking substance', which can exist even if this appearance is a mere illusion, albeit a necessary illusion.

All the best,

Geoffrey