To: Simon Y.
From: Geoffrey Klempner
Subject: Argument for universal doubt in Descartes 1st Meditation
Date: 13 September 2007 12:51

Dear Simon,

Thank you for your email of 8 September, with your University of London essay in response to the question, 'In his First Meditation, how does Descartes attempt to show that there is reason to doubt everything one believes?'

This is a difficult kind of question to face in an exam, because on the face of it you are simply being asked to summarize a philosopher's argument. However, there is always more to it than that. And I am pleased that you found points on which Descartes can be criticized, or where there is unclarity in what exactly he is setting out to do.

For the purposes of this essay, we can distinguish two aims, a destructive aim and a constructive one. The destructive aim is to 'show there is reason to doubt everything one believes'. The constructive aim is to find some means to repel this doubt, or defend against it. However, the essay question is not asking for Descartes' constructive response.

It is part of the constructive endeavour to seek 'secure foundations for his beliefs'. The point that you make in the sentence that begins, 'He believes, therefore that all of his beliefs should be questioned...' can be better made by saying that in seeking to cast doubt on a set of beliefs it is necessary only to undermine the principles which serve as a necessary foundation for those beliefs.

Later, in Meditation 3, Descartes will find an alternative foundation, which does in his view resist all attempts at doubt. But we are not concerned with that here.

You make a good point when you say that logical relations between beliefs can be complex, so it is not always easy to identify a 'foundation' for the sceptic to attack. Indeed, this is a version of one of the arguments put forward by epistemologists who reject foundationalism altogether.

Your examples of astronomy and biology are relevant because they show how a limited area of knowledge can be put in question by doubting the principles upon which that area is based, while leaving the rest of one's beliefs intact.

Your most substantial point, however, concerns the way that Descartes deftly avoids the problem of how he knows he is not delusional. If you are interested, there is a book by Harry G. Frankfurt, 'Demons, Dreamers and Madmen: the defense of reason in Descartes Philosophy' http://press.princeton.edu/titles/8588.html which explores this particular issue. You are right to say that Descartes wouldn't even be conducting his Meditations if he was not at least able to assume that he is capable of reasoning.

Does this get Descartes off the hook? I don't think so. The reason is the one given, effectively, in Wittgenstein's argument against the possibility of a 'private language': the first-person standpoint cannot ultimately be self-sufficient. It is a meaningful question to raise whether I can trust my own reason. It's not enough to point out that a person can uncover lapses in rationality through the discovery in contradictions between one's beliefs, because there is always a way to patch up a seeming contradiction; as demonstrated in cases of paranoid delusions. It follows that the question is one that can only be answered by the observer of my behaviour. The attempt to erect a system of knowledge on the basis of the first-person is doomed to failure.

What you say about there being aspects to one's own mind which are not transparent to the first person is relevant to this. The very possibility of there being more to my own mind that is available to first-person introspection points to the fact that a 'mind' is something that belongs to a person in a world, whose behaviour can be observed, who is capable of being challenged to give an account of oneself and one's actions by others.

Admittedly, a Freudian would insist that the possibility of 'discovering' aspects of the unconscious depends upon 'making the unconscious conscious'. That is why so much stress is placed in analysis on the patient accepting the psychoanalyst's interpretation. But that is not enough to save Descartes' project. Ultimately, the patient and the analyst have to agree on the outcome that has been achieved.

If I was being picky, there are steps in Descartes' argument that you don't look at: his deployment of the argument from illusion, the reply that the senses can be used to correct errors made by the senses, which then moves on to the point about 'general ideas'. Otherwise, this is a good first essay.

All the best,

Geoffrey