To: Kathleen C.
From: Geoffrey Klempner
Subject: Can solipsism be refuted?
Date: 12 May 2005 10:31

Dear Kay,

Thank you for your email of 4 May, with your fifth essay for the Possible World Machine, in response to the question, 'Can Solipsism be Refuted?'

This is a very good essay - I think the best you've done for me.

Using Descartes, Locke and Berkeley is a good strategy for getting 'in' to solipsism. As you acknowledge, none of these philosophers were solipsists but the idea of starting with sense experience tempts us in the direction of solipsism.

When Descartes conceives of the possibility of an evil demon, he is raising the spectre of an alternative source of his experiences from the one he previously believed in. Instead of coming from a world of material objects, my experiences come direct from the evil demon. In other words, solipsism never enters the frame. Despite all his doubting, Descartes never considers the solipsist alternative that experiences don't 'come from' anywhere but just are.

What the empiricism of Berkeley and Locke shows, however, is that just as human knowledge in general is limited to what human beings can learn from experience, so each of us is limited in a more profound way in that we occupy a perspective which is different from that occupied by anyone else. This is not solipsism as a metaphysical theory, but it does indicate an important sense in which each of us is ultimately 'alone'. I think this is what you want to say is the 'truth' in solipsism.

You give a very clear account of the argument that the solipsist is deprived of a concept of truth. There is only, 'I used to think p. Now I think not-p.'

This relates directly to Wittgenstein's private language argument. However, we need to make a distinction between the private language argument, and a move that Kant made against what he termed 'idealism'. Kant argues, in the 'Refutation of Idealism' (Critique of Pure Reason, 2nd edition - you will be looking at this!) that there can be no 'subject' who recognizes repeating elements of experience unless that experience is interpreted as perception of an external world of objects located in space. The point, however, is that this does not refute solipsism. The solipsist can just help himself to Kant's 'transcendental argument' for what he terms 'empirical realism'. My experience is necessarily an experience of an external world. That is as far as one gets.

It used to be (I don't know if it still is) a popular BA exam question to ask about the difference between Kant's refutation of idealism and the private language argument. Both Kant and Wittgenstein reject the idea of 'private objects'. However, I would argue that Wittgenstein goes further in insisting that the very possibility of making judgements presupposes that I am a subject amongst other subjects, who are in a position to correct me when I go wrong.

The tricky thing here is that it looks as though the solipsist can help himself to this too. 'Things must seem to me as if I am a subject amongst other subjects.' So the task becomes explaining why this is not enough.

Similarly, the argument you give that without the concept of 'others' there is no concept of 'myself' (see P.F. Strawson 'Individuals' Ch 3) seems to be one that the solipsist can happily take on board.

(Incidentally, Strawson's 'Individuals: An Essay in Descriptive Metaphysics' to give it its full title would be a good book to read along with the Metaphysics program. It was a seminal work (published in 1959) which did more than any other book to wrench Oxford philosophy out of its 'linguistic' mode, even though it is primarily the work of an 'analytic philosopher'. To this day, much of the vocabulary of metaphysics in the analytic style traces back to Strawson.)

Returning to the question of the truth in solipsism, I think that there is a 'truth in solipsism' which is not accounted for by the fact that each of us has our own limited perspective. It is not about knowledge at all, but about Being.

Here is my intuition: The world might have existed exactly as it does now, with GK writing an email to KC, without THIS. In other words, 'I' didn't have to be here at all. I am GK, but I might not have been. - Strangely, when I talk to students some agree on this intuition (intuitions are just raw material for the philosopher, not theories!) while others just don't see. I have never been able to give a satisfactory explanation for this.

All the best,

Geoffrey