To: Kathleen C.
From: Geoffrey Klempner
Subject: Mind-body problem and the refutation of solipsism
Date: 21st July 2008 12:04

Dear Kay,

Thank you for your email of 6 July, with your fifth and final essay for Pathway Philosophy of Mind, in response to the question, ''The world is my world.' Explain how the theory of solipsism arises in the context of the mind-body problem. Can the solipsist be refuted?'

Congratulations on finally completing the Pathways Philosophy of Mind program. I will be forwarding your Pathways Certificate together with my summary report to the Secretary of the ISFP, who will then send these on to you.

This is not such a 'miserable effort', as you described, and the topic should tie you in knots. The whole question of solipsism is incredibly difficult, and I would certainly not claim to have given the definitive account of it.

First things first. Solipsism arises in the context of the mind-body problem, as you indicated, when we raise doubts about the existence of an external, material reality and seek to answer them on the basis of the fact that something is given to us, sense data or immediate experience. This was a question that Descartes raised, but he never went the way of solipsism. Why? If you look at Meditation 1 you will see that never once, despite all his doubting, does Descartes even consider that 'my experience is all there is'. When he tries to manufacture the most extreme sceptical hypothesis that he can, he comes up with the idea of an 'evil demon', an 'other', who is the provider of my experience and who has (consequently) their own perspective on the 'world of Descartes' although Descartes doesn't pursue this point.

The solipsist sweeps all this away. There is nothing to reason *from* the data, there is no speculating on what ultimately *produces* the data. There is only the data. That's all I have, all I will ever know.

Now comes the finesse. Wittgenstein's private language argument shows that I cannot describe my data, just as it is, because 'whatever seems right to me will be right'. However, Kant provides the solution: according to Kant's 'Refutation of Idealism' (from the 2nd Edition of the Critique of Pure Reason') in order to have knowledge of my own experience, it is necessary to apply spatio-temporal concepts to it. It is necessary, in other words, to identify 'objects' (including, as you note, other people) which have properties, are located at places, are conceived to 'exist' when I am not perceiving them etc. etc. (Remember unit 4 of the Metaphysics program!)

We still only have the data. But what Kant's argument shows is that I can only *talk* about an external world, and the properties of objects which occupy places in the world (including myself and my physical and mental state).

BUT: this is still solipsism. The term sometimes used is 'transcendental solipsism'. Kant was not a transcendental solipsist, because in addition to the world of phenomena, he posits a realm of noumenal 'subjects' and 'objects', the ultimate source of each stream of experience (although like talk of the noumenal world itself, this is something about which nothing can be said).

Kant doesn't give a very convincing reason for believing in noumena, in fact it is difficult to find any argument. However, we wouldn't really want a refutation of solipsism which required the apparatus of phenomena and noumena.

So, after all this, how is the solipsist to be refuted?

As you show, Wittgenstein still has something more to say here, along the lines of the 'impossibility of being wrong'. Only we have to step up a level. The transcendental solipsist has the means for distinguishing between 'appearance' and 'reality', is able to say things like, 'I seem to see a pink elephant but I know that there is no pink elephant there.' The transcendental solipsist makes judgements, and tests these judgements against experience, sometimes discovering that her judgements were wrong and need to be revised. Why isn't that enough?

It is not enough, because the transcendental solipsist is still the 'final authority'. There is no room in this model for another perspective. She allow other 'persons' to correct her judgements, acknowledging when someone is an expert on a topic or a useful source of knowledge. But this is just more along the lines of 'reasoning from experience'. In the same manner, I can allow a thermometer to correct my judgement that 'it is hotter today'. For the solipsist, other persons are just my measuring instruments.

So it would not be correct, as you imply, to equate the rejection of solipsism with the recognition that other people can correct my judgements. The solipsist is happy to admit this. What the solipsist cannot admit is the actual *existence* of other viewpoints, the possibility that I am wrong which cannot be reduced, in the manner explained above, to the possibility of finding out that I am wrong.

In your penultimate paragraph, you describe a 'less extreme view', according to which 'there was a world outside her that was the source of her mental images. She would never be able to know if this world corresponded in any way with the world in her mind, but its regularity, lack of chaos and recognisable patterns would allow her to accept that the images in her mind do not arise as dream thoughts or phantoms.' - I think this is the point where perhaps you did get confused. The description looks very much like what I said above about Kant's Refutation of Idealism. There is a necessary order and regularity in my experience which permits its interpretation *as* a world of external objects. However, necessarily, these objects are knowable. I can discover whether my judgements correspond with facts about this world.

However, you have raised a valid question about whether there is room for a position in between solipsism and recognition of the reality of other points of view, which would allow that *something* exists apart from the world which I construct on the basis of the given data, even though this something does not support the reality of other subjects. There is just me, and an external world of matter.

This position seems to correspond with the traditional 'problem of other minds', according to which I know there is something (consciousness) in me but do not know whether there is consciousness in anyone else. In effect, it is the 'zombie hypothesis' used to stimulate anti-materialist (pro-dualist) intuitions. (Look up 'zombies' and 'David Chalmers' in Google.) It is sufficient for refuting this version of solipsism to refute mind-body dualism. But that's a different essay topic!

All the best,

Geoffrey