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Refutation of solipsism, and the nature of concepts


To: Gordon F.
From: Geoffrey Klempner
Subject: Refutation of solipsism, and the nature of concepts
Date: Date 13 January 2006 17:21

Dear Gordon,

Thank you for your email of 7 January, with your answer to the question, 'Can the solipsist be refuted?' from the second selection of essay questions for the Philosophy of Language program, and your answer to the question, ''Concepts are not in a Platonic heaven, nor are they in the head. They are out in the world.' Discuss.'

Can solipsism be refuted?

I cottoned on pretty quickly that your 'solipsist' was in fact God, or, rather, someone who believes he is God.

This isn't solipsism, though it is an interesting question why. This is a point on which I have been guilty of a certain degree of carelessness, as you can see from this extract from unit 5 of the Metaphysics program:
161. Let us say, then, that the world is not my world. There is essentially more to the world than is to be met with in my experience, or could ever be, however indefinitely that experience were to be prolonged. That is a significant claim. Consider the following possible experience. Around my eightieth birthday I notice that my intellectual and physical powers, far from being in decline, are increasing rapidly day by day. By the age of one hundred and twenty it is clear to me that I am no ordinary human being, that I am indeed on the way to acquiring superhuman powers. By two hundred, I am ready for Mount Olympus. The universe looks a great deal smaller to me than it did when I was a mere human being. And now arises the undreamed of prospect of exploring every nook and cranny of my rapidly expanding or, rather, shrinking world in its entirety, as one might explore the objects in a room. Just a few years later I am, and know myself to be the super-mind that the mathematician Laplace hypothesised: having discovered the ultimate, deterministic physical theory, I know everything there is to know about the world, past, present and future. There are no more surprises. I am simply omniscient.

162. What we have just described is, arguably, a possible experience. Here is another. I am walking down a long white corridor, when I notice a door with a sign on it which reads, To be opened by authorised staff only. Overcome by curiosity, I open the latch. Inside is a frail old man in a dressing gown, sitting at a writing desk with his back to me. He turns round and stares at me for a few moments. 'I knew you'd come,' he says. 'Who are you?' I enquire. 'I am God. Pleased to meet you.'


I guess there are two questions: how you would prove to someone that he was not God, and what is the difference between believing you are God and being a solipsist.

As your dialogue shows, S is fully prepared to accept that even though you are a 'proper part' of S in one sense, you still have your own point of view. Whereas, the solipsist would hold that 'GF' is merely a name for a certain recurrent feature in the world of his possible experience.

How would you prove to someone that they are not God? Ask them a really difficult question and see if they know the answer? Obviously, that's not a logical proof in the sense which you discuss in the footnote to your dialogue.

Would my argument 'refuting' solipsism work against the God hypothesis? The argument against solipsism relies on the premiss that I occupy the only point of view, whereas the God hypothesis allows that there are other points of view. On the other hand, if you are God, then other persons do not have the 'authority' to correct your judgments, and this is the crucial point on which the argument against solipsism turns. In that case, it would seem that allowing the existence of other points of view isn't sufficient to defend the God hypothesis against the anti-solipsist argument.

'I know I am real, so you must be wrong!' when said to a solipsist is the equivalent of Dr Johnson kicking the stone in an attempt to refute Berkeleian idealism.


'Concepts are not in a Platonic heaven, nor are they in the head. They are out in the world.' Discuss.'

The point of the question was to consider the claim that there is a 'third alternative' in between Platonism and psychologism, which can be derived from Wittgenstein's rule-following considerations and the notion of 'forms of life'.

According to Wittgenstein, following a rule is a 'practice'. As a matter of ultimate, brute fact we go on in this way rather than that way. Although reasons for or against classifying a given entity as a 'cat' can be given and discussed, eventually reasons come to an end and we just do what we do.

Wittgenstein arrives at this view by considering the hypothesised role of the Platonist's 'forms' or psychologism's 'mental representations'. The form, or the mental representation, is meant to cover every possible case of cat or non-cat. It is a schema which we have in our possession, as a piece of knowledge 'in our heads', which we apply to experiences that we encounter.

The problem - and this is Wittgenstein's 'master argument' - is that whenever a schema is applied in a certain way, there is always the possibility that it could have been applied in a different way. The picture or the diagram or whatever it is that is in our heads does not, cannot, embody sufficient information to narrow down the range of possible interpretations to just one. Whatever the information, there is always the possibility of different 'interpretations'.

Hence, 'What this shows is that there is a way of grasping a rule which is not an interpretation, but which is exhibited in what we call 'obeying the rule' and 'going against it' in actual cases' (Philosophical Investigations 201).

This is the start of an answer to the question, 'What are concepts?' But it is not a question which Wittgenstein pursues. I would want to say that the concept of cat, for example, is 'out there in the world' because the classification has a 'point'. It is not just a set of characteristics which either match or do not match any given object in the world. The world has created us, and the other things we encounter in the world. Our sense of what belongs together or does not belong together is ultimately a brute fact, but it is not thereby 'arbitrary'. We are not 'free' to make up any concepts we like. This is one aspect of the givenness of 'forms of life'.

Your response to the question is to posit that concepts exist as 'brain states' which are common to different individuals. The language game with the word 'cat' is made possible by the fact that our brain states are sufficiently attuned with one another, and this physiological fact is, in a sense, 'in the world'.

This seems to skirt dangerously close to psychologism, but I can see how this could be made consistent with the 'forms of life' theory. Wittgenstein himself was very hostile to any attempt to talk of 'inner processes' like brain states, which he regarded as completely irrelevant to his purely logical inquiry into truth and meaning. However, as a matter of known fact, it is our brain states which give us the capacity to recognize cats and other things. It is OK to make this observation, provided that one does not fall into the trap of thinking that one has thereby found a way to 'bring the regress of interpretations to an end'.

All the best,