Tuesday, January 3, 2012

Defining truth by a majority vote

To: Kate S.
From: Geoffrey Klempner
Subject: Defining truth by a majority vote
Date: 29 September 2006 09:51

Dear Kate,

Thank you for your first essay for the Metaphysics program, which I received on 23 September, in response to the question, ''A statement is true if, and only if, the majority of persons of sound judgement would assent to its truth.' - How might one criticise this definition of truth using the reality principle?'

It was a pleasure to read this essay. On the basis of this piece of work I would have no hesitation recommending you for entry into a BA Honours course.

Your definition (b) is very similar in form to the account which Hume gives of taste. Hume takes a subjectivist view, aesthetic values are not out there 'in the world' but merely reflect human preferences. However, when applied to works of art, this would have the unwelcome consequence that there are no artistic works which through their intrinsic quality are worthy of appreciation, only what individual people 'like' or 'dislike'. Hume's solution is to define a class of persons of 'good taste' or 'refined sensibility' whose judgements have greater weight in determining whether a work has genuine aesthetic value or not.

There are various things you could say about how one determines whether an individual belongs to this restricted class or not, in terms of his or her knowledge and understanding, without presupposing in a circular way the notion of aesthetic quality. Hume goes to a lot of trouble in doing this. Obviously, it would be no use to define a person of refined sensibility as one who holds that a work has aesthetic quality only when it does indeed have aesthetic quality.

However, when we come to the analogous definition which you offer for truth, there does not appear to be any way to define what it is to be 'knowledgeable or wise' without reference to the concept of truth. It is part of the meaning of 'knowledge' that if X knows that P then P is true. Unless we can help ourselves to the concept of truth, it is hard to see how one can define a useful notion of 'knowledge' or 'wisdom'.

But is this a problem? Is there in fact a circularity here?

Maybe there could be a way to define what it is to be knowledgeable or wise, or have good judgement, in relation to a restricted class of truths, then use this notion to produce a general definition of 'truth'.

Suppose we could do this. Does such a definition necessarily have the consequence that a statement like, 'The earth goes round the sun' will be true at time t1 but false at time t2? In any case what could it possibly mean to say that a statement is true at one time and false at another?

'It is raining' is false today but was true at 10 am yesterday. However, the change of truth value is accounted for by an 'indexical' element. In fact, we are dealing with two different propositions, one of which is false and one which is true. 'The earth goes round the sun' (as normally understood) does not contain an indexical element. Either Galileo was right or he was wrong (discounting issues arising from General Relativity).

There is no coherent way to state such a 'relativised' notion of truth. This is because of the minimum requirement which any definition of truth must meet (on pain of simply not being a definition of TRUTH) that it licenses equivalences of the form, 'The earth goes round the sun' is true if and only if the earth goes round the sun.

'True' is the only predicate which you can apply to any quoted statement which is equivalent to removing the quotes (the 'predicate of disquotation'). Some philosophers have argued that this is all there is to the definition of truth (so-called 'redundancy' theories or 'minimalist' theories). The problem with the minimalist view is that it leaves us with a question that we still want to answer: 'What is it that all true statements have, which false statements lack?' We feel we ought to be able to say something informative about this.

But maybe not.

Applying the reality principle, you are led to the conclusion that truth is independent of human judgement. We can never be sure, when we make a judgement, that our judgement is true. Truth may be 'out there' we can never be sure of reaching it. This is the view of the realist about truth (who we will meet later in the program).

So we are brought back to the notion that truth does, after all, have something to do with agreement in judgments. After all, we use the notion of truth. The notion would not have any use if we could not say when a statement is true or not.

I will refrain from saying any more, because we are already getting deeply into the issues discussed in the program. As you will see, I argue that you don't have to be a realist about truth in order to accept the reality principle. The question is how far off realism one can go without falling foul of that principle.

All the best,

Geoffrey