Tuesday, February 11, 2014

Solving Goodman's new riddle of induction

To: Stuart B.
From: Geoffrey Klempner
Subject: Solving Goodman's new riddle of induction
Date: 14th October 2011 15:35

Dear Stuart,

Thank you for your email of 10 October, with your University of London BA essay for the Methodology module in response to the question, 'What is Goodman's New Riddle of Induction? How if at all, can it be solved?'

I have no criticisms of this as a response to the question. You stick to the point, express yourself concisely, and offer what seems like a valid response. I take it that you are saying there never was a 'new riddle' of induction. It was just a dressed-up version of the old. I agree, but the question remains why Goodman goes to all this effort, and whether or not the effort is wasted.

I agree with you that the example of 'emeralds are green' is badly chosen. However, I think that the problem with this goes deeper than merely the problem that emeralds are green by definition. The problem is (as I think you also indicate) with the choice of a colour predicate.

Let's consider instead something totally off the wall, but which fully satisfies the logical elements of Goodman's riddle.

Call a 'experon' an academic philosopher examined before t, who is an expert about philosophy, logic and reasoning, or an academic philosopher examined after t who is a complete moron, unable to perform the simplest logical inference and ignorant of the problems of philosophy.

It would not be beyond the powers of a suitably endowed evil demon, to so arrange the world that, as a speaker of English would (from the point of view of a speaker of Experonish) 'perversely' describe it, academic philosophers change from being 'experts' before t to being 'morons' after t. While from the Experonish speaker's point of view, all academic philosophers naturally are, and remain, 'experons'.

Non-academic philosophers who are sufficiently knowledgeable to tell the difference between an expert and a moron would generally agree that academic philosophers are experts. However, it would not be beyond the powers of a suitably endowed evil demon to give non-academic philosophers the ability to tell the difference between an 'experon' and a 'morpert', an ability which they would deploy without even being aware of any change occurring at t.

Part of your point is that if you change one thing, lots of other things have to change too. But that's assumed in the example. You tell that someone is an expert by asking them questions. The brains of experts are different from the brains of morons. There's masses of data and theory that go towards accounting for the effects of study and education on human intellectual abilities. And so on. Add whatever you like to the mix. The bottom line, for Goodman, is that there is no way to prove by means of reason and logic alone that the predicates which we project are 'normal' rather than 'perverse'.

I think the answer to this is, why on earth would you want to 'prove it by means of reason and logic alone'? Goodman would consider that his point has been taken. It is rational to reason by induction, it is rational to prefer the predicate 'expert' to the predicate 'experon', because what we do, our practice, defines the standards of rationality. Every attempt to justify that practice, or find some deeper ground on which it supposedly rests, ultimately leads to circularity.

I would ultimately agree that the 'new riddle of induction' is just a dressed-up version of the 'old riddle of induction'. But the hocus pocus succeeds in making a point. Hume, and many philosophers since Hume, have focused their inquiry too narrowly, though I believe Hume would have been perfectly capable of seeing this had the question been put to him.

All the best,

Geoffrey