Saturday, August 23, 2008

Parsons's Mathematical Thought: Secs 24-26, Intuition

Chapter 5 of Parsons's book is called "Intuition". And I guess I should declare an interest (or rather, lack of interest!) here. I've never really understood talk about intuition: and I'm certainly not helped when Parsons writes "I shall be concerned to develop a conception of mathematical intuition that is in a general way Kantian", since Kant is pretty much a closed book to me. So perhaps I'm not the best reader for this chapter! But still, let's proceed ...

Sec. 24, "Intuition: Basic distinctions". Parsons distinguishes supposed intuition of objects from intuition that such-and-such is the case. And he stresses that in his usage, intuition that isn't factive. So is an intuition that such-and-such just a non-inferential belief? Well note, for example, that "knowledge without observation" of our own bodily movements is non-inferential, but is not normally counted as intuitive. So what differentiates intuition properly so-called? Parsons promises an answer by a "development of the concept ... in the Kantian tradition".

Sec. 25, "Intuition and perception". Now, the headline suggestion here is that "It is hard to see what could make a cognitive relation to objects [intuition of] count as intuition if not some analogy with perception" (cf. e.g. Gödel). Further, intuition that is intimately connected with intuition of, rather as perception that is grounded in perception of. Well, fair enough: but that, of course, already does make claims about intuitions of mathematical objects very puzzling. Which leads to ...

Sec. 26, "Objections to the very idea of mathematical intuition". Start with the following point. Ordinary perception is (so to speak) evident to the subject -- when I see an object, my computer screen say, "there is a phenomenological datum here". But "it is hard to maintain that the case is the same for mathematical objects ... [Are] there any experiences we can appeal to in the mathematical cases that are anywhere near as indisputed as my present experience of seeing the computer screen?" This seems to undermine any alleged analogy between "intuition of mathematical entities" and ordinary perception. So how are we to defend the analogy, given the different phenomenologies? Unfortunately, Parsons next remarks here are Kantian obscurities I can do nothing with. So I'm left stumped.

(Parsons also raises a question about the relation between structuralist thoughts and claims about intuition. The worry seems to be one about how a particular intuition can latch on to a particular object, if mathematical objects are indentified by their places in structures. The point, however, is rather rushed. But since I think Parsons is going to return to these matters, I won't say more at the moment.)

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