I’ve been reading Scott Soames’s 20th Century history books, and I’ve been surprised by a few things. Here’s one little New Years Eve puzzle for you that arises out of some things in the book: did Kripke show that there are synthetic a priori propositions?
At various places Soames seems to take this to be important. It’s a mistake, he seems to say, to identify the analytic and the a priori. Not as big a mistake as identifying the necessary with either of these, but still a mistake. (At least he seems to say this is a mistake in the discussion of Wittgenstein – I’d be happy to have it shown I’ve misinterpreted him here.) But we never get a conclusive example of a synthetic a priori proposition.
I’ve “argued previously”:http://brian.weatherson.org/sre.pdf that propositions like _I’m not a brain in a vat_ are knowable a priori, though they are pretty clearly synthetic. And I’m disposed to think that mathematical truths are synthetic a priori, as are some metaphysical principles like _There is no metaphysical vagueness_ and _Any two objects have a fusion_. So I’m happy the analytic and the a priori are separate. But Soames doesn’t discuss these, and nor does Kripke, so they don’t show that _Kripke_ showed the two concepts are distinct. (I’m bracketing here discussion of whether Kripke _couldn’t_ have _shown_ the two are distinct because showing in this sense implies novelty, and Kant beat him to it.)
Soames does discuss examples like _The metre stick is a metre long_ and argues, convincingly in my view, that these are not contingent a priori. He also argues, again I think convincingly, that propositions like _Snow is white iff snow is actually white_ are *contingent* a priori. Is that enough?
Well, that depends on how we view the case. Two options arise. First, we might say that all contingent propositions are synthetic, and hence this is an example of the synthetic a priori. But there’s another option, which is to say _Snow is white iff snow is actually white_ is an example of the contingent analytic. Why should we believe that? Well, one reason is that the argument Soames gives for it being a priori knowable (and hence true) seems only to rest on premises about the meanings of terms involved, especially of the _actually_ operator. So it looks to be analytic. That would suggest there are no Kripkean examples of the synthetic a priori.
Now that I’ve written all this it strikes me that there must be literature on this question somewhere. But I’ll leave the lit search to the new year.
Happy and safe New Year everyone!