I should start this post by pointing out that I haven’t read Stanley’s book, I didn’t have anything to take notes at the session, and all I know about subject-centered invariantism (which I believe is Stanley’s position on knowledge) is what I learned in John MacFarlane’s seminar last year, and occasional discussions with other people. But even given all that, it was quite an interesting session – and other people seem to agree on that, given that it seemed to have the largest audience. (I was sitting on the floor most of the time, with about a dozen other people – there were two other sessions with similar-sized audiences in even smaller rooms, so they were even more crowded.)
Stanley’s position is “invariantism” in that he denies that the situation of the asserter plays any important role in the proposition expressed by “A knows that p” or its truth value (unlike, say, Keith DeRose and others, some of whom suggest that the salience of relevant alternatives in the context of utterance can make “Jane knows that she has hands” go from true (in most contexts) to false (if one has just considered that she has no way to rule out being a brain in a vat)). However, it is “subject-centered”, because having made exactly the same observations, A can know that p while B doesn’t, if something of extreme urgency for B (but not for A) depends on whether p. (Stanley pointed out that there is a connection between “evidence” and “knowledge”, so we have to talk about something more like observations than evidence.)
I don’t remember too many details of the session (though I know I’d like to get a copy of Stephen Schiffer’s handout, since he made a bunch of very interesting points, and seemed to have handed out something like a full transcript of his remarks), but there was one interesting objection raised in the question period by Ryan Wasserman. Jason Stanley had already bitten the bullet and agreed that if John and Jane are on the same airplane, and have the same information about windspeeds and departure time and the like, but Jane has an important talk to give very soon after arrival, then John can know that the plane will arrive on time even though Jane doesn’t. This seems somewhat odd, and Ryan Wasserman pushed it further by pointing out that on Stanley’s position, this can even be possible if Jane has gathered more information about the weather, history of the airline’s performance, and the like.
After Jason Stanley’s response, Delia Graff (who was chairing the session) tried to defuse the worry that the theory makes such predictions by pointing out a related prediction of a related theory. It seems perfectly fine for her to say that her 9-year-old cousin is really really good at playing basketball, and that Ryan Wasserman plays basketball even better than her cousin, but that Ryan Wasserman is not very good at basketball (despite being better than someone that’s really really good at it). The fact that this prediction is perfectly fine for subject-centered invariantism about “good at basketball” (rather than “knows”) seems to support subject-centered invariantism.
At first I agreed with her, but now I think that this piece of evidence actually counts against Stanley’s theory. I think (correct me if I’m wrong) the intuitions suggest that the basketball case sounds much better than the knowledge case. If subject-centered invariantism about both predicates predicts that both should be acceptable, then this suggests that something like subject-centered invariantism may well be true for “good at basketball”, but probably isn’t true about “knows”. If it did apply to both, then in addition to explaining away the intuition in the case of “knows”, Stanley would have to explain why the intuition reappears for the basketball case. Now, it’s possible that such an explanation will emerge (as it will have to if one thinks that subject-centered invariantism is wrong for both predicates, as I think that I do), but it’s quite a convoluted way to get at the data from Stanley’s theory, and starts to disconnect the theory somewhat from the evidence.
Anyway, it’s interesting stuff.