Scott Soames' "Actually" in Vegas
One of my favorite philosophers, Scott Soames, was in Vegas last weekend; he gave a great talk entitled "Actually", and he and his wife Martha took a trip with some of the folks in my department out to the beautiful Valley of Fire state park.
One of the main points Soames pushed was that "actually" plays two very different roles in philosophical semantics. 'Actually p', spoken in a given world W1, means 'p is true in world W1' (sorry, I can't do corner-quotes in Blogger). Now, Soames says there are two ways to specify this world W1:
(1) by picking it out purely indexically, in the way 'I' picks out the speaker of the token, 'now' picks out the moment of utterance, etc. -- so on this way, 'actually p' means 'p is true in THIS world' (or '...in OUR world').
(2) by (roughly- see Soames' paper for the gory details) giving the proposition associated with the Carnapian state-description of W1. (A state-description assigns a value of true or false to every atomic sentence in a language.)
Scott pointed out that if we pick out world W1 in the second way, then 'Actually p' is a priori: once you have a state-description of the world in which that sentence is uttered, then you have all the information you need to figure out its truth-value. This runs contra the conventional wisdom that says 'Actually p' is a posteriori, since we only learn whether p is true in this world via experience; Soames's point was that 'Actually p' is learned via experience when we use way (1) of picking out the world W1, but since there is this other way (2), 'Actually p' is in fact knowABLE a priori, if not knowN a priori in practical cases.
This is very clever, and I need to think more about it, but I think my esteemed colleague James Woodbridge had the best question/ objection of the afternoon. He said 'Actually p' does not just mean 'p is true at world W1,' but rather 'p is true at W1 AND W1 is actual/ instantiated.' Someone could give me the entire state-description of the world we currently inhabit, and then I could calculate from that description that p is true in a world satisfying such a description -- but I still wouldn't know that 'Actually p' is true, because I wouldn't know that the state-description matched this world. (And I was too slow on the uptake to grasp Soames's reply to James.)
My favorite part of Soames's whole talk, though, was the following approximate quotation:
"Perhaps the contingent a priori is just an old wives' tale."
I know I can't get my grandmother to stop talking about Kripke...