Blog powered by Typepad

Enter your email address:

Delivered by FeedBurner

Your email address:


Powered by FeedBlitz

Become a Fan

« The survey results | Main | Remembering heroes »

December 12, 2009

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00d83452b54c69e20128764ae250970c

Listed below are links to weblogs that reference Modal Realism and Oracles:

Comments

Feed You can follow this conversation by subscribing to the comment feed for this post.

www.philosophyetc.net

One shouldn't take "oracle" talk too seriously. It's really just a shorthand to get us thinking about conditional probabilities/credences. E.g. Cr(Modal Realism | only one concrete world) is near-zero, whatever one's prior credence in Modal Realism. By contrast, Cr(Utilitarianism | murdering Bob increases happiness) = Cr(Utilitarianism).

Aaron Boyden

Hmmm. Not sure exactly why Cr(modal realism|only one concrete world) shouldn't be equal to Cr(modal realism). Modal realism with only one concrete world sounds like Quine's view, and I'm not sure that lowering one's credence in modal realism, rather than appropriately increasing one's credence in skepticism/nihilism about modality generally, is the rationally appropriate response for someone who puts significant credence in modal realism and who obtains evidence that there's only one concrete world.

I'm also a bit skeptical about trying to apply probabilities to a priori matters; I suppose there has to be some way to talk about appropriate credence in such matters, but it seems dangerous to assume that we can just talk about them in exactly the same way we talk about contingent matters.

www.philosophyetc.net

Lewis, at least, argued for modal realism on the basis of various theoretical payoffs (accounts of propositions, properties, etc.) that would be completely undercut by the loss of a plenitude of worlds.

Things might be different for someone who accepted modal realism on different grounds, e.g. skepticism about abstracta. They would then be subject to the epistemic objections Ross raises. If my account (of when it's legitimate for a theorist to reverse the metaphysical and epistemic orders of explanation) is correct, then it would *not* be legitimate for your kind of modal realist to offer the Lewisian inference, "talking donkeys are possible, therefore there's a concrete world containing a talking donkey".

The comments to this entry are closed.