Session chaired by : Louis Rouillé (Collège de France)
Abstract
Some ideas from aboutness theory are applied to the problem of logical "nescience" (= logical non-omniscience). Little insight is provided into this problem by the picture of propositions as sets of worlds. If propositions are made up, not of the worlds where S holds, but its ways σ of holding, then we begin to see why equivalence would be opaque. S and T are equivalent just if the same piece of logical pottery is obtainable either by (i) fitting the propositional shards σ in the S-pile properly together, or (ii) fitting the shards τ in the T-pile properly together. This suggests an analogy with Frege's puzzle about informative identities-which might or might not be found encouraging.
Stephen Yablo
Stephen Yablo has been at MIT since 1998, having taught previously at the University of Michigan, Ann Arbor. He specializes in metaphysics and philosophy of math and language. Author of Thoughts, Things, and Aboutness, he gave the Hempel Lectures at Princeton in 2008, the Locke Lectures at Oxford in 2012, and the Whitehead Lectures at Harvard in 2016.