Giorgio Sbardolini (University of Ohio)
May 30 MON — 10.30-12.30
Sala "Enzo Paci" — Direzione del Dipartimento (Via Festa del Perdono 7, Milano)
Two-Dimensional Russell Paradox
Abstract: I will present (what appears to be) a version of Russell's paradox in two-dimensional modal logic. That is, there is a reductio argument that is structurally identical to Russell's paradox, following from apparently natural assumptions that can be formulated in a two-dimensional modal logic of the type underlying Kaplan's logic of indexicals, or Stalnaker's metasemantic account of assertion. As usual, the question is: what is this a reductio of? In order to approach this question, I will discuss Prior's paradox: an apparently closely related contradiction that belongs to an underinvestigated class of puzzles, known as "paradoxes of intensionality."