Interworld Disagreement

Disagreement plays an important role in several philosophical debates, with intuitions about ordinary or exotic cases of agreement and disagreement being invoked to support or undermine competing semantic, epistemological and metaphysical views. In this paper we discuss cases of (alleged) interworld doxastic disagreement, that is to say, cases of doxastic disagreement supposedly obtaining between (the beliefs of) individuals inhabiting different possible worlds, in particular between an individual inhabiting the actual world and his/her counterpart in another possible world. We draw a distinction between propositional and attitudinal disagreement, bring it to bear on the issue of the conditions of this kind of disagreement, and raise some metaphysical and epistemological worries about the claim that an individual inhabiting the actual world can disagree with an attitude or a speech act of his/her own counterpart, or of another individual, in a different possible world.