Abstract

Are facts about numerical identity contingent? Is it ever the case that a is b, but might not have been? Or that a and b are two, but might have been one? Our two leading approaches to modal semantics – Kripkean Quantified Modal Logic and Lewisian Counterpart Theory – give opposing answers. QML says the identity facts are necessary; counterpart theory that they are radically contingent: I could have been you, and each of us could have been a poached egg. I don’t think I could have been a poached egg. Being a person is essential to being me. Same for you. But do our respective essences keep us essentially apart? Or do they allow for contingency in our distinctness? I offer a theory of real contingent identity. De re modality is not merely a matter of resemblance, as it is for Lewis, but rather a deep metaphysical notion, grounded in our essences.