Supersubstantival composition as identity

Abstract

The most popular form of supersubstantivalism claims that each material object is identical to its location. Composition as Identity (CAI) claims that each material object is identical to its parts taken together. These two theories are crying out for unification: they share many commitments, they can solve problems for each other, and the theory that results from their combination is elegant and powerful. Elegant because it unifies three phenomena (composition, location, and identity) and two different theories (supersubstantivalism and CAI). Powerful because it puts one relation (identity) to a great deal of work, using it to offer answers to the general and special composition questions as well as solutions to various mysteries about the relationship between material objects and spacetime. The work of this thesis is to combine supersubstantivalism and CAI into a new theory. I call this new theory supersubstantival composition as identity. Or, super-CAI, for short.

In the course of advocating for super-CAI, I offer some new advances for related literature. I show how to make a restricted view of composition consistent with CAI and with supersubstantivalism. I show that supersubstantivalism is consistent with failures of harmony. I develop a method of relativising is one of predications to ways of counting. And I explain why colocation of physically discernible material objects is (at least physically) impossible. All while offering a systematic defence of a novel theory of composition and location.