Abstract

This chapter examines questions having to do with whether and how things persist through change and how things do so If they do persist. Next, assuming that intrinsic change does take place, the chapter examines two principal views about how things persist through change of intrinsic properties, Substratism and Replacementism. It focuses on the specific but very important case of motion, or change of location. There are three major theories: Intrinsic Motion; Bertrand Russell's At/At Theory, and an Aristotelian theory (Motion Intervalism). The chapter also considers the problem of the persistence of composite objects, including objects that can gain or lose parts. Replacementists might consider taking on board a metaphysically fundamental genidentity relation. Substratists have an explanation for the reflexivity, symmetry, and transitivity of genidentity, something that Classical Genidentity Theorists have to posit as a brute metaphysical necessity. This provides the Substatists with an advantage in terms of Ockham's Razor.