Those who accept an ontology of ordinary objects face the problem of colocation: holding that different objects — such as a lump of clay and a statue — occupy the same place at the same time or are composed of the same parts. Anti-colocation arguments appear in several forms: rhetorical appeals that surely there is nothing “over and above” the clay, claims that this violates the plausible principle that no two objects may share the same space or parts, and worries that this falsely leads to “doubling up” property instances (such as weighing ten pounds). This chapter aims to defuse all these related worries. We are then left with the grounding problem: how can two objects share all the same parts and non-modal, non-sortal properties, yet differ in their identity and persistence conditions? It is argued that the modal conceptualist view of Chapter 3 provides the key to resolving this problem.
Keywords: grounding problem, identity conditions, persistence, sortal, modal property