Short Abstract

Colocationism claims that two non-identical objects can be composed of the same parts. One of the most challenging questions for colocationism is the grounding problem: what grounds the difference in, for example, sortal properties of two colocated objects? Catherine Sutton has recently offered a new ingenious answer to it. She distinguishes between extrinsically and intrinsically composed objects and claims that two colocated objects share their parts, but at most one of them is intrinsically composed. Moreover, when the two objects are extrinsically composed, the relations that their parts stand in to other things are different. This is Sutton's answer to the grounding problem: the different relations that the shared parts of two colocated objects enter into ground the objects' different sortal properties.

In this paper I argue, against what Sutton claims, that pieces of matter are intrinsically composed. This implies that there are intrinsically composed colocated objects. However, Sutton has no answer to the grounding problem for this kind of case. Moreover, I formulate my own account, which although it has some features in common with Sutton's, it takes appropriately into account cases in which the two colocated objects are both intrinsically composed. I introduce the concepts of a process of coming-into-existence and of the minimal-internal-structural-configuration of an intrinsically composed object and then I elaborate my answer to the grounding problem: the fact that two objects have different sortal properties is grounded in the fact that the processes of coming-into-existence of the two objects are different in a significant way.