An Explanation of Complete Colocation of Indiscernibles

Abstract

The Principle of the Identity of Indiscernibles (PII) claims that objects that share all of the same properties are the same object. If this claim is denied, then, as is commonly believed, the denier must accept the possibility of objects completely overlapping in space. Michael Della Rocca argues that this possibility is absurd, and therefore PII should be accepted. He claims that the problem with colocated objects lies in the inexplicability of the distinctness of the objects. This inexplicability, he argues, is contrary to the brute fact method of demonstrating the distinctness of objects in counterexamples to PII. Without any other method for demonstrating distinctness of qualitatively indiscernible objects deniers of PII are simply begging the question when they posit the possibility of distinct indiscernibles. I argue in this paper that a clear understanding of the different ways that objects can be colocated removes the counterintuitiveness of colocation, and thereby supports the denial of PII.