Mereological Principles in Metaphysics

Abstract

The relevance of mereology for metaphysics is a perennial theme. In particular, the part-whole relation is applied recently to colocated qua-objects of different sortals: say, a statue and its constituting piece of clay. K. Koslicki (2008. The structure of objects. Oxford: Oxford University Press) claims that only the lump is part of the statue; moreover, its proper part, but not vice versa since the statue has an immaterial part not shared by the lump. She backs her claim by appealing to the weak supplementation principle (WSP). M. Donnelly (2011. "Using mereological principles to support metaphysics." The philosophical quarterly 61:225-46) is critical with the asymmetry argument. I point out that the asymmetry argument trades on the equivocity of the very notion of "part". In the Aristotelian-scholastic tradition Koslicki's neoAristotelianism appeals to, "part" shows up with various meanings not all of them admitting the mereological reading of "part" her argument hinges on. With her argument, the absurd consequence ensues that the lump can also be shown to have an immaterial part not shared by the statue. I show that the presumed immaterial parts cannot be proper parts of composites, only their improper parts. Thus they fail to fall under (WSP). My ultimate goal is to disentangle the mereological and the metaphysical threads by showing what goes with what without taking sides either with the mereologist or the traditional metaphysician.