A Paradox of Matter and Form

In the face of the puzzles of material constitution, some philosophers have been moved to posit a distinction between an object's matter and its form. A familiar difficulty for contemporary hylomorphism is to say which properties are eligible as forms: for example, it seems that it would be intolerably arbitrary to say that being statue shaped is embodied by some material object, but that other complex shape properties aren't. Anti-arbitrariness concerns lead quickly to a plenitudinous ontology. The usual complaint is that the super-abundance of material objects is too extraordinary to accept, but I want to raise a different worry: I argue that the most natural way of developing this picture is already inconsistent. I show that a simple version of plenitudinous hylomorphism is subject to a Russellian argument, but argue that we cannot treat the problem straightforwardly as an instance of Russell's Paradox of Sets.