Einar Bohn has argued that principles of composition must be contingent if gunky objects and junky worlds are both metaphysically possible. This paper critically examines such a case for contingentism about composition. I argue that weak mereological universalism, the principle that any two objects compose something, is consistent with the metaphysical possibility of both gunky objects and junky worlds. I further argue that, contra A. J. Cotnoir, the weak mereological universalist can accept a plausible mereological remainder axiom. The proponent of (...) contingent composition will have to look elsewhere for an argument in favor of his position. (shrink)

A mereological structure is junky if and only if each of its elements is a proper part of some other. The young literature on junk has focused on junky worlds and whether they are counterexamples to unrestricted composition. The present note defends the possibility of junky structures that are not worlds. This possibility complicates a recent attempt in the literature to render junk consistent with a weakened form of unrestricted composition. The upshot is that junky non-worlds threaten the weakened form (...) of unrestricted composition as much as junky worlds threaten the traditional version. (shrink)

Those who accept the necessity of mereological universalism face what has come to be known as the ‘junk argument’ due to Bohn [2009], which proceeds from the incompatibility of junk with universalism and the possibility of junk, to conclude that mereological universalism isn't metaphysically necessary. Most attention has focused on ; however, recent authors have cast doubt on . This paper undertakes a defence of premise against three main objections. The first is a new objection to the effect that Bohn's (...) defence of that premise presupposes far too much. I show that one can defend premise from a much weaker set of assumptions. The second objection, due to Contessa [2012], is that those who accept unrestricted composition should only accept the existence of binary sums rather than infinitary fusions. I argue that this conception of unrestricted composition is problematic: it is in conflict with an intuitive remainder principle. The final objection is .. (shrink)

The paper presents different arguments against the necessity of mereological universalism. First, it argues that they are examples of a much more general argumentative structure. It then contends that some of these arguments cannot be resisted by distinguishing different variants of universalism that have been recently proposed in the literature—in contrast with recent suggestions to the contrary. Finally, it provides different ways to resist such contingentist arguments on behalf of universalists.

The paper presents different arguments against the necessity of mereological universalism. First, it argues that they are examples of a much more general argumentative structure. It then contends that some of these arguments cannot be resisted by distinguishing different variants of universalism that have been recently proposed in the literature—in contrast with recent suggestions to the contrary. Finally, it provides different ways to resist such contingentist arguments on behalf of universalists.

An overview of contemporary part-whole theories, with reference to both their axiomatic developments and their philosophical underpinnings.