An encyclopedia entry which covers various revisionary conceptions of which macroscopic objects there are, and the puzzles and arguments that motivate these conceptions: sorites arguments, the argument from vagueness, the puzzles of material constitution, arguments against indeterminate identity, arguments from arbitrariness, debunking arguments, the overdetermination argument, and the problem of the many.

The Vagueness Argument for universalism only works if you think there is a good reason not to endorse nihilism. Sider's argument from the possibility of gunk is one of the more popular reasons. Further, Hawley has given an argument for the necessity of everything being either gunky or composed of mereological simples. I argue that Hawley's argument rests on the same premise as Sider's argument for the possibility of gunk. Further, I argue that that premise can be used to demonstrate (...) the possibility of simples. Once you stick it all together, you get an absurd consequence. I then survey the possible lessons we could draw from this, arguing that whichever one you take yields an interesting result. (shrink)

Are there any non‐composite objects? Are there any objects every part of which is composite? Are items of either kind even possible? What would they be like? Of what significance would they be? How best can we come to have reasonable beliefs about the answers to these inquiries? Such questions – about the actuality and possibility, the analysis and significance, the methodology and epistemology of simples and pieces of gunk – have been center stage in recent contemporary analytic metaphysics. The (...) following article provides a general overview of some of the current debates on their proper answers as well as a pair of slightly more detailed investigations into two issues of special interest in the recent literature devoted to these topics. (shrink)

Mereological nihilism is the view that no objects have proper parts. Despite how counter‐intuitive it is, it is taken quite seriously, largely because it solves a number of puzzles in the metaphysics of material objects – or so its proponents claim. In this article, I show that for every puzzle that mereological nihilism solves, there is a similar puzzle that (a) it doesn’t solve, and (b) every other solution to the original puzzle does solve. Since the solutions to the new (...) puzzles apply just as well to the old puzzles, the old puzzles provide no motivation to be a mereological nihilist. (shrink)

An object is a simple if and only if it has no proper parts. An object is gunk if and only if every proper part of that object itself has a proper part. In my dissertation, I address the following questions. The concepts of simples and gunk presuppose the concept of parthood. What is the status of this concept? his question itself divides into the following: does the concept of parthood have universal applicability, so that, just as every object is (...) self-identical, every object has parts? Finally, is the concept of parthood univocal, or are there different notions of parthood, each of which is defined on distinct ontological categories? I argue that the concept of parthood has univocal. I also argue that there is some evidence that the concept of parthood has universal applicability. I address the Simple Question, which is “under what circumstances is it true of some object that it has no proper parts?” I argue against several popular answers to the Simple Question, such as the view that simples are all and only point-sized objects, and the view that simples are maximally continuous material objects. I defend the Brutal View, which holds that there is no true, finitely expressible, and informative answer to the Simple Question. In short, there is no criterion for being a simple. Along the way, I address the question of whether extended simples, i.e., simples that are extended in space, are possible. I argue that one popular argument against the possibility of extended simples is unsound. I address the question of whether both simples and gunk are possible. I argue that it is metaphysically possible that material objects be composed of gunk. (shrink)

This paper consists of two parts. The first concerns the logic of vagueness. The second concerns a prominent debate in metaphysics. One of the most widely accepted principles governing the ‘definitely’ operator is the principle of Distribution: if ‘p’ and ‘if p then q’ are both definite, then so is ‘q’. I argue however, that epistemicists about vagueness should reject this principle. The discussion also helps to shed light on the elusive question of what, on this framework, it takes for (...) a sentence to be borderline or definite. In the second part of the paper, I apply this result to a prominent debate in metaphysics. One of the most influential arguments in favour of Universalism about composition is the Lewis-Sider argument from vagueness. An interesting question, however, is whether epistemicists have any particular reasons to resist the argument. I show that there is no obvious reason why epistemicists should resist the argument but there is a non-obvious one: the rejection of Distribution argued for in the first part of the paper provides epistemicists with a unique way of resisting the argument from vagueness. (shrink)

It is often assumed that indeterminacy in mereological relations—in particular, indeterminacy in which collections of objects have fusions—leads immediately to indeterminacy in what objects there are in the world. This assumption is generally taken as a reason for rejecting mereological vagueness. The purpose of this paper is to examine the link between mereological vagueness and existential vagueness. I hope to show that the connection between the two forms of vagueness is not nearly so clear-cut as has been supposed.

The Argument from Vagueness for Universalism contends that any non-arbitrary restriction on composition must be vague, but that vague composition leads to unacceptable count indeterminacy. One common response to the argument is that borderline cases of composition don’t necessarily lead to count indeterminacy because a determinately existing thing may be a borderline case of a presently existing concrete composite object. We can collectively refer to such views as versions of the Status Response. This paper argues that the Status Response cannot (...) handle count indeterminacy about various categories of things, such as events, states of affairs, tropes, holes, shadows, and created abstracta, when these are understood in the right way. This makes the Status Response objectionablfy ad hoc, which should lead us to look for alternative ways of resisting the Argument from Vagueness. (shrink)

The Special Composition Question asks under what conditions a plurality of objects form another, composite object. We propose a condition grounded in our scientific knowledge of physical reality, the essence of which is that objects form a composite object when and only when they are in a bound state – whence our Bound State Proposal. We provide a variety of reasons in favour of a mereological theory that accommodates our Proposal. We consider but reject another proposal, which is quantum-physical in (...) nature: the Entanglement Proposal. We close by responding to Teller’s ‘Suit Objection’. (shrink)