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)

I first explore the notion of the world's being such that everything in it is a proper part. I then explore the notion of the world's being such that everything in it both is and has a proper part. Given two well recognized assumptions, I argue that both notions represent genuine metaphysical possibilities. Finally I consider, but dismiss, some possible objections.

In this paper I argue that we need to take irreducibly plural logic more seriously in metaphysical debates due to the fact that the verdict of many metaphysical debates hangs on it. I give two examples. The main example I focus on is the debate recently revived by Jonathan Schaffer over the fundamental cardinality of the world. I show how the three main arguments provided by Schaffer are unsound in virtue of an employment of plural logic. The second example I (...) give is a more general issue about the possibility of emergent properties of mereological wholes. Employing plural logic there is a new way to understand such cases. The upshot is that plural logic greatly matters to metaphysics and hence can no longer be ignored the way it has in this area. (shrink)

Many metaphysicians accept the view that, necessarily, any collection of things composes some further thing. Necessarily, my arms, legs, head, and torso compose my body; necessarily, my arms, my heart, and the table compose something y; necessarily, my heart and the sun compose something z; and so on. 1 Though there have been a few recent attempts to argue against the necessity of this principle of unrestricted composition the consensus is that if it is true, it is necessarily true. 2In (...) what follows I will join the few dissenters and argue that this principle of unrestricted composition is not necessarily true. If I am right, it follows that either some principle of restricted composition is necessarily true or the existence of composite objects is a contingent matter. I will end by indicating why the latter option seems the most plausible. 3I proceed by reductio. Assume the following: Unrestricted composition is necessarily true.That is, assume that necessarily, any collection of things composes something. Then, necessarily, the collection of everything composes something. That is, necessarily, there exists a universal object U having all things as parts, not itself being a proper part of anything. Hence, by our assumption, we get: There must be a universal object U.It is important to note that this is so whether the world is finite or infinite. Holding that in worlds of finite cardinality there is a universal object U while in worlds of infinite cardinality there is no universal object U amounts to accepting a restricted form of composition. 4Now consider the following scenario. Everything in this world is spatially extended and just one half of something else that is also spatially extended. That is, for any thing in this world, there is something else of which …. (shrink)

Debates over what is fundamental assume that what is most fundamental must be either a “top” level (roughly, the biggest or highest-level thing), or a “bottom” level (roughly, the smallest or lowest-level things). Here I sketch an alternative to top-ism and bottom-ism, the view that a middle level could be the most fundamental, and argue for its plausibility. I then suggest that the view satisfies the desiderata of asymmetry, irreflexivity, transitivity, and well-foundedness of fundamentality, that the view has explanatory power (...) on par with that of top-ism and bottom-ism, and that it satisfies the Principle of Sufficient Reason. (shrink)

(No abstract is available for this citation).

According to some views of reality, some objects are fundamental and other objects depend for their existence upon these fundamental objects. In this article, I argue that we have reason to reject these views.

The stage theory is a four-dimensional account of persistence motivatedby the worm theory's inability to account for our intuitions in thecases involving coinciding objects. Like the worm theory, it claimsthat there are objects spread out in time, but unlike the worm theory,it argues that these spacetime worms are not familiar particulars liketables and chairs. Rather, familiar particulars are the instantaneoustemporal slices of worms. In order to explain our intuitions that particulars persist for more than an instant, the stage theory drawson (...) the counterpart theory of modal possibilism, which it is supposedto parallel. In this paper I show how the stage theory presupposes thattime can be divided into instants, which I call the atomistic view oftime. I do this by laying out an alternative theory of the nature oftime, the gunky view, and show that if time is gunky the stage theorycollapses into the worm theory. The deeper problem is that the merepossibility of gunky time would cause the stage theory's parallels topossibilism to break down. I therefore conclude that the stage theoryis committed to the view that time is necessarily atomistic. Finally,in the last section I argue that the fact that the stage theory rulesout a priori the possibility of time being gunky gives us reason toreject it as an account of persistence. (shrink)

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)

We often speak of an object being composed of various other objects. We say that the deck is composed of the cards, that a road is the sum total of its sections, that a house is composed of its walls, ceilings, floors, doors, etc. Suppose we have some material objects. Here is a philosophical question: what conditions must obtain for those objects to compose something? In his recent book Material Beings, Peter van Inwagen addresses this question, which he calls the (...) ‘special composition question’; his answer is:1 (1) For any material objects X , the X s compose something iff the activity of the X s constitutes a life, or there is only one of the Xs. Additionally, he accepts a simpler thesis that follows from (1):2 (2) Every material object is either a mereological atom or a living thing, where a mereological atom is an object lacking proper parts. (2) may seem radical. If it is true then there are no tables, chairs, planets, protons, galaxies, gas stations, etc. But van Inwagen does not hold it lightly— there are serious difficulties with alternate views. Moreover, he claims that.. (shrink)

Consider a circle and a pair of its semicircles. Which is prior, the whole or its parts? Are the semicircles dependent abstractions from their whole, or is the circle a derivative construction from its parts? Now in place of the circle consider the entire cosmos (the ultimate concrete whole), and in place of the pair of semicircles consider the myriad particles (the ultimate concrete parts). Which if either is ultimately prior, the one ultimate whole or its many ultimate parts?

The question of what truths are necessary in the broadest possible sense is a difficult one to answer, as is the question of what the limits are to what is possible. (Most people would see these two questions as different sides of the same coin, of course, since many think the question of what is possible is just the question of what is not necessarily ruled out). We have three general sorts of strategies for determining whether something is necessary (or (...) possible). We can identify it in a class that we were previously sure was a class of things that are necessary – we might show it is a theorem of a logical system that we have confidence in, or that the sentence appears to be true simply in virtue of the meanings of the words, or that it is a true statement involving names or about natural kinds of the “necessary a posteriori” sort discussed by Kripke and Putnam, and there are perhaps other classes of claims which we are prepared to accept are necessary if true.1 Likewise, we might establish the possibility of something occurring by reference to a class of well-established or uncontroversial possibilities: e.g. we are inclined to think that it is possible (in the broadest sense) for an event to occur in the future if one of the same kind has occurred in the past. (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)

Not the least admirable of the late David Lewis’s attributes was his disdain for technical terminology and jargon. His writings are a model demonstrating that, with skill and care, it is possible to discuss even the most mathematical aspects of logic and semantics in clear English prose, and with only a minimum of symbolism. The main text of Parts of Classes [1, hereafter: PoC], a 120-page essay on the foundations of set theory, follows Aristotle in using letters as variables, and (...) has a few dashes and ellipses where it mentions schemata, but is otherwise free of logical notation. The essential advantages of what Church called “the logistic method” do not depend on its typographical accidents!) It is only natural that writers following him have taken one of his expressive words and turned it into a technical term: he allowed ‘atomless gunk’ as a possible complication in the mereological analysis of things, and ‘gunk’ is now a technical term in mereology. Gunk is stuff every part of which contains further parts, stuff which can be divided endlessly without ever arriving at an indivisible atom. (shrink)

ABSTRACTA structure is temporally gunky just in case all of its temporal parts have proper temporal parts. Joshua Stuchlik [2003] objects to the stage theory of persistence from temporal gunk by ar...

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)

Fundamental concrete particulars are needed to explain facts about non-fundamental concrete particulars. However, the former can only play this explanatory role if they are properly discernible from the latter. Extant theories of how to discern fundamental concreta primarily concern mereological structure. Those according to which fundamental concreta can bear, but not be, proper parts are motivated by the possibilities that all concreta bear proper parts and that some properties of wholes are not fixed by the properties of their proper parts. (...) In response, theorists who hold that the fundamental concrete particulars can be proper parts may appeal to the possibility that every concrete particular is a proper part—that there is no mereologically maximal whole world, as well as to the intuition that fundamental concreta are qualitatively homogeneous “blocks” from which non-fundamental concreta are built. After motivating the plausibility of gunk and junk, the present essay proposes a constraint on fundamental concrete particulars based on topology instead of mereology: the fundamental concrete particulars must be appropriately connected. This constraint has the unique advantage of consistency with each of gunk, emergence, junk, and the building block intuition. (shrink)

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

Like most theories in first order metaphysics, theories of persistence generally aim at metaphysically necessary truth. Consequently, those that accept proper temporal parts of material entities are maximally competitive only when they accord with the full range of metaphysically possible temporal mereological structures. Consider, for example, a structure in which every element is a proper temporal part of some others. The present essay argues that temporal junk plausibly is possible and that perdurantism, the thesis that material entities persist by having (...) distinct proper temporal parts at distinct times, does not accord with it. The essay then outlines a novel four-dimensionalist theory of persistence that accommodates junk. On this theory, material entities persist not in virtue of possessing proper temporal parts, but rather in virtue of being grounded by certain pluralities of fundamental property instances over their careers, and by sub-pluralities thereof over corresponding sub-intervals of their careers. Accordingly, this way of persisting is dubbed ‘plurdurance’. (shrink)