I argue that metaphysical views of material objects should be understood as 'packages', rather than individual claims, where the other parts of the package include how the theory addresses 'recalcitant data', and that when the packages meet certain general desiderata - which all of the currently competing views *can* meet - there is nothing in the world that could make one of the theories true as opposed to any of the others.

Pluralists about coincident entities say that distinct entities may be spatially coincident throughout their entire existence. The most pressing issue they face is the grounding problem. They say that coincident entities may differ in their persistence conditions and in the sortals they fall under. But how can they differ in these ways, given that they share all their microphysical properties? What grounds those differences, if not their microphysical properties? Do those differences depend only on the way we conceptualise those objects? (...) Are they primitive facts about reality? Neither option is pleasant for the pluralist, but what else can she say? To respond to the grounding problem, the pluralist should first tell a story about what material objects are. If that story explains how the modal and sortal properties of objects are grounded, in a way that allows for differences between coincident objects, then she has a response to the problem. That is precisely my aim in this paper. (shrink)

When do several objects compose a further object? The last twenty years have seen a great deal of discussion of this question. According to the most popular view on the market, there is a physical object composed of your brain and Jeremy Bentham’s body. According to the second-most popular view on the market, there are no such objects as human brains or human bodies, and there are also no atoms, rocks, tables, or stars. And according to the third-ranked view, there (...) are human bodies, but still no brains, atoms, rocks, tables, or stars. Although it’s pleasant to have so many crazy-sounding views around, I think it would also be nice to have a commonsense option available. The aim of this paper is to offer such an option. The approach I offer begins by considering a mereological question other than the standard one that has been the focus of most discussions in the literature. I try to show that the road to mereological sanity begins with giving the most straightforward and commonsensical answer to this other question, and then extending that answer to further questions about the mereology of physical objects. On the approach I am recommending, it turns out that all of the mereological properties and relations of physical objects are determined by their spatial properties and relations. (shrink)

Can there be objects that are ‘thin’ in the sense that very little is required for their existence? A number of philosophers have thought so. For instance, many Fregeans believe it suffices for the existence of directions that there be lines standing in the relation of parallelism; other philosophers believe it suffices for a mathematical theory to have a model that the theory be coherent. This article explains the appeal of thin objects, discusses the three most important strategies for articulating (...) and defending the idea of such objects, and outlines some problems that these strategies face. (shrink)

As is well known, Aristotelian natural philosophy, and many other systems of natural philosophy since, have relied heavily on teleology and teleological causation. Somehow, the purpose or end of an obj ect can be used to predict and explain what that object does: once you know that the end of an acorn is to become an oak, and a few things about what sorts of circumstances are conducive to the attainment of this end, you can predict a lot about the (...) sprouting of the acorn and the subsequent behaviour of the piece of vegetation that results. Once you know that a rock seeks to move towards the centre of the Earth, you gain some insight into why it falls when released, and why it deforms the carpet or foot that it lands on. Once you know that the rabbit seeks to preserve itself, you can predict it will run from the fox. And so on. There are at least three features of Aristotle’s teleology, and more generally of an Aristotelian frame of mind about teleology, that may induce suspicion. One is that an end can serve as a "cause": as well as the sort of causation we all recognize, efficient causation, there are other forms, one of which is teleological causation. However, this can look less odd if we think of causes as things that figure in "because" answers to "why" questions. Whether or not self-preservation, or the rabbit’s continued existence, or something similar, causes the rabbit to run, the reply "because it seeks to continue in existence" certainly makes sense as an answer, or part of an answer, to a question about why it ran from the fox. (At present we are only. (shrink)

Say that some things form a set just in case there is a set whose members are precisely the things in question. For instance, all the inhabitants of New York form a set. So do all the stars in the universe. And so do all the natural numbers. Under what conditions do some things form a set?

According to standard, pre-philosophical intuitions, there are many composite objects in the physical universe. There is, for example, my bicycle, which is composed of various parts - wheels, handlebars, molecules, atoms, etc. Recently, a growing body of philosophical literature has concerned itself with questions about the nature of composition.1 The main question that has been raised about composition is, roughly, this: Under what circumstances do some things compose, or add up to, or form, a single object? It turns out that (...) it is surprisingly difficult to give a satisfactory answer to this question that accords with standard, pre-philosophical intuitions about the universe's composite objects. In fact, the three rival views in response to this question that have received the most support in the literature are (i) that there are no objects composed of two or more parts (which means that there are no stars, chairs, humans, or bicycles);2 (ii) that the only objects composed of two or more parts are living organisms (which still means no stars. (shrink)

Particularists in material-object metaphysics hold that our intuitive judgments about which kinds of things there are and are not are largely correct. One common argument against particularism is the argument from arbitrariness, which turns on the claim that there is no ontologically significant difference between certain of the familiar kinds that we intuitively judge to exist (snowballs, islands, statues, solar systems) and certain of the strange kinds that we intuitively judge not to exist (snowdiscalls, incars, gollyswoggles, the fusion of the (...) my nose and the Eiffel Tower). Particularists frequently respond by conceding that there is no ontologically significant difference and embracing some sort of deflationary metaontology (relativism, constructivism, quantifier variance). I show -- by identifying ontologically significant differences -- that the argument can be resisted without retreating to any sort of deflationary metaontology. (shrink)

It is my aim in this paper to show that the contemporary assimilation of essence to modality is fundamentally misguided and that, as a consequence, the corresponding conception of metaphysics should be given up. It is not my view that the modal account fails to capture anything which might reasonably be called a concept of essence. My point, rather, is that the notion of essence which is of central importance to the metaphysics of identity is not to be understood in (...) modal terms or even to be regarded as extensionally equivalent to a modal notion. The one notion is, if I am right, a highly refined version of the other; it is like a sieve which performs a similar function but with a much finer mesh. (shrink)

A lot of people believe that distinct objects can occupy precisely the same place for the entire time during which they exist. Such people have to provide an answer to the 'grounding problem' – they have to explain how such things, alike in so many ways, nonetheless manage to fall under different sortals, or have different modal properties. I argue in detail that they cannot say that there is anything in virtue of which spatio-temporally coincident things have those properties. However, (...) I also argue that this may not be as bad as it looks, and that there is a way to make sense of the claim that such properties are primitive. (shrink)

Modal Plenitude—the view that, for every empirically adequate modal profile, there is an object whose modal profile it is—is held to be consistent with each of endurantist and perdurantist (three- and four-dimensionalist) views of persistence. Here I show that, because “endurer” and “perdurer” are two substantially different kinds of entity, compossible with each other and consistent with empirical data, Modal Plenitude actually entails a third view about persistence that I call “Persistence Egalitarianism.” In every non-empty spacetime region there are two (...) persisting objects: one that endures through the temporal dimension of that region, and another that perdures through the region. Additionally, if the argument from anthropocentrism makes a strong case for Modal Plenitude, then an equally strong and parallel case supports Persistence Egalitarianism. I close with the meta-semantic consequences of persistence egalitarianism for ordinary object talk. (shrink)

In this introductory chapter to my collection of papers, Modal Matters, I present my tripartite account of reality. First, I endorse a plenitudinous Platonism: for every consistent mathematical theory, there is in reality a mathematical system in which the theory is true. Second, for any way of distributing fundamental qualitative properties over mathematical structures, there is a portion of reality that has that structure with fundamental properties distributed in that way; some of these portions of reality, when isolated, are the (...) possible worlds. Third, there is a fundamental ontological distinction between those portions of reality that are absolutely actual, and those that are merely possible. In the course of developing this account of reality, I sketch my views on logic, mathematics, modality, qualitative character, and actuality. An austere Humeanism that rejects all primitive modality motivates and constrains my views. (shrink)

Précis for a book symposium, with contributions from Meg Wallace, Louis deRosset, and Chris Tillman and Joshua Spencer.

A symposium on my *Objects: Nothing Out of the Ordinary* (2015). In response to Wallace, I attempt to clarify the dialectical and epistemic role that my arguments from counterexamples were meant to play, I provide a limited defense of the comparison to the Gettier examples, and I embrace the comparison to Moorean anti-skeptical arguments. In response to deRosset, I provide a clearer formulation of conservatism, explain how a conservative should think about the interaction between intuition and science, and discuss what (...) conservatives should say about scattered territories, clonal colonies, and arbitrary systems. In response to Tillman and Spencer, I fortify my original presentation of the debunking arguments by clarifying why, even while trees (if they exist) are paradigmatically causal, conservatives are meant to be rationally obstructed from believing that it is trees that are causing our tree beliefs. (shrink)

Material Plenitude is the view that there is an abundance of coincident objects wherever there is any material object. Although plenitude has garnered increased attention from metaphysicians in recent years, it has yet to be well‐understood beyond its slogan from. The goal of this article is to explore a few places for puzzlement about plenitude; in particular, how we ought to motivate and formulate the target view. I'll suggest along the way that an investigation of plenitude is not merely of (...) interest in its own right, but can provide valuable insights into abundant ontologies more generally. (shrink)

According to material plenitude, every material object coincides with an abundance of other material objects that differ in the properties they have essentially and accidentally. Although this kind of plenitude is becoming increasingly popular, it isn't clear how to make sense of the view beyond its slogan form. As I argue, it turns out to be extraordinarily difficult to do so: straightforward attempts are either inconsistent or fail to capture the target idea. Making progress requires us to engage in more (...) delicate metaphysics than we might have expected and, along the way, reveals substantive constraints on the material world. In this article, I argue that any attempt to develop a coherent version of plenitude is subject to two under-appreciated challenges, and I develop a version of plenitude (global plenitude) capable of overcoming both. (shrink)

In his recent book, Daniel Korman contrasts ontological conservatives with permissivists and eliminativists about ontology. Roughly speaking, conservatives admit the existence of ‘ordinary objects' like trees, dogs, and snowballs, but deny the existence of ‘extraordinary objects', like composites of trees and dogs. Eliminativists, on the other hand, deny many or all ordinary objects, while permissivists accept both ordinary and extraordinary objects. Our aim in this paper is to outline some of our reasons for being drawn to permissivism, as well as (...) some of our misgivings about conservative metaphysics. In the first section, we discuss a tempting epistemic line of argument against conservatism. This isn’t a line of argument we find especially promising. Our most basic complaint against conservatism is not that conservatism has poor epistemic standing even if true, but instead that conservatism is weird. We develop this thought in the second part of the paper. In the final section we discuss some larger methodological issues about the project of ontology. (shrink)

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. (shrink)

In recent analytic metaphysics, the view that ‘ordinary inanimate objects such as sticks and stones, tables and chairs, simply do not exist’ has been defended by some noteworthy writers. Thomasson opposes such revisionary ontology in favour of an ontology that is conservative with respect to common sense. The book is written in a straightforward, methodical and down-to-earth style. It is also relatively non-specialized, enabling the author and her readers to approach problems that are often dealt with in isolation in a (...) more unified way.Thomasson's arguments are mainly counter-attacks on six ‘eliminativist’ arguments against ordinary objects. A causal redundancy argument espoused by Trenton Merricks holds that to suppose that there are ordinary objects is to suppose that these objects have distinctive causal powers. However, the casual efficacy of a baseball, for example, is exhausted by that of some suitably arranged …. (shrink)

The Principle of Sufficient Reason states that everything has an explanation. But different notions of explanation yield different versions of this principle. Here a version is formulated in terms of the notion of a “grounding” explanation. Its consequences are then explored, with particular emphasis on the fact that it implies necessitarianism, the view that every truth is necessarily true. Finally, the principle is defended from a number of objections, including objections to necessitarianism. The result is a defense of a “rationalist” (...) metaphysics, one that constitutes an alternative to the contemporary dogmas that some aspects of the world are “metaphysically brute” and that the world could in so many ways have been different. (shrink)

I am a realist of a metaphysical stripe. I believe in an immense realm of "modal" and "abstract" entities, of entities that are neither part of, nor stand in any causal relation to, the actual, concrete world. For starters: I believe in possible worlds and individuals; in propositions, properties, and relations (both abundantly and sparsely conceived); in mathematical objects and structures; and in sets (or classes) of whatever I believe in. Call these sorts of entity, and the reality they comprise, (...) metaphysical. In contrast, call the actual, concrete entities, and the reality they comprise, physical. Physical and metaphysical reality together comprise all that there is. In this paper, it is not my aim to defend realism about any particular metaphysical sort of entity. Rather, I ask quite generally whether and how any brand of realism about metaphysical sorts of entity could be justified? (shrink)

‘Restricted composition’ says that there are some composite objects. And it says that some objects jointly compose nothing at all. The main threat to restricted composition is the influential and widely defended Vagueness Argument. We shall see that the Vagueness Argument fails. In seeing how this argument fails, we shall discover a new focus for the debate over composition's extent.

According to Principles of Sufficient Reason, every truth (in some relevant group) has an explanation. One of the most popular defenses of Principles of Sufficient Reason has been the presupposition of reason defense, which takes endorsement of the defended PSR to play a crucial role in our theory selection. According to recent presentations of this defense, our method of theory selection often depends on the assumption that, if a given proposition is true, then it has an explanation, and this will (...) only be justified if we think this holds for all propositions in the relevant group. I argue that this argument fails even when restricted to contingent propositions, and even if we grant that there is no non-arbitrary way to divide true propositions that have explanations from those that lack them. Further, we can give an alternate explanation of what justifies our selecting theories on the basis of explanatory features: the crucial role is not played by an endorsement of a PSR, but rather by our belief that, prima facie, we should prefer theories that exemplify explanatory power to greater degrees than their rivals. This guides our theory selection in a manner similar to ontological parsimony and theoretical simplicity. Unlike a PSR, our belief about explanatory power gives us a prima facie guiding principle, which provides justification in the cases where we think we have it, and not in the cases where we think we don't. (shrink)

Universalism (the thesis that for any ys, those ys compose a further object) is an answer to the Special Composition Question. In the literature there are three arguments – what I call the arguments from elegance – that universalists often rely upon, but which are rarely examined in-depth. I argue that these motivations cannot be had by the perdurantist, for to avoid a commitment to badly behaved superluminal objects perdurantists must answer the ‘Proper Continuant Question’. Any answer to that question (...) necessarily ensures that there is a restricted answer to the Special Composition Question that is just as elegant as universalism. Thus, if you are a perdurantist, the arguments from elegance fail to motivate universalism for there will always be a restricted composition that is just as good. (shrink)

(1) Abstract objects. The nominalist (as the label is used today) denies that there exist abstract objects. The platonist holds that there are abstract objects. One example is numbers. The nominalist denies that there are numbers; the platonist typically affirms it.

Neo-Fregeanism in the philosophy of mathematics consists of two main parts: the logicist thesis, that mathematics (or at least branches thereof, like arithmetic) all but reduce to logic, and the platonist thesis, that there are abstract, mathematical objects. I will here focus on the ontological thesis, platonism. Neo-Fregeanism has been widely discussed in recent years. Mostly the discussion has focused on issues specific to mathematics. I will here single out for special attention the view on ontology which underlies the neo-Fregeans’ (...) claims about mathematical objects, and discuss this view in a broader setting. (shrink)

NeoFregeanism is an intriguing but elusive philosophy of mathematical existence. At crucial points, it goes cryptic and metaphorical. I want to put forward an interpretation of neoFregeanism—perhaps not one that actual neoFregeans will embrace—that makes sense of much of what they say. NeoFregeans should embrace quantifier variance.

In his paper in the same volume, Sider argues that, of maximalism and quantifier variance, the latter promises to let us make better sense of neo-Fregeanism. I argue that neo-Fregeans should, and seemingly do, reject quantifier variance. If they must choose between these two options, they should choose maximalism.

Precis of my book by this title, for a symposium.

In Ordinary Objects, Thomasson pursues an integrated conception of ontology and metaontology. In ontology, she defends the existence of shoes, ships, and other ordinary objects. In metaontology, she defends a deflationary view of ontological inquiry, designed to suck the air out of arguments against ordinary objects. The result is an elegant and insightful defense of a common sense worldview. I am sympathetic—in spirit if not always in letter—with Thomasson’s ontology. But I am skeptical of her deflationary metaontology.

In this paper I respond to Trenton Merricks's (2005) paper ‘Composition and Vagueness’. I argue that Merricks's paper faces the following difficulty: he claims to provide independent motivation for denying one of the premisses of the Lewis-Sider vagueness argument for unrestricted composition, but the alleged motivation he provides begs the question.