One might well wonder—is there a category under which every thing falls? Offering an informative account of such a category is no easy task. For nothing would distinguish things that fall under it from those that don’t—there being, after all, none of the latter. It seems hard, then, to say much about any fully general category; and it would appear to do no carving or categorizing or dividing at all. Nonetheless there are candidates for such a fully general office, including (...) thing, being, entity, item, existent, and—especially—object.[ It is not obvious that there is any fully general category (whether object or otherwise). Accordingly, not all accounts of object assign it to a fully general category, instead allowing that there are non-objects. On those views, object does indeed divide. Accounts of object, then, differ with respect to whether there are non-objects. And this is not the only fault line. Other dimensions of difference include what objects there are and what objects are. Accordingly, this entry will survey three broad questions about the category object: What, if any, is its contrast or complement? What is its extension? What is its nature? (shrink)

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.

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)

According to the Ontological Innocence Thesis (OIT), grounded entities are ontologically innocent relative to their full grounds. I argue that OIT entails a contradiction, and therefore must be discarded. My argument turns on the notion of “groundmates,” two or more numerically distinct entities that share at least one of their full grounds. I argue that, if OIT is true, then it is both the case that there are groundmates and that there are no groundmates. Therefore, so I conclude, OIT is (...) false. Moreover, once we have seen why OIT is false, only three heterodox views about reality's structure remain. So this paper’s second conclusion is that, even after we have discarded OIT, we are in for an additional surprise. (shrink)

The social world contains institutions, groups, objects, and more. This essay explores a puzzle about the essences of social items. There is widespread consensus against social essences because of problematic presuppositions often made about them. But it is argued that essence can be freed from these presuppositions and their problems. Even so, a puzzle still arises. In a Platonic spirit, essences in general seem detached from the world. In an Aristotelian spirit, social essences in particular seem embedded in the world. (...) The puzzle is that these inclinations are individually plausible but jointly incompatible. The essay has four aims: to clarify and refine the puzzle; to explore the puzzle's implications for essence in general and for social essences in particular; to illustrate the fruitfulness of the general distinction between detached and embedded; and to develop this distinction to sketch a novel solution to the puzzle. (shrink)

As there is currently a neo-Aristotelian revival currently taking place within contemporary metaphysics and dispositions, or causal powers are now being routinely utilised in theories of causality and modality, more attention is beginning to be paid to a central Aristotelian concern: the metaphysics of substantial unity, and the doctrine of hylomorphism. In this paper, I distinguish two strands of hylomorphism present in the contemporary literature and argue that not only does each engender unique conceptual difficulties, but neither adequately captures the (...) metaphysics of Aristotelian hylomorphism. Thus both strands of contemporary hylomorphism, I argue, fundamentally misunderstand what substantial unity amounts to in the hylomorphic framework – namely, the metaphysical inseparability of matter and form. (shrink)

Material objects extend through space by having different spatial parts in different places. But how do they persist through time? According to some philosophers, things have temporal parts as well as spatial parts: accepting this is supposed to help us solve a whole bunch of metaphysical problems, and keep our philosophy in line with modern physics. Other philosophers disagree, arguing that neither metaphysics nor physics give us good reason to believe in temporal parts.

Neo‐Aristotelian Plenitude is the thesis that, necessarily, any property that could be had essentially by something or other is had essentially by something or other if and only if and because it is instantiated; any essentializable property is essentialized iff and because it is instantiated. In this paper, I develop a partial nonmodal characterization of ‘essentializable' and show it cannot be transformed into a full characterization. There are several seemingly insurmountable obstacles that any full characterization of essentializability must overcome. Moreover, (...) these obstacles threaten other views in the conceptual neighborhood such as Counterpart Theoretic Plenitude and Conceptualist Plenitude. (shrink)

The idea of “material plenitude” has been gaining traction in recent discussions of the metaphysics of material objects. My main goal here is to show that this idea may have important dialectical implications for the metaphysics of properties – more specifically, that it provides nominalists with new resources in their attempt to reject an ontology of universals. I will recapitulate one of the main arguments against nominalism – due to David Armstrong – and show how plenitude helps the nominalist overcome (...) the argument. (shrink)

A number of prominent metaphysicians have recently defended the idea of material plenitude: wherever there is one material object, there is in fact a great multitude of them, all coincident and sharing many properties, but differing in which of these properties they have essentially and which accidentally. The main goal of this paper is to put on the agenda an important theoretical decision that plenitudinists face, regarding whether their plenitude is egalitarian or elitist, depending on whether or not they take (...) all objects that coincide at a certain location to be in some sense ontologically on a par. Many current proponents of plenitude tend toward egalitarianism. But current proponents often also point to an Aristotelian tradition they claim to carry on; indeed, the view is sometimes referred to as “neo-Aristotelian plenitude.” By examining some of the historical protagonists of Aristotelian plenitude, however, I show that they defended rather an elitist form of plenitude, wherein a single coincident is ontologically privileged in every occupied region. In the final section of the paper, I also try to articulate the basic motivation for each outlook, by way of initiating discussion of which view plenitudinists should believe. (shrink)

As I will use the term, an object is a mereological sum of some things just in case those things compose it simply in virtue of existing. In the first half of this paper, I argue that there are no sums. The key premise for this conclusion relies on a constraint on what, in certain cases, it takes for something to ground, or metaphysically explain, something else. In the second half, I argue that in light of my argument against sums, (...) Universalism, which is perhaps the most widely accepted answer to the Special Composition Question, is false. (shrink)

It is both a matter of everyday experience and a tenet of sociological theory that people often occupy a range of social roles and identities, some of which are associated with mutually incompatible properties. But since nothing could have incompatible properties, it is not clear how this is possible. It has been suggested, notably by Kit Fine (1982, 1999, 2006), that the puzzling relation between a person and their various social roles and identities can be explained by admitting an ontology (...) of social qua objects—objects constituted by, yet distinct from, the persons on which they are based. This article argues that admitting even a rich ontology of such qua objects does not suffice to explain the puzzle cases of interest. Instead, alternative resources are required which, once available, diminish the motivation for adopting an ontology of social qua objects in the first place. The paper concludes by considering whether there remains work for social qua objects in explaining differences in persistence conditions between a person and the social individuals to which they may give rise, but reaches a negative verdict. Social qua objects, if they exist, have little work to do in our theorizing about the relation between a person and their various social roles and identities. (shrink)

Aristotle famously held that objects are comprised of matter and form. That is the central doctrine of hylomorphism (sometimes rendered “hylemorphism”—hyle, matter; morphe, form), and the view has become a live topic of inquiry today. Contemporary proponents of the doctrine include Jeffrey Brower, Kit Fine, David Hershenov, Mark Johnston, Kathrin Koslicki, Anna Marmodoro, Michael Rea, and Patrick Toner, among others. In the wake of these contemporary hylomorphic theories the doctrine has seen application to various topics within mainstream analytic metaphysics. Here, (...) appeals to form and matter are used to shed light on problems about ontology, personal identity, philosophy of mind, and philosophy of religion. The current entry documents this resurgence of interest in hylomorphism, the ways it has been applied, and its reception. (shrink)

The principle of plenitude says that every material object coincides with abundantly many further objects that differ in their modal profiles. A necessarily unmanifested disposition is a disposition that necessarily does not manifest. This paper argues that if the principle of plenitude holds, then there are some necessarily unmanifested dispositions. These necessarily unmanifested dispositions will be argued to evade some objections against the cases of necessarily unmanifested dispositions put forward by Carrie Jenkins and Daniel Nolan.

We summarize in this introduction the contents of all the contributions included in Synthese special issue on form, structure and hylomorphism. Moreover, we provide an exhaustive bibliography of recent research on these topics.

The Problem of Too Many Thinkers is the result, implied by several “permissive” ontologies, that we spatiotemporally overlap with a number of intrinsically person-like entities. The problem, as usually formulated, leaves open a much-neglected question: do we literally share our mental lives, i.e. each of our mental states, with these person-like entities, or do we instead enjoy mental lives that are qualitatively indistinguishable but numerically distinct from theirs? The latter option raises the worry that there is an additional Problem of (...) Too Many Mental Tokens. This paper argues that there is indeed such a problem, at least in fission cases. In the course of articulating this problem, we will make a number of surprising discoveries about the relationship between personal persistence and the metaphysics of mental entities. We will also see that the Problem of Too Many Mental Tokens has significant epistemological and ethical implications, which will haunt us even once we have addressed the Problem of Too Many Thinkers. (shrink)

One of the salient developments in recent metaphysics is the increasing popularity of _material plenitude_: roughly, the thesis that wherever there is one material object there is in fact a great multitude of co-located but numerically distinct objects that differ principally in which of their properties they have essentially and which accidentally. Here I argue that we have at least as much reason to look favorably on _event plenitude_: wherever one event occurs there occur a great multitude of co-located but (...) numerically distinct events that differ principally in which of their properties they have essentially and which accidentally. I argue, first, that the standard reasons to adopt material plenitude extend fairly straightforwardly to events, and secondly, that only event plenitude can protect the plausible idea that causality is an extensional relation. (shrink)

Following in the hylomorphic tradition of Aristotle, Thomas Aquinas holds that all material substances are composed of matter and form. Like Aristotle, Aquinas also recognizes two different types of forms that material substances can be said to possess: substantial forms and accidental forms. Of which form or forms, then, are material substances composed? This paper explores two competing models of Aquinas’s ontology of material substances, which diverge on precisely this issue. According to what the author refers to as the “Standard (...) Model,” Aquinas’s view is that a material substance is composed of prime matter and substantial form. According to the “Expanded Model,” Aquinas’s view is that a material substance is composed of prime matter, substantial form, and all of its accidental forms. After outlining the main claims of each of the two competing models and considering two arguments in favor of the Standard Model, the author offers two arguments in favor of the Expanded Model. He argues that, given the way in which Aquinas argues for God’s simplicity in question three of the Prima pars, and the way in which he consistently describes the difference between an essence and a suppositum, or individual substance, throughout his works, there is good reason to believe that Aquinas thinks that the accidental forms of a material substance are included among its metaphysical parts. (shrink)

In The Principles of Mathematics, Russell writes: Whatever may be an object of thought, or may occur in any true or false proposition, or can be counted as one, I call a term. This, then, is the widest word in the philosophical vocabulary. I shall use as synonymous with it the words unit, individual and entity. The first two emphasize the fact that every term is one, while the third is derived from the fact that every term has being, i.e. (...) is in some sense. A man, a moment, a number, a class, a relation, a chimera, or anything else that can be mentioned, is sure to be a term'. Now in this remark, a certain extremely general, topic-neutral use of ‘object’ is singled out, a use in which the expression is treated as equivalent to (equally neutral) uses of ‘term’, ‘entity’, ‘unit’, ‘individual’, and ‘thing’. In addition, a claim is made to the effect that the content of the expression, with its emphasis on one, is such as to be adequate to comprehend the sum-total of existence, to include whatever there may be. The paper addresses the question of what this claim means, and whether it might be true. (shrink)

Fairchild (2019) advertised the humility of material plenitude, arguing that despite the profligate ontology of coincident objects it entails, the best version of plenitude is one that takes no stand on a range of nearby questions about modality and coincidence. Roughly, the thought is that plenitude says only that there are coincident objects corresponding to every consistent pattern of essential and accidental properties. Plenitude says (or should say) nothing about which patterns those might be, and so should be compatible with (...) any reasonable hypothesis about which combinations of properties it is possible for something to have. I argued in the earlier paper that a particular formulation of the target view (Global Plenitude) has exactly that virtue. But, unfortunately, Global Plenitude turns out not to be very humble at all. Global Plenitude is incompatible with an exceptionally compelling hypothesis about coincidence: that there are some things which coincide, but might not have. Scandal ensues. (shrink)

In his 1991 book, Parts of Classes, David Lewis discusses the idea that composition is identity, alongside the idea that mereological overlap is a form of partial identity. But this notion of partial identity does nothing to help Lewis achieve his goals in that book. So why does he mention it? I explore and resolve this puzzle, by comparing Parts of Classes with Lewis's invocation of partial identity in his 1993 paper ‘Many But Almost One’, where he uses it to (...) address Unger's problem of the many. I raise some concerns about this way of thinking of partial identity, but conclude that, for Lewis, it is an important defence against accusations of ontological profligacy. (shrink)