This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

Here is a question about mereological simples that I raised in a recent paper.

Richard Cartwright is one of the most clearheaded, astute, and penetrating philosophers in this country. Because of his own strict standards, however, his work has been published only sparingly and is not as well known as he himself is. Philosophical Essays is a welcome first collection. It includes fifteen essays spanning three decades of Cartwright's thought and focusing on central problems in the philosophy of logic, the philosophy of language, and metaphysics. The introduction offers an excellent guide to Cartwright's mode (...) of thought and pedagogical style. Some of these essays are now regarded as classics; six others are published here for the first time. Each of them, from "Macbeth's Dagger" to "Negative Existentials" and "Propositions of Pure Logic" is a model of craftsmanship and clarity of thought. They span a variety of topics, including identity, truths, essence, implication, and philosophical method. Richard Cartwright is Professor of Philosophy and Head of the Department of Linguistics and Philosophy at MIT. (shrink)

Hud Hudson has argued that if MaxCon, Ned Markosian's favored answer to the Simple Question, is true, then there couldn't be gunky objects. If Hudson's argument succeeds, then those who believe that gunky objects are possible have a good reason to reject MaxCon. However, I show that Hudson's argument relies on substantive metaphysical claims that a proponent of MaxCon need not accept. Thus, one who endorses MaxCon need not reject the possibility of gunky objects and those who believe that gunky (...) objects are possible need not reject MaxCon. (shrink)

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)

The concept of a physical object has figured prominently in the history of philosophy, and is probably more important now than it has ever been before. Yet the question What are physical objects?, i.e., What is the correct analysis of the concept of a physical object?, has received surprisingly little attention. The purpose of this paper is to address this question. I consider several attempts at answering the question, and give my reasons for preferring one of them over its rivals. (...) The account of physical objects that I recommend---the Spatial Location Account---defines physical objects as objects with spatial locations. The intuitive idea behind the Spatial Location Account is this. Objects from all of the different ontological categories---physical objects; non-physical objects like souls, if there are any; propositions; universals; etc.---have this much in common: they all exist in time. But not all of them exist in space. The ones that exist in time and space, i.e., the ones that have spatial locations, are the ones that count as physical objects. (shrink)

Something could be round even if it were the only thing in the universe, unaccompanied by anything distinct from itself. Jaegwon Kim once suggested that we define an intrinsic property as one that can belong to something unaccompanied. Wrong: unaccompaniment itself is not intrinsic, yet it can belong to something unaccompanied. But there is a better Kim-style definition. Say that P is independent of accompaniment iff four different cases are possible: something accompanied may have P or lack P, something unaccompanied (...) may have P or lack P. P is basic intrinsic iff (1) P and not-P are nondisjunctive and contingent, and (2) P is independent of accompaniment. Two things (actual or possible) are duplicates iff they have exactly the same basic intrinsic properties. P is intrinsic iff no two duplicates differ with respect to P. (shrink)

This paper sets out a moderate version of metaphysical structural realism that stands in contrast to both the epistemic structural realism of Worrall and the—radical—ontic structural realism of French and Ladyman. According to moderate structural realism, objects and relations (structure) are on the same ontological footing, with the objects being characterized only by the relations in which they stand. We show how this position fares well as regards philosophical arguments, avoiding the objections against the other two versions of structural realism. (...) In particular, we set out how this position can be applied to space-time, providing for a convincing understanding of space-time points in the standard tensor formulation of general relativity as well as in the fibre bundle formulation. (shrink)

This chapter argues that from a particularly weak recombination principle and plausible assumptions about the nature of parthood and location, it follows that it is possible that the mereological structure of the material world and that of space-time fail to correspond to one another in very radical ways. The chapter suggests, moreover, that rejecting the possibility of such failures of correspondence leaves us with a choice of no less unappealing alternatives. It also discusses a few ways in which their possibility (...) is relevant to various important debates in metaphysics. (shrink)

According to Peter van Inwagen, visible inanimate objects do not, strictly speaking, exist. In defending this controversial thesis, he offers fresh insights on such topics as personal identity, commonsense belief, existence over time, the phenomenon of vagueness, and the relation between metaphysics and ordinary language.

This book argues that the only kind of metaphysics that can contribute to objective knowledge is one based specifically on contemporary science as it really is, and not on philosophers' a priori intuitions, common sense, or simplifications of science. In addition to showing how recent metaphysics has drifted away from connection with all other serious scholarly inquiry as a result of not heeding this restriction, this book demonstrates how to build a metaphysics compatible with current fundamental physics, which, when combined (...) with metaphysics of the special sciences, can be used to unify physics with the other sciences without reducing these sciences to physics itself. Taking science metaphysically seriously, this book argues, means that metaphysicians must abandon the picture of the world as composed of self-subsistent individual objects, and the paradigm of causation as the collision of such objects. The text assesses the role of information theory and complex systems theory in attempts to explain the relationship between the special sciences and physics, treading a middle road between the grand synthesis of thermodynamics and information, and eliminativism about information. The consequences of the books' metaphysical theory for central issues in the philosophy of science are explored, including the implications for the realism versus empiricism debate, the role of causation in scientific explanations, the nature of causation and laws, the status of abstract and virtual objects, and the objective reality of natural kinds. (shrink)

I argue that there are is no informative statement of necessary and sufficient conditions for being a mereological simple.

Hud Hudson offers a fascinating examination of philosophical reasons to believe in hyperspace. He explores non-theistic reasons in the first chapter and theistic ones towards the end; in the intervening sections he inquires into a variety of puzzles in the metaphysics of material objects that are either generated by the hypothesis of hyperspace or else informed by it, with discussions of receptacles, boundaries, contact, occupation, and superluminal motion. Anyone engaged with contemporary metaphysics, and many philosophers of religion, will find much (...) to stimulate them here. (shrink)

What are the necessary and jointly sufficient conditions for an object's being a simple (an object without proper parts)? According to one prominent view, The Pointy View of Simples, an object is a simple if and only if the region occupied by that object contains exactly one point in space. According to another prominent view, MaxCon, an object is a simple if and only if it is maximally continuous. In this paper, I argue that both of these views are inconsistent (...) with the possibility of discrete space. I then go on to formulate analogues to these two views that are consistent with this possibility, and argue that if we are willing to grant the possibility of discrete space, we should endorse the analogue to The Pointy View of Simples over the analogue to MaxCon. (shrink)

Since the publication of Peter van Inwagen's book, Material Beings,1 there has been a growing body of philosophical literature on the topic of composition. The main question addressed in both van Inwagen's book and subsequent discussions of the topic is a question that van Inwagen calls "the Special Composition Question." The Special Composition Question is, roughly, the question Under what circumstances do several things compose, or add up to, or form, a single object? For the purposes of formulating a more (...) precise version of the Special Composition Question, we can adopt the following technical terms. (shrink)

It is common for philosophers to offer philosophical accounts or analyses, as they are sometimes called, of knowledge, autonomy, representation, (moral) goodness, reference, and even modesty. These philosophical analyses raise deep questions.What is it that is being analyzed (i.e. what sorts of things are the objects of analysis)? What sort of thing is the analysis itself (a proposition? sentence?)? Under what conditions is an analysis correct? How can a correct analysis be informative? How, if at all, does the production of (...) philosophical analyses differ from what scientists do? The purpose of the present paper is to provide answers to these questions. (shrink)

Hud Hudson presents an innovative view of the metaphysics of human persons according to which human persons are material objects but not human organisms. In developing his account, he formulates and defends a unique collection of positions on parthood, persistence, vagueness, composition, identity, and various puzzles of material constitution. The author also applies his materialist metaphysics to issues in ethics and in the philosophy of religion. He examines the implications for ethics of his metaphysical views for standard arguments addressing the (...) moral permissibility of our treatment of human persons and their parts, fetuses and infants, the irreversibly comatose, and corpses. He argues that his metaphysics provides the best foundation in the philosophy of religion for the Christian doctrine of the resurrection of the body. Hudson addresses a broad range of metaphysical issues, but among his most strikingly original contributions are his defense of the "Partist" view and his argument for the compatibility of Christianity with a materialistic theory of human persons. (shrink)

I argue that from a very weak recombination principle and plausible assumptions about the nature of parthood and location it follows that it's possible that the mereological structure of the material world and that of spacetime fail to correspond to one another in very radical ways. I defend, moreover, that rejecting the possibility of such failures of correspondence leaves us with a choice of equally radical alternatives. I also discuss a few ways in which their possibility is relevant to various (...) debates in metaphysics. (shrink)

This paper looks at the question of what regions of space are possibly exactly occupied by a material object.