Theodore Sider

Most facts of grounding involve nonfundamental concepts, and thus must themselves be grounded. But how? The leading approaches—due to Bennett, deRosset, and Dagupta—are subject to objections. The way forward is to deny a presupposition common to the leading approaches, that there must be some simple formula governing how grounding facts are grounded. Everyone agrees that facts about cities might be grounded in some complex way about which we know little; we should say the same about the facts of grounding themselves. The kinds of facts that might enter into the grounds of the facts of grounding are explored at length.

Personal identity is not always symmetric: even if I will not be a later person, the later person may have been me. What makes this possible is that the relations that are criterial of personal identity---such as memory and anticipation---are asymmetric and "count in favor of personal identity from one side only". Asymmetric personal identity can be accommodated by temporal counterpart theory but not by Lewisian overlapping aggregates of person stages. The question of uncertainty in cases of personal fission (and in Everettian quantum mechanics) is also discussed.

According to Ross Cameron's version of the moving spotlight theory of time, (1) Past and future entities exist; (2) the properties and relations they have are those they have now; but nevertheless (3) there are no fundamental past- or future-tensed facts; instead, tensed facts are made true by fundamental facts about the possession of temporal distributional properties and facts about how old things are. I argue that the account isn't sufficiently distinct from the B-theory to fit the usual A-theorist's tastes and arguments, since i) like the traditional spotlight it consists of a B-theoretic metaphysics with one small A-theoretic element tacked on, and since ii) in a sense it does not admit fundamental change. I also argue that the proposed grounding of tensed facts in tenseless facts does not work in certain cases.

Act Utilitarianisms divide into Total and Average versions. Total versions seem to imply Parfit’s “Repugnant Conclusion”. Average versions are proposed in part to avoid the Repugnant Conclusion, but these are subject to “Mere Addition” arguments as detailed by Hudson in “The Diminishing Marginal Value of Happy People”. Thus, various intermediate versions of utilitarianism, such as the one investigated by Hurka in “Value and Population Size”, take on interest. But Hudson argues that such compromise theories are subject to the mere addition arguments, and are therefore no improvement over Average Utilitarianism. I disagree: some such compromise solutions escape Hudson’s Mere Addition arguments.

In my book Four-dimensionalism (chapter 4, section 9), I argued that fourdimensionalism – the doctrine of temporal parts – follows from several other premises, chief among which is the premise that existence is never vague. Kathrin Koslicki (preceding article) claims that the argument fails since its crucial premise is unsupported, and is dialectically inappropriate to assume in the context of arguing for four-dimensionalism. Since the relationship between four-dimensionalism and the non-vagueness of existence is not perfectly transparent, I think the argument would retain some interest even if the premise were wholly unsupported; it would show that anyone who accepts that premise (which seems reasonable enough to me though perhaps not to others) must accept four-dimensionalism. Still, Koslicki is right that my defense of the premise was thin. So I will now try to do better. The new defense will have further premises, which could ultimately be rejected by opponents of four-dimensionalism, and so the argument retains the form: anyone who thinks certain things (which seem reasonable enough to me though perhaps not to others) must believe four-dimensionalism. But that’s metaphysics for you. I should also say that, in addition to the material on vague existence, there is more in Koslicki’s excellent paper which I cannot discuss here. I agree with much of it;1 and where we disagree there are formidable challenges, some of which I hope to address in the future

According to four dimensionalism, the material world is divided into momentary stages. In a four-dimensional world, which objects are the ordinary things, the things we normally name and quantify over? Aggregates of stages, according to most four-dimensionalists, but according to stage theorists (or exdurantists), ordinary objects are instead to be identified with the stages themselves. (A temporal counterpart theoretic account of de re temporal predication is then given.) This paper argues that a stage theorist is best positioned to accept David Lewis's argument from temporary intrinsics for four-dimensionalism, since stage theorists are the only four-dimensionalists who attribute monadic temporary intrinsic properties to ordinary things.

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..

Logic for Philosophy is an introduction to logic for students of contemporary philosophy. It is suitable both for advanced undergraduates and for beginning graduate students in philosophy. It covers (i) basic approaches to logic, including proof theory and especially model theory, (ii) extensions of standard logic that are important in philosophy, and (iii) some elementary philosophy of logic. It emphasizes breadth rather than depth. For example, it discusses modal logic and counterfactuals, but does not prove the central metalogical results for predicate logic (completeness, undecidability, etc.) Its goal is to introduce students to the logic they need to know in order to read contemporary philosophical work. It is very user-friendly for students without an extensive background in mathematics. In short, this book gives you the understanding of logic that you need to do philosophy.

For most us, learning which quantum theory correctly describes human bodies will not affect our attitudes towards our loved ones. On the other hand, a child’s discovery of the nature of meat (or an adult’s discovery of the nature of soylent green) can have a great effect. In still other cases, it is hard to say how one would, or should, react to new information about the underlying nature of what we value—think of how mixed our reactions are to evidence of cultural determinism or atheism, or of how mixed our reactions would be to learning that we all live in the Matrix. (Indeed, maybe there is no objective fact about how we should react. Derek Parfit’s (1984, section 95) fear of death diminished when he became convinced of certain theses about the metaphysics of personal identity. Perhaps there is no objective fact of the matter as to whether this was rational; perhaps it was rational for him but would not be for others.) What can metaphysics contribute to the question of the evil of death? It cannot, on its own, settle the question, since there is no simple rule telling us how to adjust value in light of new information about underlying nature. Given a clear view of the nature of death, there will remain the question of its disvalue. However, metaphysics can help us attain this clear view. Moreover, a clear conception of what metaphysical positions do and don’t say, and a clear conception of how metaphysics works in general, can remove impediments to a rational appraisal of the evil of death.

"Composition as identity" is the radical claim that the whole is identical to the parts - radical because it implies that a single object can be identical to many objects. Composition as identity, together with auxiliary assumptions, implies the principle of "collapse": an object is one of some things if and only it is part of the fusion of those things. Collapse has important implications: the comprehension principle of plural logic must be restricted, plural definite descriptions such as "the Cheerios in the bowl" are empty, Composition as identity does not preclude emergent properties (contrary to what McDaniel has argued), and drastic simplifications of mereological and logical ideology are extensionally available.

I am now typing on a computer I bought two years ago. The computer I bought is identical to the computer on which I type. My computer persists over time. Let us divide our subject matter in two. There is first the question of criteria of identity, the conditions governing when an object of a certain kind, a computer for instance, persists until some later time. There are secondly very general questions about the nature of persistence itself. Here I include the question of temporal parts, as well as certain familiar paradoxes (e.g., the statue and the lump). Following John Perry (1975, Introduction), let us characterize a criterion of identity over time for F s as a way of filling in φ in the following schema: Stages S1 and S2 belong to some continuing F iff φ Defenders of temporal parts (see below) regard S1 and S2 as being temporal parts of the continuing F ; others regard S1 and S2 as different stages in the life history of the continuing F . Thus each camp can make use of Perry’s formula. It is traditional to divide such criteria into those governing persons and those governing anything else. It is further traditional to say that the criterion of identity over time for non-persons involves spatiotemporal continuity. An excellent discussion is Eli Hirsch’s The Concept of Identity1, which utilizes the notion of continuity under a sortal. Kind-terms, or sortals, are terms that specify what kind of or sort of thing an object is. Examples include ‘tree’, ‘car’, and ‘mountain’. Where F is a sortal, Hirsch’s analysis is roughly that stages belong to the same F iff they are connected by a spatiotemporally and qualitatively continuous sequence of F -stages. Unmodified, this analysis prohibits temporally discontinuous entities, such as a watch that is taken apart and then reassembled. Hirsch discusses the necessary modifications. Spatiotemporal continuity analyses face a problem when applied to the persistence of matter. The literature here has been dominated by discussion of examples provided by David Armstrong (1980) and Saul Kripke (unpublished....

In an article in Scientific American (March 1994, pp. 68–74) entitled “The Quantum Physics of Time Travel”, Oxford physicist David Deutsch and Oxford philosopher Michael Lockwood give a defense of the physical possibility of time travel based on the “Many Worlds” interpretation of quantum mechanics. This positive view of theirs is not my concern, however—I want to quarrel with their argument that time travel cannot be accommodated in any other way.1 The best way to spell out the traditional “grandfather paradox” that appears to threaten the possibility of time travel involves the notion of ability, or personal possibility, or free will. An example of David Lewis’s: Tim travels back in time with the intent to kill his grandfather.2 Let us fix the case as one in which Tim in fact will not kill Grandfather; still, it seems that he can kill Grandfather because he is a good shot, has a gun, and is alone with Grandfather at close range. As Lewis says, Tim “has what it takes” to kill Grandfather. However, it is also compelling that Tim cannot kill Grandfather, because if Grandfather had been killed in his youth, Tim would not have existed to kill him. It is important to realize that the paradox essentially involves the notion of ability. No inconsistency results from supposing that Tim does not kill Grandfather. As for the case in which Tim does kill Grandfather, there are various possibilities. We could tell a consistent time travel story in which Tim kills Grandfather, but Grandfather is miraculously resurrected. Or one in which Tim kills Grandfather, but in which Grandfather has already had a child. Or one in which Tim kills Grandfather permanently, before Grandfather has any children, but in which Tim’s grandfather is someone other than Grandfather. As for the story in which Tim both kills Grandfather permanently in such a way that Grandfather has no children, and also is descended from Grandfather, this is an inconsistent time travel story; but of course the existence of some....

is an important principle, worthy of serious scrutiny. Its truth or falsity bears on the question of whether moral rightness, obligatoriness, etc., are a matter of factors “internal” to an agent, or whether “external” factors are relevant to determining the moral normative status of acts. Moreover, Access enjoys considerable intuitive support. If I destroy Greensboro in professor Sorensen’s example by pushing the wrong button, I seem to have a good excuse to give to anyone who would accuse me of wrongdoing: “I had no way of knowing that this action would be wrong!” But if I have a good excuse, then pushing the button doesn’t seem wrong; and if that action isn’t wrong, then I had no obligation to refrain from pushing that button. A principle distinct from, but analogous to, Access also deserves our attention

Peter Forrest and D.M. Armstrong have given an argument against a theory of naturalness proposed by David Lewis based on the fact that ordered pairs can be constructed from sets in any of a number of different ways. 1. I think the argument is good, but requires a more thorough defense. Moreover, the argument has important consequences that have not been noticed. I introduce a version of Lewis’s proposal in section one, and then in section two I present and defend my version of the argument. After addressing a worry about my argument in section three, in section four I argue that a similar “argument from arbitrariness” jeopardizes Lewis’s solution to the Kripke/Wittgenstein puzzle of the content of thought.

Some contemporary Russellians, defenders of the view that the semantic content of a proper name, demonstrative or indexical is simply its referent, are prepared to accept that view’s most infamous apparent consequence: that coreferential names, demonstratives, indexicals, etc. are intersubstitutable salva veritate, even in intentional contexts. Nathan Salmon and Scott Soames argue that our recalcitrant intuitions with respect to the famous apparent counterexamples are not semantic intuitions, but rather pragmatic intuitions. Strictly and literally speaking, Lois Lane believes, and even knows that Clark Kent is identical to Superman, since she believes and knows that Superman is identical to Superman. Salmon and Soames attempt to soften our reaction to this shocker by allowing that it is typically misleading to utter the sentence ‘Lois Lane knows that Clark Kent is identical to Superman’, since it pragmatically implicates, without semantically entailing, that Lois Lane would accept the sentence ‘Clark Kent is identical to Superman’. Our compulsive tendency to claim that ‘Lois Lane knows that Clark Kent is Superman’ is false, rather than merely misleading, is due to a confusion between semantics and pragmatics, between truth conditions and conditions of appropriateness of utterance.1 It is probably fair to say that the common reaction to this move in defense of Russellianism is negative. Mark Richard says the following.

The existence and importance of supervenience principles for identity across times and worlds have been noted, but insufficient attention has been paid to their precise nature. Such attention is repaid with philosophical dividends. The issues in the formulation of the supervenience principles are two. The first involves the relevant variety of supervenience: that variety is global, but there are in fact two versions of global supervenience that must be distinguished. The second involves the subject matter: the names “identity over time” and “identity across worlds” are misnomers, for in neither case is identity at issue. The philosophical dividends then follow. Nathan Salmon’s argument that identity over time needs no “grounds” in matters of qualitative fact can be answered, as can an argument offered by many, that coincident objects would require objectionably ungrounded differences in identities across times and worlds

Elizabeth Barnes and Mari Mikkola raise the important question of whether certain recent approaches to metaphysics exclude feminist metaphysics. My own approach does not, or so I argue. I do define “substantive” questions in terms of fundamentality; and the concepts of feminist metaphysics are nonfundamental. But my definition does not count a question as being nonsubstantive simply because it involves nonfundamental concepts. Questions about the causal structure of the world, including the causal structure of the social world, are generally substantive because their answers are not sensitive to any alternate, equally good conceptual choices we could have made. I also argue that such questions are substantive regardless of the ontology of social kinds.

One often hears a complaint about “bare particulars”. This complaint has bugged me for years. I know it bugs others too, but no one seems to have vented in print, so that is what I propose to do. (I hope also to say a few constructive things along the way.) The complaint is aimed at the substratum theory, which says that particulars are, in a certain sense, separate from their universals. If universals and particulars are separate, connected to each other only by a relation of instantiation, then, it is said, the nature of these particulars becomes mysterious. In themselves, they do not have any properties at all. They are nothing but a pincushion into which universals may be poked. They are Locke’s “I know not what” (1689, II, xxiii, §2); they are Plato’s receptacles (Timaeus 48c–53c); they are “bare particulars”.1 Against substratum theory there is the bundle theory, according to which particulars are just bundles of universals. The substratum and bundle theories agree on much. They agree that both universals and particulars exist. And they agree that a particular in some sense has universals. (I use phrases like ‘particular P has universal U ’ and ‘particular P ’s universals’ neutrally as between the substratum and bundle theories.) But the bundle theory says that a particular is exhaustively composed of (i.e., is a mereological fusion of) its universals. The substratum theory, on the other hand, denies this. Take a particular, and mereologically subtract away its universals. Is anything left? According to the bundle theory, no. But according to the substratum theory, something is indeed left. Call this remaining something a thin particular. The thin particular does not contain the universals as parts; it instantiates them

Recent discussions of consequentialism have drawn our attention to the so-called “self-other” asymmetry. Various cases presented by Michael Slote and Michael Stocker are alleged to demonstrate a fundamental asymmetry between our obligations to others and ourselves.1 Moreover, these cases are taken to constitute a difficulty for consequentialism, and for the various versions of utilitarianism in particular. I agree that there is a fundamental asymmetry between our obligations to ourselves and to others, and that this fact is inconsistent with the letter of traditional utilitarianisms. However, I do not think this represents a deep shortcoming of the spirit behind utilitarianism. In this paper I will argue that the self-other asymmetry can be accommodated in a broadly utilitarian framework. First, in section one, I characterize moral “asymmetry” in general. Then, in section two, I argue that the cases presented by Slote and Stocker do indeed represent a genuine self-other asymmetry. In part, this involves criticism of an attempt to accommodate the asymmetry within a preferentist framework. Finally, I will present my own solution to the problem of self and other

Eternalists say that non-present entities (for instance dinosaurs) exist; presentists say that they do not. But some sceptics deny that this debate is genuine, claiming that presentists simply represent eternalists' quantifiers over non-present entities in different notation. This scepticism may be refuted on purely logical grounds: one of the leading candidate ‘presentist quantifiers’ over non-present things has the inferential role of a quantifier. The dispute over whether non-present objects exist is as genuine and non-verbal as the dispute over whether there is life on other planets.

This note is to show that a well-known point about David Lewis’s (1986) modal realism applies to Timothy Williamson’s (1998; 2002) theory of necessary existents as well.1 Each theory, together with certain “recombination” principles, generates individuals too numerous to form a set. The simplest version of the argument comes from Daniel Nolan (1996).2 Assume the following recombination principle: for each cardinal number, ν, it’s possible that there exist ν nonsets. Then given Lewis’s modal realism it follows that there can be no set of all (that is, Absolutely All) the nonsets. For suppose for reductio that there were such a set, A; let ν be A’s cardinality; and let µ be any cardinal number larger than ν. By the recombination principle, it’s possible that there exist µ nonsets; by modal realism, there exists a possible world containing, as parts, µ nonsets; each of these nonsets is a member of A