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.

Persistence through time is like extension through space. A road has spatial parts in the subregions of the region of space it occupies; likewise, an object that exists in time has temporal parts in the various subregions of the total region of time it occupies. This view — known variously as four dimensionalism, the doctrine of temporal parts, and the theory that objects “perdure” — is opposed to “three dimensionalism”, the doctrine that things “endure”, or are “wholly present”.1 I will (...) attempt to resolve this dispute in favor of four dimensionalism by means of a novel argument based on considerations of vagueness. But before argument in this area can be productive, I believe we must become much clearer than is customary about exactly what the dispute is, for the usual ways of formulating the dispute are flawed, especially where three dimensionalism is concerned. (shrink)

First published in 1978, this reissue presents a seminal philosophical work by professor Putnam, in which he puts forward a conception of knowledge which makes ethics, practical knowledge and non-mathematic parts of the social sciences just as much parts of 'knowledge' as the sciences themselves. He also rejects the idea that knowledge can be demarcated from non-knowledge by the fact that the former alone adheres to 'the scientific method'. The first part of the book consists of Professor Putnam's John Locke (...) lectures, delivered at the University of Oxford in 1976, offering a detailed examination of a 'physicalist' theory of reference against a background of the works of Tarski, Carnap, Popper, Hempel and Kant. The analysis then extends to notions of truth, the character of linguistic enquiry and social scientific enquiry in general, interconnecting with the great metaphysical problem of realism, the nature of language and reference, and the character of ourselves. (shrink)

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

This anthology introduces advanced undergraduates and beginning graduate students to today's debates in metaphysics. The book consists of essays by contemporary metaphysicians, and all but one appear here for the first time. For each of nine topics, there are two essays, one "pro-" and one "con-".

Two main claims are defended in this paper: first, that typical disputes in the literature about the ontology of physical objects are merely verbal; second, that the proper way to resolve these disputes is by appealing to common sense or ordinary language. A verbal dispute is characterized not in terms of private idiolects, but in terms of different linguistic communities representing different positions. If we imagine a community that makes Chisholm's mereological essentialist assertions, and another community that makes Lewis's four-dimensionalist (...) assertions, the members of each community speak the truth in their respective languages. This follows from an application of the principle of interpretive charity to the two communities. (shrink)

When is there no fact of the matter about a metaphysical question? When multiple candidate meanings are equally eligible, in David Lewis's sense, and fit equally well with ordinary usage. Thus given certain ontological schemes, there is no fact of the matter whether the criterion of personal identity over time is physical or psychological. But given other ontological schemes there is a fact of the matter; and there is a fact of the matter about which ontological scheme is correct.

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. (shrink)

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. (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.

An introduction to temporal parts theory. Most of us believe in spatial parts: hands are spatial parts of people, an electron is a spatial part of a hydrogen atom, the earth is a spatial part of the solar system. Why are these parts "spatial" parts? Because they are spatially smaller: the hand is spatially smaller than the person, the electron is spatially smaller than the atom, the earth is spatially smaller than the solar system. Temporal parts, then, are parts that (...) are temporally smaller. My current temporal part, "me-today", we might call it, is temporally smaller than me, since it exists today and only today. Temporal parts theory says that objects are made up of temporal as well as spatial parts. (shrink)

SummaryI discuss a simple case in which theories with different ontologies appear equally adequate in every way. . I contend that the appearance of equal adequacy is correct, and that what this shows is that the notion of “existence” has a variety of different but legitimate uses. I also argue that this provides a counterexample to the claim advanced by Davidson, that conceptual relativity is incoherent.RésuméJe discute un cas simple où des théories comportant des ontologies différentes apparaissent également adéquates à (...) tout point de vue. . Je prétends que ľapparence ?on;égale adéquation est correcte et ceci montre que la notion ?on;existence a plusieurs sens différents, mais également légitimes. Je montre aussi que cela constitue un contre‐exemple à la thèse avancée par Davidson, selon laquelle la relativité con‐ceptuelle est incoherénte.ZusammenfassungIch diskutiere einen einfachen Fall, wo Theorien mit verschiedenen Ontologien in jeder Beziehung als gleich adäquat erscheinen. . Ich behaupte, dass die Ansicht, wonach gleiche Adäquatheit bestehen soil, korrekt ist und dass entsprechend der Begriff der Existenz mehrere verschiedene Verwendungs‐weisen hat, die alle legitim sind. Ich argumentiere, dass damit ein Gegenbeispiel zu Davidsons Auffassung vorliegt, wonach die These der begrifflichen Relativität inkohärent sein soil. (shrink)

In (2001), (2003), and elsewhere, Ted Sider presents two arguments concerning the existential quantifier which are justly central to the recent discussion of metaontology. What we will call Sider's indeterminacy argument is an attempted reductio of the suggestion that the existential quantifier might be semantically indeterminate. What we will call Sider's naturalness argument is an argument for the claim that the semantic value of the existential quantifier is the most eligible existence-like meaning there is, à la David Lewis' eligibility theory (...) of meaning. We will argue that these arguments cannot be jointly maintained: Sider must give up at least one. Before arguing this, we will present Sider's two arguments in a bit more detail, and discuss their relationship. A few remarks on the broader significance of our conclusions are in order at the outset. One may think that since one successful argument for a given conclusion is sufficient the point that Sider's arguments cannot both work is purely academic. But we think that Sider's two arguments at bottom reflect different ways of thinking about metaphysics. Moreover, we think that it is only the naturalness argument that promises to deliver all that Sider wants when it comes to metaontology, and it is only the indeterminacy argument that promises to deliver all that Sider wants when it comes to ontology. (shrink)