This is the text of The Lindley Lecture for 1962, given by Arthur N. Prior (1914-1969).

Four- Dimensionalism defends the thesis that the material world is composed of temporal as well as spatial parts. This defense includes a novel account of persistence over time, new arguments in favour of the four-dimensional ontology, and responses to the challenges four- dimensionalism faces." "Theodore Sider pays particular attention to the philosophy of time, including a strong series of arguments against presentism, the thesis that only the present is real. Arguments offered in favour of four- dimensionalism include novel arguments based (...) on time travel, the debate between spacetime substantivalists and relationalists, and vagueness. Also included is a comprehensive discussion of the paradoxes of coinciding material objects, and a novel resolution of those paradoxes based on temporal counterpart theory. In conclusion Sider replies to prominent objections to four- dimensionalism, including discussion of the problem of the rotating homogenous disk. (shrink)

I offer an interpretation and a partial defense of Kit Fine's ‘Argument from Passage’, which is situated within his reconstruction of McTaggart's paradox. Fine argues that existing A-theoretic approaches to passage are no more dynamic, i.e. capture passage no better, than the B-theory. I argue that this comparative claim is correct. Our intuitive picture of passage, which inclines us towards A-theories, suggests more than coherent A-theories can deliver. In Finean terms, the picture requires not only Realism about tensed facts, but (...) also Neutrality, i.e. the tensed facts not being ‘oriented towards’ one privileged time. However unlike Fine, and unlike others who advance McTaggartian arguments, I take McTaggart's paradox to indicate neither the need for a more dynamic theory of passage nor that time does not pass. A more dynamic theory is not to be had: Fine's ‘non-standard realism’ amounts to no more than a conceptual gesture. But instead of concluding that time does not pass, we should conclude that theories of passage cannot deliver the dynamicity of our intuitive picture. For this reason, a B-theoretic account of passage that simply identifies passage with the succession of times is a serious contender. (shrink)

Cappelen and Hawthorne present a powerful critique of fashionable relativist accounts of truth, and the foundational ideas in semantics on which the new relativism draws. They argue compellingly that the contents of thought and talk are propositions that instantiate the fundamental monadic properties of truth and falsity.

The beginning of the twenty-first century saw something of a comeback for relativism within analytical philosophy. Relativism and Monadic Truth has three main goals. First, we wished to clarify what we take to be the key moving parts in the intellectual machinations of self-described relativists. Secondly, we aimed to expose fundamental flaws in those argumentative strategies that drive the pro-relativist movement and precursors from which they draw inspiration. Thirdly, we hoped that our polemic would serve as an indirect defence of (...) a traditional and natural picture concerning truth. According to this picture, what we call ‘Simplicity’, the fundamental structure of semantic reality is best revealed by construing truth as a simple monadic property of propositions that serve as the objects of belief, assertion, meaning and agreement. Our project was not a straightforward one. So-called relativists are not uniform in their key ideology, are often sloppy, casual, obscure or confused in their self-characterization, and differ in their argumentative emphasis among themselves and over time, thereby presenting a target that is both amorphous and shifty. This is an area where parties will frequently claim not to understand each other and where certain parties will sometimes accuse others of failing to make any sense at all. In such a situation, any effort to impose order will inevitably strike some parties as tendentious and unfair. That said, we felt that we had enough of …. (shrink)

Cappelen and Hawthorne present a powerful critique of fashionable relativist accounts of truth, and the foundational ideas in semantics on which the new relativism draws. They argue compellingly that the contents of thought and talk are propositions that instantiate the fundamental monadic properties of truth and falsity.

First published in 2000. Routledge is an imprint of Taylor & Francis, an informa company.

Tensism holds that the present moment has a special status that sets it apart from the past and the future, independently of perceivers. One of the main objections to this view has been Einstein’s argument from special relativity, which aims at showing that absolute simultaneity is a myth. We argue that the moving observer in a causal variant of Einstein’s original thought experiment is subject to a temporal illusion. Owing to the analogy of the cases, this casts doubt on the (...) conjectures that there is no privileged frame of reference and that special relativity poses a problem for tensism. (shrink)

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.

∗ Apologies to Mark Hinchliff for stealing the title of his dissertation. (See Hinchliff, A Defense of Presentism. As it turns out, however, the version of Presentism defended here is different from the version defended by Hinchliff. See Section 3.1 below.).

It seems obvious that I could have failed to exist. My parents could easily never have met, in which case I should never have been conceived and born. The like applies to everyone. More generally, it seems plausible that whatever exists in space and time could have failed to exist. Events could have taken an utterly different course. Our existence, like most other aspects of our lives, appears frighteningly contingent. It is therefore surprising that there is a proof of my (...) necessary existence, a proof that generalizes to everything whatsoever. I will explain the proof and discuss what to make of it. A first reaction is that a ‘proof’ of such an outrageous conclusion must contain some dreadful fallacy. Yet the proof does not collapse under scrutiny. Further reflection suggests that, suitably interpreted, it may be sound. So interpreted, the conclusion is not outrageous, although it may not be the view you first thought of. (shrink)

Timothy Williamson thinks that every object is a necessary, eternal existent. In defense of his view, Williamson appeals primarily to considerations from modal and tense logic. While I am uncertain about his modal claims, I think there are good metaphysical reasons to believe permanentism: the principle that everything always exists. B-theorists of time and change have long denied that objects change with respect to unqualified existence. But aside from Williamson, nearly all A-theorists defend temporaryism: the principle that there are temporary (...) existents. I think A-theorists are better off without this added commitment, but I will not argue for that in any great detail here. Instead, I will contend that a very tempting A-theoretic argument for temporaryism is unsound. In the first half of the paper, I will develop the Moorean “common sense” argument for temporaryism and dispute its central premise, namely that temporaryism is a valid generalization from highly plausible beliefs about change. I will argue that given the pervasive vagueness in our ordinary beliefs about change and the background commitments of all A-theories, no party can claim to be the common sense view because no party can accommodate most of our common sense beliefs about change in existence. In the second half of the paper, I will propose a permanentist A-theory that explains all change over time as a species of property change. I call it the minimal A-theory, since it dispenses with the change in existence assumption. As we'll see, the permanentist alternative performs well enough in explaining our ordinary beliefs about change, and it has better prospects for answering some objections commonly levied against A-theories. (shrink)

This paper presents a new argument against A-theories of time. A-theorists hold that there is an objective now (present moment) and an objective flow of time, the latter constituted by the movement of the objective now through time. A-theorists therefore want to draw different pictures of reality—showing the objective now in different positions—depending upon the time at which the picture is drawn. In this paper it is argued that the times at which the different pictures are drawn may be taken (...) to be normal times or hypertimes. If they are normal times then the A-theory is inconsistent, or else collapses to the B-theory—and appealing to primitive tense operators will not help A-theorists avoid this conclusion. If the times are hypertimes then the A-theory is consistent, but deeply problematic none the less. (shrink)

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

The debate between A-theory and B-theory in the philosophy of time is a persistent one. It is not always clear, however, what the terms of this debate are. A-theorists are often lumped with a miscellaneous collection of heterodox doctrines: the view that only the present exists, that time flows relentlessly, or that presentness is a property (Williams 1996); that time passes, tense is unanalysable, or that earlier than and later than are defined in terms of pastness, presentness, and futurity (Bigelow (...) 1991); or that events or facts (as opposed to language) are “tensed” (Mellor 1993). B-theorists then argue that the A-theory is incoherent, using variants on J.M.E. McTaggart’s argument for the unreality of time (McTaggart 1927, ch. 33). (shrink)

In "How Do We Know It Is Now Now?" David Braddon-Mitchell (Analysis 2004) develops an objection to the thesis that the past is real but the future is not. He notes my response to this, namely that the past, although real, is lifeless and (a fortiori?) lacking in sentience. He argues, however, that this response, which I call 'the past is dead hypothesis', is not tenable if combined with 'special relativity'. My purpose in this reply is to argue that, on (...) the contrary, 'special relativity' supports the thesis that the future is unreal. (shrink)

How can we talk meaningfully about the past if it does not exist to be talked about? What gives time its direction? Is time travel possible? This defence of presentism - the view that only the present exists - makes an original contribution to a fast growing and exciting debate.

Timothy Williamson gives an original and provocative treatment of deep metaphysical questions about existence, contingency, and change, using the latest resources of quantified modal logic. Contrary to the widespread assumption that logic and metaphysics are disjoint, he argues that modal logic provides a structural core for metaphysics.

In order to perfectly describe the world, it is not enough to speak truly. One must also use the right concepts - including the right logical concepts. One must use concepts that "carve at the joints", that give the world's "structure". There is an objectively correct way to "write the book of the world". Much of metaphysics, as traditionally conceived, is about the fundamental nature of reality; in the present terms, this is about the world's structure. Metametaphysics - inquiry into (...) the status of metaphysical questions - turns on structure. The question of whether ontological, causal, or modal questions are "substantive" is in large part a question of whether the world has ontological, causal, and modal structure - whether quantifiers, causal relations, and modal operators carve at the joints. (shrink)

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-".

Michael Tooley presents a major new philosophical theory of the nature of time, offering a powerful alternative to the traditional "tensed" and recent "tenseless" accounts of time. He argues for a dynamic conception of the universe, in which past, present, and future are not merely subjective features of experience. He claims that the past and the present are real, while the future is not. Tooley's approach accounts for time in terms of causation. He therefore claims that the key to understanding (...) the dynamic nature of the universe is to understand the nature of causation. Time, Tense, and Causation is a landmark treatment of one of the oldest and most perplexing intellectual problems, and will be fascinating reading for anyone interested in the character of time. (shrink)

How can we talk meaningfully about the past if it does not exist to be talked about? What gives time its direction? Is time travel possible? This defence of presentism - the view that only the present exists - makes an original contribution to a fast growing and exciting debate.

Uncorrected Proof; please cite published version.

Arguments about temporal becoming often get nowhere. One reason for the impasse lies in the fact that the issue has been formulated as a choice between science on the one hand and common sense (or ordinary language) on the other as the primary source of ontological commitment.' Often' proponents of attributing temporal becoming to the physical universe look to everyday temporal concepts, find them infested with notions involving temporal becoming and conclude that becoming is a basic feature of the physical (...) world. Their opponents may look to physical science, find no reference to temporal becoming and conclude that becoming is not part of the extramental universe.2 Thus construed, the issue of temporal becoming is not directly amenable to argument. This stalemate will be broken, however, if I accomplish my aim: to (re)formulate the question of temporal becoming so that it is subject to adjudication; to show how objections to the thesis of the mind-dependence of becoming can fruitfully be seen (and in a sense unified) as attacks on a single argument for the thesis, an argument from physics; and to defend the con'elusion of the argument from physics from heretofore unanswered objections. The question of the status of temporal becoming is the question of the status of past, present and future.' Events which are at one time in the future, are said to become present and subsequently to recede into the past. Since past and future can be defined as 'earlier than now' and 'later than.. (shrink)