Hud Hudson has recently suggested a scenario intended to show that, assuming the doctrine of temporal parts and a sufficiently liberal view of composition, there are material objects that move faster than light. I accept Hudson's conditional but contend that his modus ponens is less plausible that the corresponding modus tollens. Reversed in this way, the argument stemming from the scenario raises the cost of mereological liberalism and advances the case for a principled restriction on diachronic composition.

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.

I offer a clear conception of a temporal part that does not make the existence of temporal parts implausible. This can be done if (and only if) we think of physical objects as four dimensional, The fourth dimension being time. Unless we are willing to deny the existence of most spatial parts, Or willing to accept the possibility of coincident entities, Or accept something even more implausible, We should accept the existence of temporal parts.

이 논문은 데이빗 루이스의 시간적 부분 이론(temporal part theory)과 물질적 구성(material consitution)에 대한 반 인와겐의 입장에 대한 논의를 출발점으로 삼는다. 먼저 필자는 루이스의 시간적 부분이론을 반박한다. 루이스의 이론의 핵심적인 내용을 똑같이 반영(mirror)하면서도 그 이론과 상충하는 이론을 구성하고 이 두 이론 중 어느 한 쪽을 선택하는 것은 결국은 임의적인(arbitrary) 결정을 하는 것인데 이 사실은 이 두 이론 모두를 매력적이지 않게 만든다고 주장한다. 이 두 이론을 모두 거부한다면 우리는 사물을 (특별히 문제되는 사물이 ‘자아’라면 더더욱) 어디에 위치시켜야 하는지 새로운 가능성을 탐색해 보게 (...) 된다. 다음으로 이 논문은 떨어지지 않은 임의적인 부분(arbitrary undetached part)에 대한 반 인와 겐의 논증을 살펴보고 그 논증을 준거점으로 삼아 물질적 구성(material consitution)에 대한 여러 논문들에 등장한 이론적 가능성을 일별한다. 필자는 이 여러 입장들 뒤에 근본적인 전제로 기능하고 있는 철학적 원자론(philosophical atomism)과 그 이론이 내포하는 환원주의적 접근이 자아가 존재하고 시간 속에 지속한다(endure through time)는 근본적인 믿음을 포함하는 ‘자아의 선차성’ 논제를 위협한다는 것을 지적하고 루이스의 이론에 대한 논의에서 얻은 결론과 결합하여, 상당히 이상해보이지만 고려해볼만한 이론적 가능성으로 자아가 시간 속에 지속하는 영차원의(zero-dimensional) 존재라는 가능성을 제기한다. (shrink)

In this paper I consider an objection that friends of the Metaphysic of Temporal Parts (MTP) press against other solutions to the problem of temporary intrinsics and turn it against the MTP itself. I do not argue that the MTP must be false, nor do I argue that there are no arguments in favor of the MTP. Rather, the conclusion I draw is conditional: if the MTP provides an adequate response to the problem of temporary intrinsics, then the (...) MTP provides no reason to reject our commonsense view of the nature of material objects. (shrink)

This article discusses recent work in metaphysics on temporal parts. After a short introduction introducing the notion of a temporal part, we examine several well‐known arguments for the view that ordinary material objects such as tables, trees, and persons have temporal parts: (1) positing temporal parts makes it possible to solve puzzles of coincidence (e.g., the statue/lump puzzle); (2) positing temporal parts makes it possible to solve the problem of intrinsic change (...) over time; and (3) the existence of temporal parts can be demonstrated based on considerations about vagueness in composition. We conclude by examining briefly a recent argument that the dispute over whether there are temporal parts is merely verbal. (shrink)

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)

In debate about the nature of persistence over time, the view that material objects endure has played the role of "champion" and the view that they perdure has played the role of the "challenger." It has fallen to the perdurantists rather than the endurantists to motivate their view, to provide reasons for accepting it that override whatever initial presumption there is against it. Perdurantists have sought to discharge their burden in several ways. For example, perdurantism has been recommend on the (...) grounds that: (i) it solves several of the puzzles that raise the problem of material constitution; (ii) it is (at least) suggested by the special theory of relativity (hereafter "SR"); (iii) it is the only view that makes sense out of the possibility of intrinsic change; (iv) it is the only view consistent with the doctrine of Humean supervenience; and (v) it makes better sense than its competitor out of the possibility of fission. There are primary and most powerful claims that have been made on behalf of perdurantism. They are individually persuasive and together they constitute a formidable assault upon the hegemony of endurantism. Endurantists of course, have not been without reply. However, since endurantists typically respond to these claims one at a time and in different ways, it is easy to get the impression that perdurantism offers a single, neat solution to a host of problems whereas endurantism requires a patchwork of different strategies. But this impression is an illusion. In Rea 1995, I argued that though perdurantism does solve some of the puzzles that raise the problem of material constitution, it does not solve the problem of material constitution itself. Thus, the problem of material constitution really has no bearing on the debate between endurantists and perdurantists. In his paper, I will show that the same is true with respect to SR, the problem of intrinsic change, the doctrine of Humean supervenience, and the possibility of fission. In short, I will argue that none of (ii-v) is true and that therefore the doctrine of temporal parts stands unmotivated. (shrink)

What is a temporal part? Most accounts explain it in terms of timeless parthood: a thing's having a part without temporal qualification. Some find this hard to understand, and thus find the view that persisting things have temporal parts--fourdimensionalism--unintelligible. T. Sider offers to help by defining temporal parthood in terms of a thing's having a part at a time. I argue that no such account can capture the notion of a temporal part that figures (...) in orthodox four-dimensionalism: temporal parts must be timeless parts. This enables us to state four-dimensionalism more clearly. (shrink)

Ignoring the temporal dimension, an object such as a railway tunnel or a human body is a three-dimensional whole composed of three-dimensional parts. The four-dimensionalist holds that a physical object exhibiting identity across time—Descartes, for example—is a four-dimensional whole composed of 'briefer' four-dimensional objects, its temporal parts. Peter van Inwagen (1990) has argued that four-dimensionalism cannot be sustained, or at best can be sustained only by a counterpart theorist. We argue that different schemes of individuation of (...) temporal parts are available, which undermines van Inwagen's argument. (shrink)

The standard definition of an instantaneous temporal part cannot properly deal with cases involving time travel. This paper provides a new definition of an instantaneous temporal part by appealing to David Lewis's distinction between external time and personal time. The new definition avoids the problems because it does not allow more than one instantaneous temporal part of an object at each moment of its personal time. We argue that this new definition, combined with our new perdurantist semantic (...) thesis, deals with cases of time travel successfully. (shrink)

In this paper, I try to make a bundle theory of objects consistentwith a temporal parts theory of object persistence. To that end,I propose that such bundles are made up of tropes includingthe co-instantiation relation.

This paper argues that, in light of certain scenarios involving time travel, Sider’s definition of ‘instantaneous temporal part’ cannot be accepted in conjunction with a semantic thesis that perdurantists often assume. I examine a rejoinder from Sider, as well as Thomson’s alternative definition of ‘instantaneous temporal part’, and show how neither helps. Given this, we should give up on the perdurantist semantic thesis. I end by recommending that, once we no longer accept such semantics, we should accept a (...) new set of definitions, which are superior in certain respects to Sider’s original set. (shrink)

To what extent is time similar to space? in this paper it is shown that the claim, Made by richard taylor among others, That time and space are "radically alike" is unfounded. This claim can be supported only by employing the notion of temporal parts. It is shown that if objects are regarded as having temporal parts as well as spatial parts, Then serious disanalogies exist between time and space. Furthermore, If objects are said to (...) have temporal parts, Then it must also be held that time is in a very important sense "prior" to space and this that time and space are not only unlike in certain respects but indeed are radically dissimilar. Moreover, The so-Called "manifold theory of time" necessarily makes use of the notion of temporal parts and therefore should hold that time and space are quite unlike. But since an important part of the manifold theory of time is the claim that time and space are very much alike, This theory is to that extent not satisfactory. (shrink)

In debate about the nature of persistence over time, the view that material objects endure has played the role of “champion” and the view that they perdure has played the role of “challenger.” As in other contests, the champion’s job is merely to defend her title, whereas the challenger’s job is to prove herself worthy. I have no view about how these roles came to be assigned; but the historical fact is that perdurantists have traditionally borne the proverbial burden of (...) proof in this debate. It has fallen to the perdurantists rather than the endurantists to motivate their view, to provide reasons for accepting it that override whatever initial presumption there is against it. (shrink)

The so-called "argument from vagueness", the clearest formulation of which is to be found in Ted Sider’s book Four-dimensionalism, is arguably the most powerful and innovative argument recently offered in support of the view that objects are four-dimensional perdurants. The argument is defective--I submit--and in a number of ways that is worth looking into. But each "defect" corresponds to a model of change that is independently problematic and that can hardly be built into the common-sense picture of the world. So (...) once all the gaps of the argument are filled in, the three-dimensionalist is left with the burden of a response that cannot rely on a passive plea for common sense. The argument is not a threat to common sense as such; it is a threat to the three-dimensionalist faithfulness to common sense. (shrink)

Those who believe that ordinary things have temporal as well as spatial parts must give an account of the truth conditions of temporally modified predications of the form ‘a is F at t ’ in terms of temporal parts. I will argue that the friend of temporal parts is committed to an account of temporal predication that is incompatible with the classical principle of predicate abstraction.

The so-called ‘argument from vagueness’ is among the most powerful and innovative arguments offered in support of the view that objects are four-dimensional perdurants. The argument is defective – I submit – and in a number of ways that are worth looking into. But each ‘defect’, each gap in the argument, corresponds to a model of change that is independently problematic and that can hardly be built into the common-sense picture of the world. So once all the gaps of the (...) argument are filled in, the three-dimensionalist is left with the burden of a response that cannot rely on a passive plea for common sense. The argument is not a threat to common sense as such; it is a threat to the three-dimensionalist faithfulness to common sense. (shrink)

1. Many philosophers think that “What is identity across time?” is an important and meaningful question. I have a great deal of trouble seeing what this question might be. But, very often, if one cannot understand a philosophical question, one’s best course is to look at some alleged answers to it; sometimes these answers enable one to see what question it is that they are offered as answers to. The following passage by Michael Tooley is supposed to provide an answer (...) to the question we are trying to get at. (shrink)

Things change. If anything counts as a datum of metaphysics, that does. Change occurs in many ways: it can be accidental or substantial; essential or non-essential; intrinsic or extrinsic; subjective or objective. Changes can be physical, spatial, quantitative, qualitative, natural, artefactual, conceptual, linguistic. Events are arguably best defined as changes in an object or objects. All change is from something and into something, and hence is at least a two-term relation, involving a term from which and a term to which.

Three Dimensionalists and Four Dimensionalists are engaged in a debate on the topics of persistence and mereology. In this paper, I explore implications of Four Dimensionalism for the formulation of the criterion of personhood and on the question of which individuals satisfy that criterion. In my discussion I argue that the Four Dimensionalist has reason to identify a human person with a proper part of a human organism, and that the Four Dimensionalist has reason to believe that if there is (...) something morally wrong with human abortion or infanticide, it cannot be grounded in claims about the moral status of persons. (shrink)

Things change. If anything counts as a datum of metaphysics, that does. Change occurs in many ways: it can be accidental or substantial; essential or non-essential; intrinsic or extrinsic; subjective or objective. Changes can be physical, spatial, quantitative, qualitative, natural, artefactual, conceptual, linguistic. Events are arguably best defined as changes in an object or objects. All change is from something and into something, and hence is at least a two-term relation, involving a term from which and a term to which.

Naive mereology studies ordinary conceptions of part and whole. Parts, unlike portions, have objective boundaries and many things, such as dances and sermons have temporal parts. In order to deal with Mark Heller's claim that temporal parts "are ontologically no more or less basic than the wholes that they compose," we retell the story of Laplace's Genius, here named "Swifty." Although Swifty processes lots of information very quickly, his conceptual repertoire need not extend beyond fundamental (...) physics. So we attempt to follow Swifty's progress in the acquisition of ordinary concepts such as 'table'. (Puzzles of precision and intrusion appear along the way.) Swifty has to understand what tables are before understanding what temporal portions of tables are. This is one reason for regarding tables as ontologically prior to table portions. intrusion appear along the way.). (shrink)

When we think about ethics, we normally focus on a particular sort of agent: the individual person. Some philosophers have argued that we should rethink the limits of what counts as an ethically relevant unit of agency by expanding outward, and claiming that groups of people can have normative reasons for action. In this paper, I explore whether we can go in the other direction. Are there sub‐personal beings who count as agents with their own reasons for action? In particular, (...) might the temporal parts of persons, beings like “me‐in‐my‐twenties,” be thought of as normative agents? This idea, I argue, has deep attractions, and deep, but surmountable, challenges. And if we do accept this idea, I argue, this can indirectly help to support the case for thinking that groups can have reasons for action. (shrink)

Adopting temporal parts theory is the most popular way of addressing a host of puzzles about diachronic identity. For example, it is not obvious how I am the same person as the baby who shared my name. With the theory, sameness of person, e.g., consists in being comprised by the same temporally extended, four-dimensional object. However, temporal parts theory has unacceptable consequences for notions of freedom and probability. I show that the only acceptable reading of four-dimensionalism (...) entails that the four dimensional object that is me, say, already exists in its entirety. This entails that all of my future properties are already set. This nearly Spinozistic result robs us of familiar notions of choice and possibility. I argue that these notions are more central to our thinking than temporal parts theory, and that on these grounds we must look elsewhere for solutions to our questions about identity across time. (shrink)

A brief introductory note to the Monist issue on "Temporal Parts", setting the background for the eight papers included in the rest of the issue (by Y. Balashov, B. Brogaard, K. Fine, M. Heller, R. LePoidevin, J. Parsons, P. M. Simons, and P. van Inwagen).

This article provides a new context for an established metaphysical debate regarding the problem of persistence. I contend that perdurance, a popular view about persistence which maintains that objects persist by having temporal parts, can be formulated in quantum mechanics due to the existence of a formal analogy between temporal and spatial location. However, this analogy fails due to a ‘no-go’ result which demonstrates that quantum systems cannot be said to have temporal parts in the (...) same way that they have spatial parts. Therefore, if quantum mechanics describes persisting physical objects then those objects cannot be said to perdure. (shrink)

If ordinary objects have temporal parts, then temporal predications have the following truth conditions: necessarily, ( a is F) at t iff a has a temporal part that is located at t and that is F. If ordinary objects have temporal counterparts, then, necessarily, ( a is F) at t iff a has a temporal counterpart that is located at t and that is F. The temporal-parts account allows temporal predication to (...) be closed under the parthood relation: since all that is required to be F at t is to have a temporal part, a t , that is located at t and that is F, every object that has a t as a temporal part is F at t . Similarly for the temporal-counterparts account. Both closure under parthood and closure under counterparthood are shown to have unacceptable consequences. Then strategies for avoiding closure are considered and rejected. (shrink)

The Doctrine of Temporal Parts (sometimes abbreviated herein as 'DTP') asserts that, for each portion (including infinitely small portions) of the smallest period of time during which a material object exists, there is an object-a temporal part of the material object in question-which exists at that and at no other time. In "Things Change," Mark Heller offers an argument for DTP, and responds to a objection, the "No-Change" objection, to that doctrine.2 My goal in this paper is (...) to undermine both Heller's argument in favor of DTP and his response to that criticism. (shrink)

This paper presents the strongest version of a non-perdurantist four-dimensionalism: a theory according to which persisting objects are four-dimensionally extended in space-time, but not in virtue of having maximal temporal parts. The aims of considering such a view are twofold. First, to evaluate whether such an account could provide a plausible middle ground between the two main competitor accounts of persistence: three-dimensionalism and perdurantist four-dimensionalism. Second, to see what light such a theory sheds on the debate between these (...) two competitor theories. I conclude that despite prima facie reasons to suppose that non-perdurantist four-dimensionalism might be a credible alternative to either other account of persistence, ultimately the view is unsuccessful. The reasons for its failure illuminate the sometimes stagnant debate between three-dimensionalists and perdurantists, providing new reasons to prefer a perdurantist metaphysics. (shrink)

In two earlier works (Balashov, 2000a: Philosophical Studies 99, 129–166; 2000b: Philosophy of Science 67 (Suppl), S549–S562), I have argued that considerations based on special relativity and the notion of coexistence favor the perdurance view of persistence over its endurance rival. Cody Gilmore (2002: Philosophical Studies 109, 241–263) has subjected my argument to an insightful three fold critique. In the first part of this paper I respond briefly to Gilmore’s first two objections. I then grant his observation that anyone who (...) can resist the first objection is liable to succumb to the third one. This, however, opens a way to other closely related relativistic arguments against endurantism that are immune to all three objections and, in addition, throw new light on a number of important issues in the ontology of persistence. I develop two such novel arguments in the second half of the paper. (shrink)

The Doctrine of Temporal Parts (sometimes abbreviated herein as 'DTP') asserts that, for each portion (including infinitely small portions) of the smallest period of time during which a material object exists, there is an object-a temporal part of the material object in question-which exists at that and at no other time. In "Things Change," Mark Heller offers an argument for DTP, and responds to a objection, the "No-Change" objection, to that doctrine.2 My goal in this paper is (...) to undermine both Heller's argument in favor of DTP and his response to that criticism. (shrink)

The following quotation, from Frank Jackson, is the beginning of a typical exposition of the debate between those metaphysicians who believe in temporal parts, and those who do not: The dispute between three-dimensionalism and four-dimensionalism, or more precisely, that part of the dispute we will be concerned with, concerns what persistence, and correllatively, what change, comes to. Three-dimensionalism holds that an object exists at a time by being wholly present at that time, and, accordingly, that it persists if (...) it is wholly present at more than one time. For short, it persists by enduring. Four-dimensionalism holds that an object exists at a time by having a temporal part at that time, and it persists if it has distinct temporal parts at more than one time. For short, it persists by perduring. In the light of these comments, some readers will perhaps find the question that forms the title of this paper a little puzzling. They may have learned to use the terms ‘fourdimensionalism’ ‘perdurantism’ and ‘belief in temporal parts’ interchangeably; or perhaps even to define one in terms of the other. Such a usage, however, is inapposite. We might imagine a Flatland-like world of two spatial dimensions and one temporal, whose philosophers are divided between a theory of persistence on which they persist by having temporal parts, and a theory on which they persist by being wholly located in each of several times. This is just the same issue we face, but at least the label ‘four-dimensionalism’ seems inapposite: the four-dimensionalist Flatlanders believe in only three dimensions! (shrink)

This chapter discusses the “real distinction” between the mind and the body and a demonstration of the immortality of the soul as demonstrated in Descartes’s Meditations. Early readers of Descartes’s work like Arnauld and Mersenne rejected the idea on the grounds that “it does not seem to follow from the fact that the mind is distinct from the body that it is incorruptible or immortal.” In light of this, Descartes devised a more detailed proof of immortality based on two assumptions (...) not made explicit in the six meditations. These two assumptions are discussed in this chapter, together with the difficulties that arise by making them. Descartes’s arguments are also examined vis-à-vis the metaphysical distinction between endurance and perdurance. (shrink)

This paper presents the strongest version of a non-perdurantist four-dimensionalism: a theory according to which persisting objects are four-dimensionally extended in space-time, but not in virtue of having maximal temporal parts. The aims of considering such a view are twofold. First, to evaluate whether such an account could provide a plausible middle ground between the two main competitor accounts of persistence: three-dimensionalism and perdurantist four-dimensionalism. Second, to see what light such a theory sheds on the debate between these (...) two competitor theories. I conclude that despite prima facie reasons to suppose that non-perdurantist four-dimensionalism might be a credible alternative to either other account of persistence, ultimately the view is unsuccessful. The reasons for its failure illuminate the sometimes stagnant debate between three-dimensionalists and perdurantists, providing new reasons to prefer a perdurantist metaphysics. (shrink)

Sider (2001) and Hawley (2001) argue that, in order to account for the mere possibility of change, temporal parts must be as fine-grained as possible change, and hence as fine-grained as time. However, when dealing with metaphysical possibility, the fine-grainedness of actual time and the fine-grainedness of possible change can come apart. Once this is taken into account, we see that, on certain assumptions about the actual microstructure of time, the modal arguments of Sider and Hawley lead to (...) the problematic claim that temporal parts are more fine-grained than time. The utility of a temporal parts theory thus seems to be sensitive to metaphysically contingent facts concerning the microstructure of time. (shrink)