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)

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)

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)

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)

Are we the people we were? If we are continuants, then the answer to this question is an affirmative one. But it is a moot point whether anything is a continuant. The debate over this issue—of whether there are such things as continuants—is often conducted in the context of theories concerning the apparent passage of time. Thus it has been argued that the tenseless theory of time, according to which time does not really pass, forces us to tear down part (...) of the basis for the intuitive distinction between ordinary, reidentifiable objects on the one hand, and processes on the other, and to regard such objects as mountains as persisting through time in exactly the way that thunderstorms do: by having distinct temporal parts at different times. I confess that I am a tenseless theorist of time, and take that theory to entail such a conclusion about the persistence of objects. But it is not just a certain stance over time’s passage that motivates sympathy towards temporal parts and suspicion of continuants. Thinking of objects as having temporal parts sits more comfortably than does the rival view with two natural assumptions concerning continuity: that beginning and ceasing to exist, at least for most objects, involves underlying changes which are continuous in nature; and that objects exhibit continuity through time, in the sense of not having gaps in their existence. Or so I shall argue in what follows. (shrink)

I argue that two competing accounts of persistence, three and four dimensionalism, are in fact metaphysically equivalent. I begin by clearly defining three and four dimensionalism, and then I show that the two theories are intertranslatable and equally simple. Through consideration of a number of different cases where intuitions about persistence are contradictory, I then go on to show that both theories describe these cases in the same manner. Further consideration of some empirical issues arising from the theory of special (...) relativity lead me to conclude that the two theories are equally explanatory, and thus finally that they are metaphysically equivalent. (shrink)

In this paper I develop a version of universalism that is non-mereological. Broadly speaking, non-mereological universalism is the thesis that for any arbitrary set of objects and times, there is a persisting object which, at each of those times, will be constituted by those of the objects that exist at that time. I consider two general versions of non-mereological universalism, one which takes basic simples to be enduring objects, and the other which takes simples to be instantaneous objects. This yields (...) three versions of endurantism, of which I ultimately defend the version I call universalist endurantism. Universalist endurantism is the thesis that (i) for any arbitrary set S of instantaneous simples that exist at the same instant, there exists a fusion of the members of S, and (ii) for any arbitrary set S* of instantaneous fusions each of which exist at a different instant, there exists an enduring object O that is constituted by those fusions at those instants. Universalist endurantism is ‘non-mereological’ in that the relation that holds between instantaneous fusions and persisting objects is not the part/whole relation, but rather, is the relation of constitution, thus allowing that the persisting objects are three rather than four dimensional. I argue that universalist endurantism not only has the various benefits of mereological universalism in allowing vagueness to be explicated as semantic indeterminacy, but in addition allows the endurantist to hold that some properties are genuinely intrinsic and are exemplified simpliciter. (shrink)

In this paper I develop a version of universalism that is non-mereological. Broadly speaking, non-mereological universalism is the thesis that for any arbitrary set of objects and times, there is a persisting object which, at each of those times, will be constituted by those of the objects that exist at that time. I consider two general versions of non-mereological universalism, one which takes basic simples to be enduring objects, and the other which takes simples to be instantaneous objects. This yields (...) three versions of endurantism, of which I ultimately defend the version I call universalist endurantism. Universalist endurantism is the thesis that for any arbitrary set S of instantaneous simples that exist at the same instant, there exists a fusion of the members of S, and for any arbitrary set S* of instantaneous fusions each of which exist at a different instant, there exists an enduring object O that is constituted by those fusions at those instants. Universalist endurantism is ‘non-mereological’ in that the relation that holds between instantaneous fusions and persisting objects is not the part/whole relation, but rather, is the relation of constitution, thus allowing that the persisting objects are three rather than four dimensional. I argue that universalist endurantism not only has the various benefits of mereological universalism in allowing vagueness to be explicated as semantic indeterminacy, but in addition allows the endurantist to hold that some properties are genuinely intrinsic and are exemplified simpliciter. (shrink)

There is a general form of an argument which I call the ‘argument from vagueness’ which attempts to show that objects persist by perduring, via the claim that vagueness is never ontological in nature and thus that composition is unrestricted. I argue that even if we grant that vagueness is always the result of semantic indeterminacy rather than ontological vagueness, and thus also grant that composition is unrestricted, it does not follow that objects persist by perduring. Unrestricted mereological composition lacks (...) the power to ensure that there exist instantaneous objects that wholly overlap persisting objects at times, and thus lacks the power to ensure that there exists anything that could be called a temporal part. Even if we grant that such instantaneous objects exist, however, I argue that it does not follow that objects perdure. To show this I briefly outline a coherent version of three dimensionalism that grants just such an assumption. Thus considerations pertaining to the nature of vagueness need not lead us inevitably to accept perdurantism. (shrink)

The thesis of 3D/4D equivalence states that every three-dimensional description of the world is translatable without remainder into a four-dimensional description, and vice versa. In representing an object in 3D or in 4D terms we are giving alternative descriptions of one and the same thing, and debates over whether the ontology of the physical world is "really" 3D or 4D are pointless. The twins paradox is shown to rest, in relativistic 4D geometry, on a reversed law of triangle inequality. But (...) considering the twins as 3D beings who age through time, the paradox implies that time passes at different rates in different reference frames, and therefore that the concept of a single global or Absolute time is unsustainable. (shrink)

Are we the people we were? If we are continuants, then the answer to this question is an affirmative one. But it is a moot point whether anything is a continuant. The debate over this issue—of whether there are such things as continuants—is often conducted in the context of theories concerning the apparent passage of time. Thus it has been argued that the tenseless theory of time, according to which time does not really pass, forces us to tear down part (...) of the basis for the intuitive distinction between ordinary, reidentifiable objects on the one hand, and processes on the other, and to regard such objects as mountains as persisting through time in exactly the way that thunderstorms do: by having distinct temporal parts at different times. I confess that I am a tenseless theorist of time, and take that theory to entail such a conclusion about the persistence of objects. But it is not just a certain stance over time’s passage that motivates sympathy towards temporal parts and suspicion of continuants. Thinking of objects as having temporal parts sits more comfortably than does the rival view with two natural assumptions concerning continuity: that beginning and ceasing to exist, at least for most objects, involves underlying changes which are continuous in nature; and that objects exhibit continuity through time, in the sense of not having gaps in their existence. Or so I shall argue in what follows. (shrink)

In his excellent book, Four-Dimensionalism: An Ontology of Persistence and Time (Sider, 2001), Theodore Sider defends a version of four-dimensionalism which he calls the ‘stage-theory’. This paper focuses on Sider's argument from vagueness and argues that, due to the problematic nature of the argument from vagueness, Sider’s case in favor of four-dimensionalism is in the end not successful.

Whenever an object constitutes, makes up or composes another object, the objects in question share a striking number of properties. This paper is addressed to the question of what might account for the intimate relation and striking similarity between constitutionally related objects. According to my account, the similarities between constitutionally related objects are captured at least in part by means of a principle akin to that of strong supervenience. My paper addresses two main issues. First, I propose independently plausible principles (...) by means of which to delineate, in a non-ad-hoc, non-stipulative and non-circular fashion, those properties which can be expected to be shared among constitutionally related objects in virtue of their being so related from those which in general cannot be expected to be shared, or which are shared for other reasons. Secondly,I spell out in detail the nature of the supervenience-principle at work in this context. My account thus aims at isolating, in a methodologically responsible fashion, the particular sort of restricted indiscernibility principle which is a component of the constitution-relation. (shrink)

Sider has argued that four‐dimensionalism can be given a clear and coherent formulation, and has attempted to provide one. He has also argued that three‐dimensionalism resists adequate formulation. I argue that Sider's worries about whether there is an adequate formulation of three‐dimensionalism are misplaced, and suggest a formulation of three‐dimensionalism different from the ones considered and rejected by Sider. I then give a ‘matching’ formulation of four‐dimensionalism, and argue that it captures four‐dimensionalism better than Sider's own formulation of that doctrine.

E. J. Lowe; The problem of the many and the vagueness of constitution, Analysis, Volume 55, Issue 3, 1 July 1995, Pages 179–182, https://doi.org/10.1093/analys/.

Occasions of Identity is an exploration of timeless philosophical issues about persistence, change, time, and sameness. Andre Gallois offers a critical survey of various rival views about the nature of identity and change, and puts forward his own original theory. He supports the idea of occasional identities, arguing that it is coherent and helpful to suppose that things can be identical at one time but distinct at another. Gallois defends this view, demonstrating how it can solve puzzles about persistence dating (...) back to the Ancient Greeks, and investigates the metaphysical consequences of rejecting the necessity and eternity of identities. (shrink)