Stage Theory

Time and modality show remarkable similarities. Each of the most discussed theories in philosophy of time finds an analogous counterpart in modal metaphysics, suggesting that the parallel between the two notions is metaphysically deep. This chapter offers a brief overview of their analogies. Section 1 addresses the analogy between presentism and actualism. Section 2 explores the analogy between non-presentist theories and possibilism. Section 3 discusses the analogy between temporal and modal persistence.

To solve the ship of Theseus puzzle, you need several keys. First of all, we need to fix the application condition of the physical object—it is a vehicle or an object memory; then the identification criterion—the ship was named The Ship of Theseus when he boarded it; and finally the re-application criterion—a ship (or an object memory) when it is the same ship (or object memory) as before. The degree of change from the previous and reference states must be given. (...) The identity of physical objects over time can be expressed by the uniformity of the time slices of the persisting objects. Uniformity exists from the point of view that these instances are temporal cross-sections of the same object; they may differ in other characteristics; there are no general a priori principles independent of practice. The definition of identity is decided by the community of language users. The two states of an object are the same as long as the rate of change of state remains below the threshold value relative to the reference. The two states of an object are similar as long as the change is below a threshold value with respect to each other. Similarity can be described by a tolerance relationship. The mathematical relation describing uniformity is formally an equivalence relation, just as the relation describing identity is an equivalence relation. A physical object is identical to an equivalence class when we speak of the object's identity over time and identical or not identical to an element of the equivalence class when we speak of the object having changed or ceased to exist. (shrink)

Persistence realism is the view that ordinary sentences that we think and utter about persisting objects are often true. Persistence realism involves both a semantic claim, about what it would take for those sentences to be true, and an ontological claim about the way things are. According to persistence realism, given what it would take for persistence sentences to be true, and given the ontology of our world, often such sentences are true. According to persistence error-theory, they are not. This (...) Element considers several different views about the conditions under which those sentences are true. It argues for a view on which it is relatively easy to vindicate persistence realism, because all it takes is for the world to be the way it seems to us. Thereby it argues for the view that relations of numerical identity, or of being-part-of-the-same-object, are neither necessary nor sufficient for persistence realism. (shrink)

Four-dimensionalists think that we persist over time by having different temporal parts at each of the times at which we exist. Eternalists think that all times are equally real. Deprivationists think that death is an evil for the one who dies because it deprives them of something. I argue that four-dimensionalist eternalism, conjoined with a standard deprivationist account of the evil of death, has surprising implications for what we should think about the evil of death. In particular, given these assumptions, (...) we will lack any grounds for thinking that death is an evil for some individuals for whom we would antecedently expect it to be an evil, namely those individuals who cease to exist at death. Alternatively, we will only have some grounds for thinking that death is an evil for certain individuals for whom we might antecedently be more inclined to think death is not an evil, namely those individuals who survive death, in the sense that they continue to exist after death. (shrink)

The debate over persistence currently involves three competing theories—one three-dimensionalist theory called “endurantism” and two four-dimensionalist theories called “perdurantism” and “exdurantism.” This inner debate between the latter two persistence theories is what I aim to clarify, and ultimately, I argue that perdurantism is superior to exdurantism because exdurantism is too extravagant in counting ordinary objects in the world. Extravagant for the reason that objects in their entirety are bound to their momentary stages, and there is practically an interminable number of (...) these stages, which is not reasonable when counting in the ordinary world. (shrink)

What does it mean for an object to persist through time? Consider the statement, ‘My car is filthy, I need to wash it.’ Consider the response, ‘How did it get that way?’ The answer is that dirt, dust and other particles have collected on the car’s surface thus making it filthy. Its properties have changed. At one point in the car’s career, none of that dirt and grime existed on its surface and the car was said to be clean. The (...) fact is that for a car to get dirty, the extension of time is necessary. The standard view of identity is that each thing is entirely itself at any given time. So how can an object remain identical with itself over time, if it changes its properties? In many ways I have different properties now than those I had last week. But if I am different, how then can I be the same? The objective of this article is to answer the question of what it means to say that we and other things persist through time. First I’ll lay out two popular philosophical views of persistence through time, then I will present possible problems with both views. After that, I will outline another possible answer that lies outside of these views. Finally, I will providemy own answer. (shrink)

Pixelism is the combination of three metaphysical thesis, namely a radical form of exdurantism, mereological nihilism and counterpart theory. Pixelism is a theory that evaluates all the metaphysical phenomena of persistence, composition and modality in a homogeneous and consistent manner. In a pixel world, there is no identity over time and over possible worlds and nothing persists over more than an instant or a world. Entities can be univocally identified by a five-coordinates system (the three spatial dimensions, the temporal one (...) and the possible worlds), and their relation is a counterpart relation both in different worlds and at different times or different regions of space. In this paper I will provide two models for pixelism: the first one takes pixels to be hypercubes, i. e. four-dimensional cubes, the acceptance of which is conditional on the acceptance of extended simples. The second one considers pixels as points in a four-dimensional space. (shrink)

How do groups of people persist through time? Groups can change their members, locations, and structure. In this paper, I present puzzles of persistence applied to social groups. I first argue that four-dimensional theories better explain the context sensitivity of how groups persist. I then exploit two unique features of the social to argue for the stage theory of group persistence in particular. First, fusion and fission cases actually happen to social groups, and so cannot be marginalized as “pathological.” Second, (...) it is implausible that groups spatially coincide pre-fission. This means that theories that depend on pre-fission spatial coincidence, such as some endurance theories and the worm theory, cannot explain fission cases. All things considered, the stage theory offers the best explanation of how groups persist. (shrink)

Perdurantists think of continuants as mereological sums of stages from different times. This view of persistence would force us to drop the idea that there is genuine change in the world. By exploiting a presentist metaphysics, Brogaard proposed a theory, called presentist four-dimensionalism, that aims to reconcile perdurantism with the idea that things undergo real change. However, her proposal commits us to reject the idea that stages must exist in their entirety. Giving up the tenet that all the stages are (...) equally real could be a price that perdurantists are unwilling to pay. I argue that Kit Fine ’s fragmentalism provides us with the tools to combine a presentist metaphysics with a perdurantist theory of persistence without giving up the idea that reality is constituted by more than purely present stages. (shrink)

Mark Johnston has recently argued that four-dimensionalist theories of persistence are incompatible with some of our most basic ethical and prudential principles. I argue that although Johnston’s arguments succeed on a worm-theoretic account of persistence, they fail on a stage-theoretic account. So much the worse, I conclude, for the worm theory.

Gabriele Contessa has recently introduced and defended a view he calls ‘non-eliminative nihilism’. Non-eliminative nihilism is the conjunction of mereological nihilism and non-eliminativism about ordinary objects. Mereological nihilism is the thesis that composite objects do not exist, where something is a composite object just in case it has proper parts. Eliminativism about ordinary objects denies that ordinary objects exist. Eliminativism thus implies, for example, that there are no galaxies, planets, stars, ships, tables, books, organisms, cells, molecules, or atoms. Non-eliminativism is (...) the denial of eliminativism. Thus, NEN is the intriguing thesis that although composite objects do not exist, ordinary objects do. In this essay, I, first, summarize Contessa’s core support for NEN. Second, I describe two flaws in that support when it comes to organismic terms. Third, I consider and reject two possible responses on behalf of NEN’s defenders. Fourth, I show how the flaws cast doubt upon NEN itself. Finally, I offer reasons to think that if nihilism is true, then the folk have probably been trying to fix the reference of organismic terms to apparent objects within illusions. (shrink)

In this article I introduce a hybrid view of persistence whereby simple objects persist by enduring while composite objects persist by being stage-related. I first show how, by sharing certain features and not others with the standard views of persistence, this hybrid view navigates two metaphysical problems that have been raised against such standard views. I then consider some implications of the view by addressing a couple of worries that may be raised against it. I conclude that this hybrid view (...) provides an attractive theory, one that deserves further investigation in the debate on persistence. (shrink)

Derek Parfit’s thesis that identity doesn’t matter in survival has been extensively discussed except for its metaphysical robustness. How can we justify the abandonment of identity in the way Parfit suggests? My argument is the following. Those who want to endorse the thesis that identity doesn’t matter (and, therefore, abandon identity across time) should adopt exdurantism, i.e. a metaphysics according to which the world is composed by temporal parts each existing at a time and according to which there is nothing (...) as a numerically same entity which exists at different times. I show that the metaphysics behind Parfit’s theory is neither compatible with endurantism, according to which object persists by being wholly present at different times, nor with perdurantism, according to which entities are aggregates of temporal and spatial parts. (shrink)

The fact that names refer to individuals is a basic assumption of referentialist theories of proper names, but the notion of individual is systematically taken for granted in those theories. The present paper follows that basic assumption, but proposes to analyze the notion of individual prior to the development of any semantic theory of proper names. It will be argued that a particular perdurantist conception of individual should be adopted, which distinguishes the notions of individual occurrence, and individual simpliciter. A (...) new theory of proper names (called the cluster-occurrence theory) is presented, according to which names refer to individual occurrences, and the intension associated with a name is an individual simpliciter. The merits of the new theory are then assessed in confrontation with its standard rival accounts. (shrink)

Given the assertion of a relation between two types, like: “Epidermis has part some Keratinocyte”, we define silent change as any kind of change of the instance-relata of the relation in question that does not change the truth-value of the respective type-level assertion. Such assertions are notoriously difficult to model in OWL 2. To address this problem, we distinguish different modes of type-level relatedness giving rise to this problem and describe a conservative extension to the BFO top-level ontology that allows (...) expressing these modes. (shrink)

My present inclination is to say that both identity and relational analyses are intelligible hypotheses. I reject the identity analysis, looking rather to relations between different phases to secure the unity of a particular over time. But I do not think that the identity view can be rejected as illogical. If it is to be rejected, then I think it must be rejected for Occamist reasons. The different phases exist, and so do their relations. These phases so related, it seems, (...) are sufficient to secure identity through time for all particulars. I suggest, then, that the identity view of identity through time is not illogical. The question is rather whether it is a postulation which is fruitful, or expedient, or which we are compelled, to make. (Armstrong p. 70, 1980) This paper considers this view, articulated by Armstrong and argues that recent work on persistence sheds light on this issue. (shrink)

In this article, I am interested in four versions of what is often referred to as "the Humphrey objection". This objection was initially raised by Kripke against Lewis's modal counterpart theory, so this is where I will start the discussion. As we will see, there is a perfectly good answer to the objection. I will then examine other places where a similar objection can be raised: it can arise in the case of temporal counterpart theory (in fact, it can arise (...) in the case of all kinds of counterpart theories, independently on modal realism), and a very similar worry can also arise against modal realism itself or against an ersatzist theory of possible worlds itself. For similar reasons, in similar situations, a similar objection will arise. What is interesting is that it is not the case that a similar response can be given in all of these similar cases. So, in the end, we will see what dissimilarities there are and how and why they are relevant. In particular, we will see the differences there are between alethic modalities and temporal modalities. In the case of alethic modalities (metaphysical necessity and possibility), the objection can be answered by appealing to the notion of representation, while this does not work very well in the case of temporal modalities. (shrink)

This chapter explores the connections between David Lewis's perdurance theory and his Humean supervenience, arguing that his influential argument about temporary intrinsics is best seen in this light. It presents domestic dispute within the anti‐endurantist camp and analyzes the following questions: why does Lewis identify ordinary objects with world‐bound parts of transworld objects, but not with time‐bound parts of transtemporal objects? Given that Lewis is a counterpart theorist about modality, why isn't he a stage theorist about persistence? Humean supervenience in (...) isolation does not entail perdurance theory, even for the actual world. Lewis's treatment of temporary intrinsics in On the Plurality of Worlds forms part of a discussion of both persistence and its modal analogue, for which there is no neutral term. Perdurance theory is challenged by the stage theory of persistence, which identifies ordinary objects with brief stages instead of transtemporal sums of those stages. (shrink)

This paper presents an argument that the way we experience time is more consistent with our being instantaneous objects than with our being temporally extended throughout our entire lifetimes. By argument to the best explanation therefore, experiencing subjects persons are stages, rather than worms.

In this paper, I tackle the problem of diachronic identity. Far from providing a criterion for identity over time, the aim of this work is to understand if this issue pertains to ontology, conceived as that part of philosophy that tries to answer the question about what entities exist, or metaphysics, conceived as that part of philosophy that tries to explain, of those entities, what they are. On the face of it, only metaphysics has the task to solve this problem, (...) but I argue that this is false. Through the analysis of different theories concerning identity through time, I show how both ontology and metaphysics are concerned with the problem of diachronic identity, and how actually ontology turns out to be primary in solving the problem. (shrink)

This paper aims at investigating the influence of biblical concepts on Søren Kierkegaard’s theory of stages. Starting with a terminological analysis on the term ‘stage’, in which several biblical references resound, I shed light on the typological structure which lies at the core of the three spheres of existence according to Kierkegaard: the aesthetic one (“first immediacy”), the ethical one (“infinite requirement”), and the religious one (“fulfillment”). Eventually, I show that a study of Kierkegaard’s biblical background can help to understand (...) the paradoxical transition from each stage to next one, which can be conceived as the ontological passage from not-being to being (creation/Adam), from being to not being (annihilating power of the law/Moses), and from not being to being again (new creation/Christ). (shrink)

Until recently, an almost perfect parallelism seemed to hold between theories of identity through time and across possible worlds,as every account in the temporal case(endurantism,perdurantism, exdurantism) was mirrored by a twin account in the modal case (trans-world identity, identity-via-parts, identity-via-counterparts). Nevertheless, in the recent literature, this parallelism has been broken because of the implementation in the debate of the relation of location. In particular, endurantism has been subject to a more in-depth analysis, and different versions of it, corresponding to different (...) ways an entity can be located in time, emerged. In this article, we provide a precise map of the conceptions at stake, complete the debate by introducing a version of endurantism not yet considered in the debate — we call transcendentism — and show that it allows us to provide an effective interpretation of the relation of trans-world identity and an intuitive solution in the temporal case. (shrink)

This paper defends stage theory against the argument from diachronic counting. It argues that stage theorists can appeal to quantifier domain restriction in order to accommodate intuitions about diachronic counting sentences. Two approaches involving domain restriction are discussed. According to the first, domains of counting are usually restricted to stages at the time of utterance. This approach explains intuitions in many cases, but is theoretically costly and delivers wrong counts if diachronic counting is combined with fission or fusion. On the (...) second approach, domains of counting are usually restricted in an indeterminate way, so as to include at most one member of any maximal class of counterpart-interrelated stages (with respect to a certain utterance). This view can accommodate all the relevant intuitions about counting sentences, and it fits well with a new stage-theoretic view of reference that allows speakers to refer to both present and past stages. (shrink)

I introduce a puzzle about contact and de re temporal predication in relativistic spacetime. In particular, I describe an apparent counterexample to the following principle, roughly stated: if B is never in a position to say ‘I was touching A, I am touching A, and I will be touching A’, then (time travel aside) A is never in a position to say ‘I was touching B, I am touching B, and I will be touching B’. In the case I present, (...) the most that A is ever in a position to say is: ‘I am now touching B, but this is the only instant at which this will ever be so’. B, on the other hand, can say: ‘I was formerly touching A, I am currently touching A, and I will in the future be touching A’. (And neither object is a time traveler.). (shrink)

In the contemporary debate about the nature of persistence, stage theory is the view that ordinary objects (artefacts, animals, persons, etc.) are instantaneous and persist by being suitably related to other instantaneous objects. In this paper I focus on the issue of what stage theorists should say about the semantics of ordinary proper names, like ‘Socrates’ or ‘London’. I consider the remarks that stage theorists actually make about this issue, present some problems they face, and finally offer what I take (...) to be the best alternative available for them. (shrink)

Most contemporary metaphysicians are sceptical about the reality of familiar objects such as dogs and trees, people and desks, cells and stars. They prefer an ontology of the spatially tiny or temporally tiny. Tiny microparticles 'dog-wise arranged' explain the appearance, they say, that there are dogs; microparticles obeying microphysics collectively cause anything that a baseball appears to cause; temporal stages collectively sustain the illusion of enduring objects that persist across changes. Crawford L. Elder argues that all such attempts to 'explain (...) away' familiar objects project downwards, onto the tiny entities, structures and features of familiar objects themselves. He contends that sceptical metaphysicians are thus employing shadows of familiar objects, while denying that the entities which cast those shadows really exist. He argues that the shadows are indeed really there, because their sources - familiar objects - are mind-independently real. (shrink)

According to Sider’s stage theory a subject about to undergo personal fission should expect to experience each outcome simultaneously as distinct persons. How is the subject to make sense of this ? I argue that their most paradigmatically self-interested future-directed behaviour, betting for personal gain, ought to be exactly the same as in equivalent games of chance where the possible outcomes correspond to the fission output branches. So this novel form of expectancy, albeit strange, can be a reliable guide to (...) action. (shrink)

.What are the truth-makers for the claims we make about the ways familiar objects persist across change?“Stage theory” has come to be recognized as an alternative to endurantism and perdurantism. It locates the truth-makers in properties possessed by momentary object-stages and in relations between suitably propertied objectstages. This paper argues that stage theory needs tightening up: momentary stages are too short to possess by themselves the requisite properties, and relations to other stages cannot remedy the defect. Fixing this problem requires (...) reconstruing stage theory. It then is the position that all claims of persistence are true only when we are speaking loosely; in philosophical strictness, nothing persists. What stage theory then endangers is neither endurantism nor perdurantism—these now have no subject-matter—but recent efforts to argue that the essence/accident distinction is as objective as persistence itself. But even reconstrued stage theory fails. (shrink)

In this paper I explore how the tenseless copula is to be interpreted in sentences of the form “a is F at t”, where “a” denotes a persisting, changeable object, “F” stands for a prima facie intrinsic property and “t” for a B-time. I argue that the interpretation of the copula depends on the logical role assigned to the time clause. Having rejected the idea that the time clause is to be treated as a sentence operator, I argue: that if (...) “at t” is thought of as being associated with “a” or “F”, then the tenseless copula is most plausibly read as an “is” simpliciter; and that if “at t” is treated as being associated with the copula, then the tenseless copula is most plausibly understood as expressing a disjunction of tensed copulas. I end the paper by explaining the importance of the issue. I indicate the ramifications interpretation of the tenseless copula has for the so-called problem of temporary intrinsics. (shrink)

Roache has raised a new objection to cohabitation theories of personal fission. According to these theories, in cases of personal fission the pre-fission body is cohabited by (at least) two persons. She claims such cohabitants cannot be concerned for their survival in the way ordinary non-cohabitants can. I will offer criticism of Roache’s argument and conclude she doesn’t establish this claim.

Stage theorists invoke the idea of counterpart relations to make sense of how objects are able to persist despite their claim that an object is identical with a single instantaneous stage. According to stage theorists, an object persists if and only if it has a later counterpart that bears the appropriate counterpart relation of identity to it. Whilst objects can and do persist, stages cannot and do not. This seems to amount to a refutation of Leibniz’s law. Stage theorists think (...) that the nature of the counterpart relation invoked depends on how it is that the object is referred to. In this paper, I argue that the context sensitivity that they invoke here gives stage theorists a response to the Leibniz’s Law Problem. (shrink)

The eternalist endurantist and perdurantist theories of persistence through time come in various versions, namely the two versions of perdurantism: the worm view and the stage view , and the two versions of endurantism: indexicalism and adverbialism . Using as a starting point the instructive case of what is depicted by photographs, I will examine these four views, and compare them, with some interesting results. Notably, we will see that two traditional enemies—the perdurantist worm view and the endurantist theories—are more (...) like allies : they are much less different than what is usually thought, and some alleged points of central disagreement fall prey to closer scrutiny. The aim of this paper is to examine carefully all those points, and to call attention to the places where the real differences between these views lie. I will then turn to the perdurantist stage view, and claim that with respect to some central issues it is the view that is the most different from the other three, but that in some places the reason why it different is also the reason why it is less satisfactory. (shrink)

This thesis is about the conceptualization of persistence of physical, middle-sized objects within the theoretical framework of the revisionary ‘B-theory’ of time. According to the B-theory, time does not flow, but is an extended and inherently directed fourth dimension along which the history of the universe is ‘laid out’ once and for all. It is a widespread view among philosophers that if we accept the B-theory, the commonsensical ‘endurance theory’ of persistence will have to be rejected. The endurance theory says (...) that objects persist through time by being wholly present at distinct times as numerically the same entity. Instead of endurantism, it has been argued, we have to adopt either ‘perdurantism’ or the ‘stage theory’. Perdurantism is the theory that objects are four-dimensional ‘space-time worms’ persisting through time by having distinct temporal parts at distinct times. The stage theory says that objects are instantaneous temporal parts (stages) of space-time worms, persisting by having distinct temporal counterparts at distinct times. In the thesis, it is argued that no good arguments have been provided for the conclusion that we are obliged to drop the endurance theory by acceptance of the B-theory. This conclusion stands even if the endurance theory incorporates the claim that objects endure through intrinsic change. It is also shown that perdurantism and the stage theory come with unwelcome consequences. -/- Paper I demonstrates that the main arguments for the view that objects cannot endure in B-time intrinsically unchanged fail. Papers II and III do the same with respect to the traditional arguments against endurance through intrinsic change in B-time. Paper III also contains a detailed account of the semantics of the tenseless copula, which occurs frequently in the debate. The contention of Paper IV is that four-dimensional space-time worms, as traditionally understood, are not suited to take dispositional predicates. In Paper V, it is shown that the stage theory needs to introduce an overabundance of persistence-concepts, many of which will have to be simultaneously applicable to a single object (qua falling under a single sortal), in order for the theory to be consistent. The final article, Paper VI, investigates the sense in which persistence can, as is sometimes suggested, be a ‘conventional matter’. It also asks whether alleged cases of ‘conventional persistence’ create trouble for the endurance theory. It is argued that conventions can only enter at a trivial semantic level, and that the endurance theory is no more threatened by such conventions than are its rivals. (shrink)

An alternative to the standard endurance/perdurance accounts of persistence has recently been developed: the stage theory (Sider, T. Four-Dimensionalism: an Ontology of Persistence and Time. Oxford: Oxford University Press, 2001; Hawley, K. How Things Persist. Oxford: Oxford University Press, 2001). According to this theory, a persisting object is identical with an instantaneous stage (temporal part). On the basis of Leibniz's Law, I argue that stage theorists either have to deny the alleged identity (i.e., give up their central thesis) or hold (...) that stages are both instantaneous and continuants. I subsequently show that, although stage theory is flexible enough to accommodate the latter claim, the cost for accommodating it is an excessive proliferation of persistence concepts. (shrink)

Most four-dimensionalists, including both worm and stage theorists, endorse mereological universalism, the thesis that any class of objects has a fusion. But the marriage of fourdimensionalism and universalism is unfortunate and unprofitable: it creates a recalcitrant problem for stage theory’s account of lingering properties, such as writing ‘War and Piece’ and traveling across the tennis court, which take time to be instantiated. This makes it necessary to impose a natural restriction on diachronic composition.

On stage theory, ordinary continuants are instantaneous stages which persist by exduring—by bearing temporal counterpart relations to other such stages. Exduring objects lack temporal extension and there is a sense in which they are wholly present at multiple instants. How then is exdurance different from endurance? I offer a definition of ‚exdurance’ that clearly sets it apart from other modes of persistence.

A discussion of Ted Sider's argument for perdurantism on the grounds of the possibility of timeless worlds.

David Lewis's cohabitation theory suffered damaging criticism from Derek Parfit. Though many have defended versions of Lewis's theory Parfit's criticism has not been answered. This paper shows how to defend the cohabitation theory against Parfit's criticism.

How do ordinary objects persist through time and across possible worlds ? How do they manage to have their temporal and modal properties ? These are the questions adressed in this book which is a "guided tour of theories of persistence". The book is divided in two parts. In the first, the two traditional accounts of persistence through time (endurantism and perdurantism) are combined with presentism and eternalism to yield four different views, and their variants. The resulting views are then (...) examined in turn, in order to see which combinations are appealing and which are not. It is argued that the 'worm view' variant of eternalist perdurantism is superior to the other alternatives. In the second part of the book, the same strategy is applied to the combinations of views about persistence across possible worlds (trans-world identity, counterpart theory, modal perdurants) and views about the nature of worlds, mainly modal realism and abstractionism. Not only all the traditional and well-known views, but also some more original ones, are examined and their pros and cons are carefully weighted. Here again, it is argued that perdurance seems to be the best strategy available. (shrink)

On the B-theory of time, the experiences we have throughout our conscious lives have the same ontological status: they all tenselessly occur at their respective dates. But we do not seem to experience all of them on the same footing. In fact, we tend to believe that only our present experiences are real, to the exclusion of the past and future ones. The B-theorist has to maintain that this belief is an illusion and explain the origin of the illusion. The (...) paper argues that this cannot be properly done unless one rejects endurantism in favor of the stage view of persistence. (shrink)

The metaphysical explanations of genidentity are very important both for scien-tific researches and for everyday human activities. Endurantism, perdurantism and exdurantism (stage view and point-eventism) are the standard metaphysical theo-ries, which provide descriptions and explanations of relations of change and persistence. The descriptions and explanations in question give simultaneously the truth-conditions for statements about an identity of objects, which persist and undergo changes in time. The main aim of the paper is to formulate the above-mentioned metaphysical stances and to give (...) the general account of the relation of genidentity within a conceptual framework of these theories. The second aim is to provide a suitable reconstruction of criteria of genidentity, which are appropriate for the three metaphysical doctrines. (shrink)

Theodore Sider has recently produced an argument which he takes to show that three-dimensionalism is incompatible with the possibility of time travel. I wish to argue that there is indeed a problem for the three-dimensionalist who wishes to countenance time travel, but that Sider has misdiagnosed it. I show why his putative challenge fails, and furthermore that if it were to succeed this would be as problematic for a wide class of four-dimensionalist positions, including Sider’s own, as it would be (...) for three-dimensionalism. Finally, I present the problem that the possibility of time travel genuinely poses for the three-dimensionalist. (shrink)

Harold Noonan has recently argued (2003) that one of Lewis’s (1983: 76– 77) arguments for the view that objects persist by perduring is flawed. Lewis’s argument can be divided into two main sections, the first of which attempts to show that it is possible that there exists a world of temporal parts or stages, and the second, which attempts to show that our world is such a world. Noonan claims that there is a flaw in each of these two stages.We (...) argue to the contrary. (shrink)

How do the familiar concrete objects of common sense persist through time? The four-dimensionalist argues that they perdure, that is, they persist through time by having temporal parts at each of the times at which they exist. The three-dimensionalist, on the other hand, holds that ordinary concrete objects endure; they lack an additional temporal dimension and persist, instead, by being “wholly present” at each of the times at which they exist.