In this volume, thirteen philosophers contribute new essays analyzing the criteria for personal identity and their import on ethics and the theory of action: it presents contemporary treatments of the issues discussed in Personal Identity, edited by John Perry (University of California Press, 1975).

The aim of this essay is to introduce philosophers of science to some recent philosophical discussions of the nature and origin of the direction of time. The essay is organized around books by Hans Reichenbach, Paul Horwich, and Huw Price. I outline their major arguments and treat certain critical points in detail. I speculate at the end about the ways in which the subject may continue to develop and in which it may connect with other areas of philosophy.

The paper proposes a simple method for constructing ontological theories—an ‘ontology generator’. It shows that such a generator manages to produce major existing ontological theories, e.g., Realism, Nominalism, Trope theory, Bundle theory, Perdurantism, Endurantism, Possibilism, Actualism and more. It thus turns out, surprisingly, that all these seemingly unrelated different ontological theories that were designed by thinkers hundreds of years apart, can all be generated using the same simple mechanism. Moreover, this same generator manages to produce entirely novel ontological theories, that (...) fare no worse than existing ones in meeting the same common metaphysical challenges. (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)

According to three-dimensionalism, objects persist in time by being wholly present at each time they exist; on the contrary, four-dimensionalism asserts that objects persist by having different temporal parts at different times or that they are instantaneous temporal parts of four-dimensional aggregates. Le Poidevin has argued that four-dimensionalism better accommodates two common assumptions concerning persistence and continuity; namely, that time itself is continuous and that objects persist in time in a continuous way. To this purpose, he has offered two independent (...) arguments, each of which moves from a different understanding of continuity. In this paper, both of Le Poidevin’s arguments will be discussed and rejected. (shrink)

Four-dimensionalism, or perdurantism, the view that temporally extended objects persist through time by having (spatio-)temporal parts or stages, includes two varieties, the worm theory and the stage theory. According to the worm theory, perduring objects are four-dimensional wholes occupying determinate regions of spacetime and having temporal parts, or stages, each of them confined to a particular time. The stage theorist, however, claims, not that perduring objects have stages, but that the fundamental entities of the perdurantist ontology are stages. I argue (...) that considerations of special relativity favor the worm theory over the stage theory. (shrink)

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.

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)

An introduction to the theories of endurantism and perdurantism, and persistence more broadly.

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 assessment of the similarities and differences between space and time has played an important part in the development of the views of a number of philosophers about time. Examples of statements about time are compared with allegedly corresponding statements about space to give us analogies and disanalogies according to whether the statements have the same or different truth values. But what are the general principles on which such comparisons are based? In particular, according to what criteria are corresponding sentences (...) paired off? Are there any such general criteria? And if so, do they already presuppose a substantial commitment to one or other of the points of view at issue where analogies and disanalogies are discussed? This paper is concerned with two specific proposals for criteria of correspondence, one due to Richard Gale (1968, 1969) and James Garson (1969), which is rejected, and the other tentatively advanced in its place. (shrink)