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.

ABSTRACTA structure is temporally gunky just in case all of its temporal parts have proper temporal parts. Joshua Stuchlik [2003] objects to the stage theory of persistence from temporal gunk by ar...

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.

The present work explores various ways in which contingent evidence can impact metaphysics, while advocating that, just as a scientific realist allows for ampliative inferences to the unobservable, ampliative inferences from possible evidence can warrant possibility claims that lie beyond the reach of sensorial imagination. In slogan form: possible evidence is a guide to possibility. Drawing on Shoemaker’s (1969) argument for the possibility of time without change, I advocate the following principle: If there is a possible world at which the (...) observable facts make it objectively reasonable to conclude that p, then we should conclude that p is possibly true. This provides a route to contingentism in metaphysics, for, if one considers that there are worlds in which the observable facts make it objectively reasonable to conclude that p, and worlds in which the observable facts make it objectively reasonable to conclude that not-p, then my principle tells us that we should conclude that possibly-p and possibly not-p, i.e. that p is contingent. This contingency in what is reasonable to conclude, I suggest, occurs most saliently in debates where evidence of phenomenal experience and empirical science are marshalled to support one theory over another. I also explore some consequences of taking possible evidence to be a guide to possibility in this way, among them being an interesting modal analogue of the lottery paradox. (shrink)

This thesis is composed of three essays on the perdurantist approach to persistence and identity over time. In Chapter 1, I discuss how the following papers are to be understood as parts of a unified perdurantist account of persistence over time. This chapter also outlines some of my philosophical assumptions and provides some background information about the metaphysics of persistence. In Chapter 2, I respond to the objection that the worm theory is unable to account for our intuitions about ordinary (...) counting sentences. I do this by invoking the standard linguistic phenomenon of covert quantifier domain restriction and supplementing the worm theory with situation semantics. My version of the worm theory makes our intuitive judgements come out true, and it does so well enough that there is no need to adopt the stage theory or revisionary theories of counting. Furthermore, my version of the worm theory offers a unified account of event- and object-related counting. Chapter 3 focuses on a commonly neglected difference between different kinds of perdurantism, which are differences in mereological priority. I discuss three different views: parts-first perdurantism, no-priority perdurantism, and wholes-first perdurantism. I briefly outline all three views and some of the motivations for each of them. I fend off objections from and motivations for no-priority perdurantism. I also contend that intraperdurantist debates about phenomenology ought not to be framed with respect to these forms of perdurantism. Instead, I suggest that the relativity of simultaneity presents an interesting scenario for parts-first and wholes-first perdurantists. I respond to Thomas Pashby’s arguments against the doctrine of temporal parts in Chapter 3. Pashby argues that metaphysicians ought to give an account of how quantum systems persist over time and that nonrelativistic quantum mechanics is incompatible with perdurantism. I contend that his arguments rely on controversial, non-standard assumptions about the existence and importance of time observables. I demonstrate that perdurantists have no problem giving an account of how quantum systems persist over time in reference to an external time parameter. Finally, I conclude with a summary of my arguments and some thoughts about directions for future research. (shrink)

In this thesis, I examine the metaphysical debate between the A-theory and the B-theory of time, first by elaborating upon its proper characterization, and then by examining the sorts of evidence that are often thought to be germane to it. This debate, as I see it, is about whether or not time passes in any objective sense: the A-theory holds that it does, while the B-theory holds that it does not. I identify two opposing conceptions of time—that of the “time (...) of ordinary experience” on one hand, and that of “scientific time” on the other—and argue that the tension between them is the driving force behind this debate. I then examine two aspects of “evidence” from the time of ordinary experience: the phenomenological experience of time and the linguistic experience of time. It is often supposed, by both A- and B-theorists alike, that these sorts of evidence lend credence to the A-theory of time, since ordinary experience suggests that time passes. I hope to discredit this presumption, and so challenge the very framework in which this debate is so often carried out. In particular, by closely examining both of these kinds of experience—phenomenological and linguistic—in turn, I hope to provide a partial argument to the effect that the ordinary experience of time as a whole does not favour the A-theory over the B-theory of time. In the case of the phenomenological evidence, this is because the A-theory is just as inconsistent with such evidence as is the B-theory of time; in the case of the linguistic evidence, this is because the B-theory is equally consistent with such evidence as is the A-theory of time, particularly once it is revealed that a certain key assumption is tacitly accepted by both sides of the debate. Because of the popularity of the claim that the ordinary experience of time favours the A-theory, I take this conclusion to be something of a modest defence for the B-theory of time. (shrink)