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.

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 article I reply to Fleming׳s response to my ‘Time and quantum theory: a history and a prospectus.’ I take issue with two of his claims: (i) that quantum theory concerns the (potential) properties of eternally persisting objects; (ii) that there is an underdetermination problem for Positive Operator Valued Measures (POVMs). I advocate an event-first view which regards the probabilities supplied by quantum theory as probabilities for the occurrence of physical events rather than the possession of properties by persisting (...) objects. (shrink)

Please imagine a long fuse hanging down from the ceiling. It is a carefully woven tube of fabric that holds a core of gunpowder. We note that it is beautifully made, with brightly colored threads intertwined with the coarser bare cotton. It a masterpiece of the modern weaver's art.

We ponder the question whether quantum physics has had any influence on philosophy, and if not, whether it ought to have had any. Answers to these questions are provided, and they turn out to depend onwhichbranch of the tree of philosophy we sweep, sway and swing, and evenwhichtwig of the branch we touch when we sweep, sway and swing.

This paper investigates the use of theories of mechanics to provide answers to questions in the metaphysics of spatial location and persistence. Investigating spatial location, I find that in classical physics bodies pertend the region of space at which they are exactly located, while a quantum system spans a region at which it is exactly located. Following this analysis, I present a ‘no-go’ result which shows that quantum mechanics restricts the available options for locational persistence theories in an interesting way: (...) it demonstrates that the spatiotemporal path of a persisting thing is discrete in time. This leads to unpalatable consequences for both perdurantists and endurantists. In particular, I argue that Butterfield's ‘anti-pointilliste’ perdurantism is ruled out, and show that endurantists relying on immanent causation run into trouble. I conclude by suggesting the revival of Whitehead's alternative mode of persistence called ‘reiteration.’. (shrink)

I explicate and defend a non-standard theory of persistence, which I calltransdurantism. In short, transdurantism is the view is that objects persist by being temporally extended simples. Transdurantism is sometime misrepresented as a version of endurantism. Other times, transdurantism is misrepresented as a version of perdurantism. But I argue transdurantism must be disambiguated from perdurantism and endurantism—when endurantism, perdurantism, and transdurantism are properly construed, transdurantism stands apart from the other theories of persistence and we can better understand the distinct burdens (...) they each bear. I also argue that the transdurantist is capable of handling several key problems found in the persistence literature at least as well as her rivals, but she does face her own unique challenges. (shrink)

The question of how to characterise the diachronic identity of a concrete particular within a metaphysical framework is the problem of persistence. There are two major theories, Endurantism and Perdurantism affirming a problem of persistence for concrete particulars. While Endurantism, on the one hand, argues that concrete particulars persist wholly, Perdurantism, on the other hand, argues that they persist as temporal slices. This paper argues that neither Endurantism nor Perdurantism adequately characterise the persistence of concrete particulars. This is because there (...) is an impasse between these two major theories of persistence. The article concludes that hence, there is a need for another hypothesis or theory of persistence to address the problem of persistence in metaphysics. This paper broadens the discourse on persistence of concrete objects beyond a debate between Endurantism and Perdurantism. The paper uses the methods of conceptual analysis and philosophical argumentation. (shrink)