An encyclopedia entry which covers various revisionary conceptions of which macroscopic objects there are, and the puzzles and arguments that motivate these conceptions: sorites arguments, the argument from vagueness, the puzzles of material constitution, arguments against indeterminate identity, arguments from arbitrariness, debunking arguments, the overdetermination argument, and the problem of the many.

A possible solution is offered to help resolve the “two times problem” regarding the veridical and illusory nature of time. First it is recognized that the flow (passage) of time is part of a wider array of temporal experiences referred to as manifest time, all of which need to be reconciled. Then, an information gathering and utilizing system (IGUS) model is used as a basis for a view of manifest time. The model IGUS robot of Hartle that solves the “unique (...) present” debate is enhanced with veridical and (corresponding) illusory components of not only the flow of time but also the larger entity of manifest time, providing a dualistic IGUS robot that represents all of the important temporal experiences. Based upon a variety of prior experiments, that view suggests that the veridical system is a reflection of accepted spacetime cosmologies and through natural selection begets the illusory system for functional purposes. Thus, there are not two opposing times, one outside and one inside the cranium. There is just one fundamental physical time which the brain developed, now possesses and is itself sufficient for adaption but then enhances. The illusory system is intended to provide a more satisfying experience of physical time, and better adaptive behavior. Future experiments to verify that view are provided. With a complete veridical system of temporal experiences there may be less need to reify certain temporal experiences so that the two times problem is less of a problem and more of a phenomenon. (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.

This paper argues that, in light of certain scenarios involving time travel, Sider’s definition of ‘instantaneous temporal part’ cannot be accepted in conjunction with a semantic thesis that perdurantists often assume. I examine a rejoinder from Sider, as well as Thomson’s alternative definition of ‘instantaneous temporal part’, and show how neither helps. Given this, we should give up on the perdurantist semantic thesis. I end by recommending that, once we no longer accept such semantics, we should accept a new set (...) of definitions, which are superior in certain respects to Sider’s original set. (shrink)

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)

In the current debate on how ordinary objects persist through time, more than one philosopher has endorsed the following two theses: stage theory and diachronic universalism. In this paper, I would like to offer a solution to the problem that Balashov poses to the joint acceptance of these theses. I will also offer a number of reasons why, even if it is not necessary to undermine Balashov’s counterexamples, stage theorists can, without making their theory less appealing, reject Balashov’s understanding of (...) sorts, which plays a crucial role in his criticisms of stage universalism. (shrink)

Many bioethical arguments rely implicitly on the assumption that the concept of “human part” is one on which everyone must agree, because it is unambiguous. But various parties interpret this “unambiguous” term in incompatible ways, leading to contention. This article is an informal presentation of a topomereological system on whose preferred interpretation several distinct but related meanings of “human part” can be isolated: part of a human body, part of the completion of a human body, and part of a human (...) being. A case is analyzed (the first total artificial heart (TAH) implantation), demonstrating in the process much of the apparatus of the system. By means of a casuistic methodology, the analysis is translated into recommendations for the ethical conduct of future TAH research. The more general conclusion, however, is that formal methods may provide useful tools for clarifying thought processes and organizing arguments in debates over bioethical issues. (shrink)