Sceptics about substantial disputes in ontology often argue that when two philosophers seem to disagree on a quantified claim, they are actually equivocating on the notion of existence that they are using. When temporal elements play a central role, as in the debate between presentists and eternalists, the hypothesis of an equivocation with respect to existence acquires more plausibility. However, the anti-sceptic can still argue that this hypothesis is unjustified.

Precis of my book by this title, for a symposium.

Presentism is typically characterised as the thesis that everything is present, and therefore there are no dinosaurs or Martian presidential inaugurations. Putting aside the vexed question of exactly what it is to be present in this context, this thesis seems quite straightforward. However, a number of authors—such as Merricks, Lombard, Meyer, Tallant and Sakon —have argued that Presentism so characterised is either trivially true or false even by Presentist lights. This is the so-called Triviality Argument against Presentism. In this paper (...) I show that three of the four premises of the Triviality Argument are plausibly false. I conclude that Presentists have nothing to fear from the Triviality Argument. (shrink)

We argue that sensitivity to the distinction between the tensed notion of being something and the tensed notion of being located at the present time serves as a good antidote to confusions in debates about time and existence, in particular in the debate about how to characterise presentism, and saves us the trouble of going through unnecessary epicycles. Both notions are frequently expressed using the tensed verb ‘to exist’, making it systematically ambiguous. It is a commendable strategy to avoid using (...) that verb altogether in these contexts and to use quantification and a location predicate instead. (shrink)

This monograph is a detailed study, and systematic defence, of the Growing Block Theory of time (GBT), first conceived by C.D. Broad. The book offers a coherent, logically perspicuous and ideologically lean formulation of GBT, defends it against the most notorious objections to be found in the extant philosophical literature, and shows how it can be derived from a more general theory, consistent with relativistic spacetime, on the pre-relativistic assumption of an absolute and total temporal order. -/- The authors devise (...) axiomatizations of GBT and its competitors which, against the backdrop of a shared quantified tense logic, significantly improves the prospects of their comparative assessment. Importantly, neither of these axiomatizations involves commitment to properties of presentness, pastness or futurity. The authors proceed to address, and defuse, a number of objections that have been marshaled against GBT, including the so-called epistemic objection according to which the theory invites skepticism about our temporal location. The challenge posed by relativistic physics is met head-on, by replacing claims about temporal variation by claims about variation across spacetime. -/- The book aims to achieve the greatest possible rigor. The background logic is set out in detail, as are the principles governing the notions of precedence and temporal location. The authors likewise devise a novel spacetime logic suited for the articulation, and comparative assessment, of relativistic theories of time. The book comes with three technical appendices which include soundness and completeness proofs for the systems corresponding to GBT and its competitors, in both their pre-relativistic and relativistic forms. -/- The book is primarily directed at researchers and graduate students working on the philosophy of time or temporal logic, but is of interest to metaphysicians and philosophical logicians more generally. (shrink)

Temporal ontology is the part of ontology involving the rival positions of presentism, eternalism, and the growing block theory. While this much is clear, it’s surprisingly difficult to elucidate the substance of the disagreement between presentists and eternalists. Certain events happened that are not happening now; what is it to disagree about whether these events exist? In spite of widespread suspicion concerning the status and methods of analytic metaphysics, skeptics’ doubts about this debate have not generally been heeded, neither by (...) metaphysicians, nor by philosophers of physics. This paper revisits the question in the light of prominent elucidation attempts from both camps. The upshot is that skeptics were right to be puzzled. The paper then explores a possible re-interpretation of positions in temporal ontology that links it to normative views about how we should live as temporal beings. (shrink)

Temporaryism—the view that not always everything always exists—comes in two main versions: presentism and expansionism (aka the growing block theory of time). Both versions of the view are commonly formulated using the notion of being present, which we, among others, find problematic. Expansionism is also sometimes accused of requiring extraordinary conceptual tools for its formulation. In this paper, we put forward systematic characterizations of presentism and expansionism which involve neither the notion of being present nor unfamiliar conceptual tools. These characterizations (...) are full-blown logics, each logic comprising an axiomatic proof system and an intuitive semantics with respect to which the system is both sound and complete. (shrink)