This paper offers a new formulation of the “Hilbert's Hotel Argument” (HHA) which is superior to existing formulations because it (1) demonstrates that HH is logically impossible in the concrete world, (2) takes into account the need to consider the assumptions of HHA, and (3) offers a reply to an important objection concerning the validity of HHA. In addition, this paper contributes to the discussion by using the new HHA to defend a relevant difference between the past and the (...) future by demonstrating that the HHA applies to the former but not to the latter. Finally, this paper demonstrates the significance of metaphysical arguments such as the HHA for physical cosmology. (shrink)

This paper offers a new formulation of the “Hilbert's Hotel Argument” (HHA) which is superior to existing formulations because it (1) demonstrates that HH is logically impossible in the concrete world, (2) takes into account the need to consider the assumptions of HHA, and (3) offers a reply to an important objection concerning the validity of HHA. In addition, this paper contributes to the discussion by using the new HHA to defend a relevant difference between the past and the (...) future by demonstrating that the HHA applies to the former but not to the latter. Finally, this paper demonstrates the significance of metaphysical arguments such as the HHA for physical cosmology. (shrink)

Eternalism is the view that the past, the present and the future exist simpliciter. A typical argument in favor of this view leans on the relativity of simultaneity. The ‘equally real with’ relation is assumed to be transitive between spacelike separated events connected by hyperplanes of simultaneity. This reasoning is in tension with the conventionality of simultaneity. Conventionality indicates that, even within a specific frame, simultaneity is based on the choice of the synchronization parameter. Hence the argument for (...) eternalism is compromised. This paper lays out alternative eternalist strategies which do not hinge on hyperplanes. While we lack a rigorous proof for eternalism, there are still cogent reasons to prefer eternalism over presentism. (shrink)

Eternalism is a metaphysical view regarding the nature of time. It posits the equal existence of all times: the past, the present, and the future. Every event, from the big bang to the heat death of the universe, including our births and deaths, is equally real. -/- Under standard eternalism, temporal locations are somewhat akin to spatial locations. No place is exclusively real. When someone says that they stand ‘here’, it is clear that the term ‘here’ refers (...) to their position. ‘Back’ and ‘front’ exist as well. Eternalists stress that ‘now’ is indexical in a similar way. It is equally real with ‘past’ and ‘future’. Events are classified as past, present, or future from some perspective. -/- Eternalism is contrasted with presentism, which maintains that only present things exist and with the growing block view (also known as possibilism or no-futurism), which holds that past and present things exist but not future ones. The moving spotlight view suggests that all times exist but that the present is the only actual time. This view can be termed eternalist, but it preserves a non-perspectival difference between past, present, and future by treating tense as absolute. Additionally, the moving spotlight view retains some characteristics of presentism by maintaining that the ‘now’ is unique and privileged. -/- Broadly speaking, presentism is a common-sensical view, and so aligns with our manifest image of time. This view is, however, at odds with the scientific image of time. The primary motivation for eternalism arises from orthodox interpretations of the theories of relativity. According to them, simultaneity is relative, not absolute. This implies that there is no universal ‘now’ stretched out across the entire universe. One observer’s present can be another’s past or future. Assuming the universe is four-dimensional spacetime, then all events exist unconditionally. -/- The classical argument for eternalism was devised in the 1960s by Rietdijk in 1966 and Putnam in 1967, with subsequent follow-ups by Maxwell in 1985, Penrose in 1989, and Peterson and Silberstein in 2010. This argument and its ramifications remain the subject of ongoing debate. They shall be further explored in this entry, including their relation to other issues in the metaphysics of time and the philosophy of physics. (shrink)

This paper has three main sections. The first section provides a general characterisation of presentism, eternalism and growing blockism. It presents a pair of core, defining claims that jointly capture each of these three views. This makes clear the respects in which the different views agree, and the respects in which they disagree, about the nature of time. The second section takes these characterisations and considers whether we really do have three distinct views, or whether defenders of these views (...) are somehow talking past one another when they claim to disagree. The third section looks at the key objections to each view and considers some of the replies that can be made to those objections. The paper concludes by offering some thoughts about how future research might help us resolve the debate between defenders of these three views. (shrink)

In his 2004 paper ‘Tensed Quantifiers’, David Lewis presented an apparently powerful case for eternalism by arguing that we cannot account for the truth-conditions of sentences like ‘There have been forty-four presidents of the United States’ and ‘There will be five more presidents of the United states’ and maintain a non-revisionary attitude towards their truth-values, without committing to the existence of ‘past’ and ‘future’ things. Related arguments can be found in works by Ted Sider, and by Zoltan Gendler (...) Szabó. We can call the fully developed form of this argument the Argument from Semantics. In this paper, I counter the AfS by showing that these truth-conditions can be captured without commitment to the existence of things—such as Socrates and Abraham Lincoln—which we take to have existed but not to exist, or things—like the par.. (shrink)

Eternalist tensism is the thesis that tense is an objective feature of reality as it is in itself and that all times, whether past, present, or future, are equally real. I develop an argument from qualitative change in favor of tensism and defend eternalism from an argument from fatalism.

Eternalism, the view that what we regard locally as being located in the past, the present and the future equally exists, is the best ontological account of temporal existence in line with special and general relativity. However, special and general relativity are not fundamental theories and several research programs aim at finding a more fundamental theory of quantum gravity weaving together all we know from relativistic physics and quantum physics. Interestingly, some of these approaches assert that time is (...) not fundamental. If time is not fundamental, what does it entail for eternalism and the standard debate over existence in time? First, I will argue that the non-fundamentality of time to be found in string theory entails standard eternalism. Second, I will argue that the non-fundamentality of time to be found in loop quantum gravity entails atemporal eternalism, namely a novel position in the spirit of standard eternalism. (shrink)

The distinction between presentism and eternalism is usually sought in some formula like ‘Only presently existing things exist’ or ‘Past, present, and future events are equally real’. I argue that ambiguities in the copula prevent these slogans from distinguishing significant opposed positions. I suggest in addition that one can find a series of significant distinctions if one takes spacetime structure into account. These presentisms and eternalisms are not contradictory. They are complementary elements of a complete naturalistic philosophy of (...) time. (shrink)

In this discussion I argue that, given the possibility of travel to the past, eternalists face a dilemma. They must choose between fatalism and the denial of an intuitive claim about what a traveller to the past cannot do. The eternalist should deny this seemingly intuitive claim which is in fact a version of fatalism about the past.

This chapter discusses the metaphysical view referred to by Harry Silverstein as “four-dimensionalism,” but referred to in this chapter as “eternalism.” In contrast to presentism, eternalism posits that purely past and purely future objects and events exist. If a person goes out of existence at the moment of death, the problem arises as to how death is bad for its victim. According to Silverstein, this problem arises from the truth of the “Values Connect with Feelings” thesis, according (...) to which it must be possible for someone to have feelings about a thing in order for that thing to be bad for that person. The badness of death may entail eternalism, but it is for an entirely different reason. Eternalism must be true in order for there to be a time at which death is bad for its victim. These two conflicting views are discussed in this chapter. (shrink)

In the early twentieth century, many philosophers in America thought that time should be taken seriously in one way or another. George P. Adams (1882-1961) argued that the past, present and future are all real but only the present is actual. I call this theory ‘actualist eternalism’. In this paper, I articulate his novel brand of eternalism as one piece of his metaphysical system and I explain how he argued for the view in light of the best (...) explanations of temporal experience and the present. I argue that his exploitation of analogies between time and modality offer some lessons for current debates about time such as the importance of providing a temporal epistemology. I also extract what I call the temporal boundary problem and argue that it gives rise to an unaddressed challenge for presentists and growing block theorists. (shrink)

In this paper I argue that the debate between the so-called “presentists” – according to whom only the present is real – and the “eternalists”, according to whom past present and future are equally real, has no ontological significance. In particular, once we carefully distinguish between a tensed and a tenseless sense of existence, it is difficult to find a single ontological claim on which the two parties could disagree. Since the choice of using a tense or a tenseless (...) language is dictated by purely pragmatic reasons, we should abstain from bringing to bear pseudo-debates generated by the “tensed” or the “tenseless theories” of time on the question of understanding the philosophical implications of contemporary spacetime theories, or notions like becoming, change and persistence in time. (shrink)

Suppose that at the moment of death, a person goes out of existence.1 This has been thought to pose a problem for the idea that death is bad for its victim. But what exactly is the problem? Harry Silverstein says the problem stems from the truth of the “Values Connect with Feelings” thesis (VCF), according to which it must be possible for someone to have feelings about a thing in order for that thing to be bad for that person (2000, (...) 122). But in order for a person to have feelings about a thing, the person and the thing must coexist in some way. Thus Silverstein feels compelled to endorse a metaphysical view he calls “four-dimensionalism,” but which I prefer to call “eternalism”: the view that purely past and purely future objects and events exist.2 I agree with Silverstein that the badness of death entails eternalism. But the reason is different. Eternalism must be true in order for there to be a time at which death is bad for its victim. Death is bad for its victim at all those times when the victim is worse off for having died: namely, the times when he would have been living a good life had that death not occurred.3 Silverstein rejects this view; he thinks there is something wrong with the very question of when death is bad for its victim. In what follows I argue that Silverstein has not shown the relevance of eternalism to VCF or the badness of death, and I defend my view about the time of death’s badness against Silverstein’s arguments. (shrink)

In this paper, I develop an argument against eternalism, which is similar to the widely discussed grounding problem for presentism. It has recently been argued by many that presentism should be rejected on grounds that its sparse ontology is not suited to underwrite the healthy dose of realism we all share about the past. My aim basically is to add a new twist to the debate, by showing that actually eternalists are no better off than their rivals. In (...) particular, I argue that the eternalist’s ontology does not have the appropriate shape to ground true propositions about the past. (shrink)

Ever since the now infamous comments made by Hermann Minkowski in 1908 concerning the proper way to view space-time, the debate has raged as to whether or not the universe should be viewed as a four-dimensional, unified whole wherein the past, present, and future are equally real or whether the views espoused by the possibilists, historicists, and presentists regarding the unreality of the future (and, for presentists, the past) are best. Now, a century after Minkowski’s proposed blockworld first (...) sparked debate, we seek a more conclusive argument in favor of the eternalist picture of space-time. Utilizing an argument based on the relativity of simultaneity in the tradition of Putnam and Rietdijk and novel but reasonable assumptions as to the nature of “reality”, we will show that the past, present, and future are equally real, thus ruling out presentism and other theories of time that bestow special ontological status to the past, present, or future as untenable. Finally, we will respond to our critics who would suggest that: 1) there is no metaphysical difference between the positions of eternalism and presentism, 2) the present must be defined as the “here” as well as the “now”, or 3) presentism is correct and our understanding of relativity is incomplete because it does not incorporate a preferred frame. We call eternalist response 1 deflationary since it purports to dissolve or deconstruct the age-old debate between the two views and response 2 compatibilist because it does nothing to alter special relativity (SR) arguing instead that SR unadorned has the resources to save presentism. Response 3 we will call incompatibilism because it adorns SR in some way in order to save presentism a la some sort of preferred frame. We will show that neither move 1 nor 2 can save presentism and move 3 is not well motivated at this juncture except as an ad hoc device to refute eternalism. (shrink)

ABSTRACT The current analytical debate on time is full of attempts to adjudicate from a purely theoretical standpoint among competing temporal ontologies. Little attention has instead been devoted to the existential attitudes -- emotional or ethical -- that may lurk behind, or ensue from, the endorsement of one of them. Some interesting opinions have however been voiced regarding the two most prominent views in the arena, namely eternalism and presentism; it has been said that the former is nourished by (...) a fear of death, or more generally by a desire of preservation for whatever we find precious and valuable, and that the latter is fuelled by a propensity to reap whatever fruits the present brings, as enshrined in the carpe diem motto. This paper explores such a territory by focusing on the reality of past sentience, whether joyful or painful, and on the open future. The first part contrasts the reality of past sentience that comes with eternalism with the denial of this reality that follows from presentism, and argues that from an emotional, or perhaps even moral, standpoint the latter is preferable to the former. The second part clarifies why the eternalist must renounce the open future, whereas presentism is consistent with it, and considers how its rejection or acceptance, as the case may be, could be emotionally, or even morally, significant for our conception of ourselves as free agents. The conclusion offers a tentative proposal regarding which temporal ontology is superior from an existential perspective and some ruminations on the impact that all this may have on the theoretical side of the issue. (shrink)

In the current paper, I enter into debate with Marcin Tkaczyk and the chosen Anglo-Saxon analytic philosophers of religion to discuss the theological version of the problem of future contingents. I take into consideration some varieties of Ockhamism (retroactivism)—the position denying the temporal necessity (non-determination) of all past events and allowing some form of retroactivity. Strong Ockhamism postulates real retroactive causation, moderate Ockhamism limits it to the meanings of physical and psychical events, and weak Ockhamism replaces the notion of (...) retroactive causation with that of retroactive dependence. I compare different forms of retroactivism with eternalism (of Boethius, St. Anselm of Canterbury, and St. Thomas Aquinas) to show that the latter has significant advantage. At the same time, I point out that eternalism in its presentist and relativist version (proposed by Brian Leftow) avoids the objections put forward against it, and that, within such eternalism, the problem of future contingents does not arise. (shrink)

There are many questions we can ask about time, but perhaps the most fundamental is whether there are metaphysically interesting differences between past, present and future events. An eternalist believes in a block universe: past, present and future events are all on an equal footing. A gradualist believes in a growing block: he agress with the eternalist about the past and the present but not about the future. A presentist believes that what is present has a special (...) status. My first claim is that the familiar ways of articulating these views result in there being no substantive disagreement at all between the three parties. I then show that if we accept the controversial truthmaking principle, we can articulate a substantive disagreenment. Finally, I apply this way of formulating the debate to related questions such as the open future and determinism, showing that these do not always line up in quite the way one would expect. (shrink)

This essay examines the question of the ontological basis for historical propositions and contrasts the positions of A. N. Whitehead and George Santayana, i.e., presentism vs. eternalism. I argue that Whitehead's presentism is a more satisfactory solution to how propositions refer to the past.

It seems possible to see a star that no longer exists. Yet it also seems right to say that what no longer exists cannot be seen. We therefore face a puzzle, the traditional answer to which involves abandoning naïve realism in favour of a sense datum view. In this article, however, I offer a novel exploration of the puzzle within a naïve realist framework. As will emerge, the best option for naïve realists is to embrace an eternalist view of time, (...) and claim that in the relevant case, one sees a still existent star‐stage located somewhere in the distant past. (shrink)

If you utter sentence (1) ‘Obama was born in 1961’ now, you say something true about the past. Since the past will always be such that the year 1961 has the property of being a time in which Obama was born, it seems impossible that could ever be false in a future context of utterance. We shall consider the case of a sentence about the past exactly like (1), but which was true when uttered a few years (...) ago and is no longer true now. On this basis, we shall conclude that the past has changed. (shrink)

It is often said that, according to common sense, there is a fundamental asymmetry between the past and future; namely, that the past is closed and the future is open. Eternalism in the ontology of time is often seen as conflicting with common sense on this point. Here I argue against the claim that common sense is committed to this fundamental asymmetry between the past and the future, on the grounds that facts about the past (...) often depend on facts about the future.1. (shrink)

This chapter focuses on the ontological nature of the past and our experience of the present in relation to the actual. It is argued that philosophers mistakenly equate the real with the actual. The actual is what is presented to us in experience, but what is presented to us in experience is confined to the present; so one might think that it follows that only the present is real. This presentist theory is subsequently rejected. Past, present and future (...) are real and certain mental acts such as memories of the past and expectations of the future have as their content objects at those times; these objects are just as real as the objects of present experiences. This paves the way for a distinctive brand of eternalism that is defended in the remainder of this chapter. (shrink)

Presentism says that only present objects exist. But the view has trouble grounding past-tensed truths like “dinosaurs existed”. Standard Eternalism grounds those truths by positing the existence of past objects—like dinosaurs. But Standard Eternalism conflicts with the intuition that there is genuine change—the intuition that there once were dinosaurs and no longer are any. I offer a novel theory of time—‘The Imprint’—that does a better job preserving both the grounding and genuine change intuitions. The Imprint says (...) that the past and present exist, but where the present exhibits mass-energy, the past only consists of curved empty regions of spacetime. We therefore avoid saying that there are dinosaurs, since there is no mass-energy in the past; but the curvature of the past gives us a way to ground the truth that “dinosaurs existed”. (shrink)

In The Langoliers, passengers on an airline flight wake to find that they’ve mysteriously travelled a few minutes back in time… a few minutes behind everyone else. They find that the world still exists, after ‘the present’ has moved on, but only for a short duration before the Langoliers—the timekeepers of eternity—arrive to remove it permanently from existence. This story prompts two interesting questions: How should we understand the nature of time in The Langoliers? Could the nature of time in (...) our world be the same as in The Langoliers? And, are the characters in The Langoliers really time travellers? In answering these questions, we can gain a greater understanding of the world depicted in The Langoliers, as well as of our own world. (shrink)

This paper investigates ‘exterminous hypertime’, a model of time travel in which time travellers can change the past in virtue of there being two dimensions of time. This paper has three parts. Part one discusses the laws which might govern the connection between different ‘hypertimes’, showing that there are no problems with overdetermination. Part two examines a set of laws that mean changes to history take a period of hypertime to propagate through to the present. Those laws are of (...) interest because: (i) at such worlds, a particular problem for non-Ludovician time travel (‘the multiple time travellers’ problem) is avoided; and (ii) they allow us to make sense of certain fictional narratives. Part three discusses how to understand expectations and rational decision making in a world with two dimensions of time. I end with an appendix discussing how the different theories in the metaphysics of time (e.g., tensed/tenseless theories and presentism/eternalism/growing block theory) marry up with exterminous hypertime. (shrink)

Presentism is usually understood as the thesis that only the present exists whereas the rival theory of eternalism is usually understood as the thesis that past, present, and future things are all equally real. The significance of this debate has been threatened by the so-called triviality objection, which allegedly shows that the presentist thesis is either trivially true or obviously false: Presentism is trivially true if it is read as saying that everything that exists now is present, and (...) it is obviously false if read as saying that everything that has existed, exits or will exist is present. If eternalism is taken as the negation of presentism, it is also either trivially false or obviously true. In this paper, I try to respond to the triviality objection on behalf of presentism. In second section, I will examine how the argument proceeds. In third section, I will reflect on three possible ways to respond but will argue that none of them succeeds in giving a satisfactory solution. I will then try to clarify the core idea of presentism and to suggest that if we characterise presentism accurately, the problem will disappear. In fourth section, I will offer a plausible definition of presentism and will show how it can avoid the triviality objection and demonstrate why it is advantageous to accept the version of presentism I offer. (shrink)

Eternalists believe that there is no ontological difference between the past, present and future. Thus, a challenge arises: in virtue of what does time have a direction? Some eternalists, Oaklander and Tegtmeier ) argue that the direction of time is primitive. A natural response to positing primitive directionality is the suspicion that said posit is too mysterious to do any explanatory work. The aim of this paper is to relieve primitive directionality of some of its mystery by offering a (...) novel way to understand the phenomenon in terms of the recently popularised notion of grounding. (shrink)

Temporal ontology is the philosophical debate on the existence of the past and the future. It features a three-way confrontation between supporters of presentism (the present exists, the past and the future do not), pastism (the past and the present exist, the future does not), and eternalism (the past, the present, and the future all exist). Most philosophers engaged in this debate believe that presentism is much more in agreement with common sense than the rival (...) views; moreover, most of them believe that being in agreement with common sense is epistemically valuable for a philosophical view. We studied experimentally non-experts’ ideas pertaining to the domain of temporal ontology, i.e., as we called it, common-sense temporal ontology, focusing on the Italian population. We found that a non-overwhelming majority of participants (~64%) favoured presentism, while two significant minorities favoured pastism (~19%) and eternalism (~17%). We think that our findings provide some support, albeit weaker than expected, for the view that presentism is more in agreement with common sense than the rival positions. (shrink)

This paper brings two fresh perspectives on Lewis’s theory of time travel. First: many key aspects and theoretical desiderata of Lewis’s theory can be captured in a framework that does not commit to eternalism about time. Second: implementing aspects of Lewisian time travel in a non-eternalist framework provides theoretical resources for a better treatment of time travel to the future. While time travel to the past has been extensively analyzed, time travel to the future has been comparatively underexplored. (...) I make progress on this topic. Along the way, I discuss Lewis’s lesser-known time travel oeuvre, especially his volume of correspondence and lectures on the topic collected in Beebee and Fisher (2020) and Janssen-Lauret & MacBride (forthcoming). Lewis’s body of unpublished work on time travel yields fruitful insights into his broader thinking on the subject. (shrink)

The book is divided into three parts. The first, containing three papers, focuses on the characterization of the central tenets of previii sentism (by Neil McKinnon) and eternalism (by Samuel Baron and Kristie Miller), and on the ‘sceptical stance’ (by Ulrich Meyer), a view to the effect that there is no substantial difference between presentism and eternalism. The second and main section of the book contains three pairs of papers that bring the main problems with presentism to the (...) fore and outlines its defence strategy. Each pair of papers in this section can be read as a discussion between presentists and eternalists, wherein each directly responds to the arguments and objections offered by the other. This is a discussion that is sometimes absent in the literature, or which is at best carried out in a fragmented way. The first two papers of the section deal with the problem of the compatibility of Special Relativity Theory (SRT) and presentism. SRT is often considered to be a theory that contradicts the main tenet of presentism, thereby rendering presentism at odds with one of our most solid scientific theories. Christian Wüthrich’s paper presents arguments for the incompatibility of the two theories (SRT and presentism) within a new framework that includes a discussion of further complications arising from the theory of Qauantum Mechanics. Jonathan Lowe’s paper, by contrast, develops new general arguments against the incompatibility thesis and replies to Wüthrich’s paper. The second pair of papers focuses on the problem that presentists face, in providing grounds for past tensed truths. In the first (by Matthew Davidson), new arguments are provided to defend the idea that the presentist cannot adequately explain how what is now true about the past is grounded, since for the presentist the past is completely devoid of ontological ground. The second paper (by Brian Kierland) takes up the challenge of developing a presentist explanation of past truths, beginning by outlining some existing views in the literature before advancing an original proposal. (shrink)

This paper shows that several live philosophical and scientific hypotheses – including the holographic principle and multiverse theory in quantum physics, and eternalism and mind-body dualism in philosophy – jointly imply an audacious new theory of free will. This new theory, "Libertarian Compatibilism", holds that the physical world is an eternally existing array of two-dimensional information – a vast number of possible pasts, presents, and futures – and the mind a nonphysical entity or set of properties that "read" that (...) physical information off to subjective conscious awareness (in much the same way that a song written on an ordinary compact-disc is only played when read by an outside medium, i.e. a CD-player). According to this theory, every possible physical “timeline” in the multiverse may be fully physically deterministic or physically-causally closed but each person’s consciousness still entirely free to choose, ex nihilo, outside of the physical order, which physically-closed timeline is experienced by conscious observers. Although Libertarian Compatibilism is admittedly fantastic, I show that it not only follows from several live scientific and philosophical hypotheses, I also show that it (A) is a far more explanatorily powerful model of quantum mechanics than more traditional interpretations (e.g. the Copenhagen, Everett, and Bohmian interpretations), (B) makes determinate, testable empirical predictions in quantum theory, and finally, (C) predicts and explains the very existence of a number of philosophical debates and positions in the philosophy of mind, time, personal identity, and free will. First, I show that whereas traditional interpretations of quantum mechanics are all philosophically problematic and roughly as ontologically “extravagant” as Libertarian Compatibilism – in that they all posit “unseen” processes – Libertarian Compatibilism is nearly identical in structure to the only working simulation that human beings have ever constructed capable of reproducing (and so explaining) every general feature of quantum mechanics we perceive: namely, massive-multiplayer-online-roleplaying videogames (or MMORPGs). Although I am not the first to suggest that our world is akin to a computer simulation, I show that existing MMORPGs (online simulations we have already created) actually reproduce every general feature of quantum mechanics within their simulated-world reference-frames. Second, I show that existing MMORPGs also replicate (and so explain) many philosophical problems we face in the philosophy of mind, time, personal identity, and free will – all while conforming to the Libertarian Compatibilist model of reality. -/- I conclude, as such, that as fantastic and metaphysically extravagant as Libertarian Compatibilism may initially seem, it may well be true. It explains a number of features of our reality that no other physical or metaphysical theory does. (shrink)

I argue that, for all we know, there are perfectly ordinary actual entities that are temporal in the usual sense and yet never present, past, or future. This epistemic fact requires us to modify the theses of presentism and eternalism. More importantly, it generates three new and quite serious objections to presentism, which I formulate and partially evaluate in this paper.

Truthmaking is the metaphysical exploration of the idea that what is true depends upon what exists. Truthmaker theorists argue about what the truthmaking relation involves, which truths require truthmakers, and what those truthmakers are. This Element covers the dominant views on these core issues in truthmaking. It also explores some key metaphysical topics and debates that are usefully approached by employing the tools of truthmaker theory: the debate between presentists and eternalists over the existence of entities from the past, (...) and the debate between actualists and possibilists over merely possible states of affairs. In the final section, the Element explores how to think about truthmakers for truths involving social constructions. (shrink)

This chapter introduces time travel into the Star Wars lore. Time travel stories in which the past is changed are in danger of being inconsistent or plagued by paradoxes. In famous time travel stories such as Back to the Future, the protagonist travels to the past, changes the past, and then returns to a present quite different from the one they left. In contemporary philosophy of time, there are three main approaches to this question: presentism, eternalism, (...) and the growing block universe. Time travel works by entering a place, the World Between Worlds, that connects different points in time and space. In terms of modern physics, the portals in the World Between Worlds may be understood as traversable wormholes. The nature of time and the possibility of time travel have attracted and captivated humanity for centuries. (shrink)

Opponents of presentism have often argued that the presentist has difficulty in accounting for what makes true past-tensed propositions true in a way that is compatible with her metaphysical view of time and reality. The problem is quite general and concerns not only strong truth-maker principles, but also the requirement that truth be grounded in reality. In order to meet the challenge, presentists have proposed many peculiar present aspects of the world as grounds for truths concerning the past, (...) such as uninstantiated haecceities, Meinongian non-existents, ersatz times, and dispositional and distributional properties. The main problem with all such solutions is that any explanation of what grounds a TptP that involves the past is eo ipso a better explanation than any that involves only the present. Thus, the quest for an account of grounding for TptP that is compatible with the presentist ontology and ideology is doomed to be explanatorily deficient with respect to eternalism. In a recent article, Ben Caplan and David Sanson have claimed that presentists should change their strategy and, rather than seeking for exotic grounds for TptP, should adopt a more liberal view of explanation. That is, they should allow themselves to resort to “past directed” explanations, even if they do not accept the past in their ontology and ideology. I argue that such a proposal is not compatible with the tenet that there is a substantial distinction between the ideology of such a version of presentism and that of eternalism. Therefore, the presentist cannot endorse such “deflationist” explanations as an easy way out to the problem of the grounding of TptP. (shrink)

In this dialogue I discuss the connection between eternalism and fatalism. I do not think, as some do, that eternalism implies fatalism, but I do think that eternalists can avoid fatalism only by denying a seemingly intuitive claim about what a traveller to the past cannot do.Export citation.

This article argues that the possibility that we live in a computer simulation has important implications for the philosophy of time and time travel. Section 2 distinguishes real time from simulated time. Section 3 argues that whatever is true of real time, simulated time realises a functional analogue within real time to versions of presentism in which features of the present play the role of an uninstantiated past and future. Section 4 then argues that whereas real time travel paradoxes (...) depend upon the ultimate nature of ‘base-reality’ and consistency with observed physics, the possibility of simulated time travel depends instead on a simulation's code, which may allow seemingly ‘miraculous’ exceptions to ‘physical laws’. Finally, Section 5 concludes that if miraculous forms of time travel are discovered, this may provide evidence by inference to the best explanation that we live in a simulation. (shrink)

This paper argues for a certain kind of anti‐metaphysicalism about the temporal ontology debate, i.e., the debate between presentists and eternalists over the existence of past and future objects. Three different kinds of anti‐metaphysicalism are defined—namely, non‐factualism, physical‐empiricism, and trivialism. The paper argues for the disjunction of these three views. It is then argued that trivialism is false, so that either non‐factualism or physical‐empiricism is true. Finally, the paper ends with a discussion of whether we should endorse non‐factualism or (...) physical‐empiricism. An initial reason is provided for thinking that non‐factualism might be true, but in the end, the paper leaves this question open. The paper also argues against a certain kind of necessitarianism about the temporal ontology debate; but this isn't an extra job—the falsity of this necessitarian view falls out of the other arguments as a sort of corollary. (shrink)

In his paper “Aquinas, Geach, and Existence”, D. Costa maintains that Aquinas’ solution to the puzzle of future contingent events entails that future contingent entities already exist. This is tantamount to state that Aquinas endorsed a form of eternalism, since he maintained that past, present and future timelessly exist in God’s sight. I object that Aquinas’ texts are also compatible with another reading. In any statement of the form “S will be P”, the verb “will be” simply states (...) the truth of the predicative link between S and P, not the existence of either S or P. In other words, I take the verb “to be” occurring in sentences describing future events as having the meaning of the “esse ut verum”. (shrink)

Gödel's Philosophical Legacy Kurt Gödel's contributions to philosophy extend beyond his incompleteness theorems. He engaged deeply with the work of other philosophers, including Immanuel Kant and Edmund Husserl, and explored topics such as the nature of time, the structure of the universe, and the relationship between mathematics and reality. Gödel's philosophical writings, though less well-known than his mathematical work, offer rich insights into his views on the nature of existence, the limits of human knowledge, and the interplay between the finite (...) and the infinite. His work continues to inspire and challenge philosophers, mathematicians, and scientists, inviting them to explore the profound and often enigmatic questions at the heart of human understanding. -/- Kurt Gödel's Broader Contributions to Philosophy Kurt Gödel, while primarily known for his monumental incompleteness theorems, made significant contributions that extended beyond the realm of mathematical logic. His philosophical pursuits deeply engaged with the works of eminent philosophers like Immanuel Kant and Edmund Husserl. Gödel's explorations into the nature of time, the structure of the universe, and the relationship between mathematics and reality reveal a profound and multifaceted intellectual legacy. -/- Engagement with Immanuel Kant Gödel held a deep interest in the philosophy of Immanuel Kant. He admired Kant's critical philosophy, particularly the distinction between the noumenal and phenomenal worlds. Kant posited that human experience is shaped by the mind’s inherent structures, leading to the conclusion that certain aspects of reality (the noumenal world) are fundamentally unknowable. Gödel’s incompleteness theorems echoed this Kantian theme, illustrating the limits of formal systems in capturing the totality of mathematical truth. Gödel believed that mathematical truths exis t independently of human thought, akin to Kant's noumenal realm. This philosophical alignment provided a robust foundation for Gödel's Platonism, which asserted the existence of mathematical objects as real, albeit abstract, entities. -/- Influence of Edmund Husserl Gödel was also profoundly influenced by Edmund Husserl, the founder of phenomenology. Husserl's phenomenology emphasizes the direct investigation and description of phenomena as consciously experienced, without preconceived theories about their causal explanation. Gödel saw Husserl's work as a pathway to bridge the gap between the abstract world of mathematics and concrete human experience. Husserl's ideas about the structures of consciousness and the intentionality of thought resonated with Gödel's views on mathematical intuition. Gödel believed that human minds could access mathematical truths through intuition, a concept that draws on Husserlian phenomenological methods. -/- The Nature of Time and the Universe Gödel's philosophical inquiries extended to the nature of time and the structure of the universe. His collaboration with Albert Einstein at the Institute for Advanced Study led to the development of the "Gödel metric" in 1949. This solution to Einstein's field equations of general relativity described a rotating universe where time travel to the past was theoretically possible. Gödel's model challenged conventional notions of time and causality, suggesting that the universe might have a more intricate structure than previously thought. Gödel's exploration of time was not just a mathematical curiosity but a profound philosophical statement about the nature of reality. He questioned whether time was an objective feature of the universe or a construct of human consciousness. His work hinted at a timeless realm of mathematical truths, aligning with his Platonist view. -/- Mathematics and Reality Gödel's philosophical outlook extended to the broader relationship between mathematics and reality. He believed that mathematics provided a more profound insight into the nature of reality than empirical science. For Gödel, mathematical truths were timeless and unchangeable, existing independently of human cognition. This perspective led Gödel to critique the materialist and mechanistic views that dominated 20th-century science and philosophy. He argued that a purely physicalist interpretation of the universe failed to account for the existence of abstract mathematical objects and the human capacity to understand them. Gödel's philosophy suggested a more integrated view of reality, where both physical and abstract realms coexist and inform each other. -/- Gödel's Exploration of Time Kurt Gödel, one of the most profound logicians of the 20th century, ventured beyond the confines of mathematical logic to explore the nature of time. His inquiries into the concept of time were not merely theoretical musings but were grounded in rigorous mathematical formulations. Gödel's exploration of time challenged conventional views and opened new avenues of thought in both physics and philosophy. -/- Gödel and Einstein Gödel’s interest in the nature of time was significantly influenced by his friendship with Albert Einstein. Both were faculty members at the Institute for Advanced Study in Princeton, where they engaged in deep discussions about the nature of reality, time, and space. Gödel's exploration of time culminated in his solution to Einstein's field equations of general relativity, known as the Gödel metric. -/- The Gödel Metric In 1949, Gödel presented a model of a rotating universe, which became known as the Gödel metric. This solution to the equations of general relativity depicted a universe where time travel to the past was theoretically possible. Gödel’s rotating universe contained closed timelike curves (CTCs), paths in spacetime that loop back on themselves, allowing for the possibility of traveling back in time. The Gödel metric posed a significant philosophical challenge to the conventional understanding of time. If time travel were possible, it would imply that time is not linear and absolute, as commonly perceived, but rather malleable and subject to the geometry of spacetime. This raised profound questions about causality, the nature of temporal succession, and the very structure of reality. -/- Philosophical Implications Gödel’s exploration of time extended beyond the mathematical implications to broader philosophical inquiries: Nature of Time: Gödel questioned whether time was an objective feature of the universe or a construct of human consciousness. His work suggested that our understanding of time as a linear progression from past to present to future might be an illusion, shaped by the limitations of human perception. -/- Causality and Free Will: The existence of closed timelike curves in Gödel’s model raised questions about causality and free will. If one could travel back in time, it would imply that future events could influence the past, potentially leading to paradoxes and challenging the notion of a deterministic universe. -/- Temporal Ontology: Gödel's work contributed to debates in temporal ontology, particularly the debate between presentism (the view that only the present exists) and eternalism (the view that past, present, and future all equally exist). Gödel’s rotating universe model seemed to support eternalism, suggesting a block universe where all points in time are equally real. Philosophy of Science: Gödel’s exploration of time had implications for the philosophy of science, particularly in the context of understanding the limits of scientific theories. His work underscored the importance of considering philosophical questions when developing scientific theories, as they shape our fundamental understanding of concepts like time and space. -/- Legacy Gödel’s exploration of time remains a significant and controversial contribution to both physics and philosophy. His work challenged established notions and encouraged deeper inquiries into the nature of reality. Gödel’s rotating universe model continues to be a topic of interest in theoretical physics and cosmology, inspiring new research into the nature of time and the possibility of time travel. In philosophy, Gödel’s inquiries into time have prompted ongoing debates about the nature of temporal reality, the relationship between mathematics and physical phenomena, and the limits of human understanding. His work exemplifies the intersection of mathematical rigor and philosophical inquiry, demonstrating the profound insights that can emerge from such an interdisciplinary approach. The Temporal Ontology of Kurt Gödel Kurt Gödel's profound contributions to mathematics and logic extend into the realm of temporal ontology—the philosophical study of the nature of time and its properties. Gödel's insights challenge conventional perceptions of time and suggest a more intricate, layered understanding of temporal reality. This essay explores Gödel's contributions to temporal ontology, particularly through his engagement with relativity and his philosophical reflections. -/- Gödel's Rotating Universe One of Gödel’s most notable contributions to temporal ontology comes from his work in cosmology, specifically his solution to Einstein’s field equations of general relativity, known as the Gödel metric. Introduced in 1949, the Gödel metric describes a rotating universe with closed timelike curves (CTCs). These curves imply that, in such a universe, time travel to the past is theoretically possible, presenting a significant challenge to conventional views of linear, unidirectional time. -/- Implica tions for Temporal Ontology Gödel's rotating universe model has profound implications for our understanding of time: Eternalism vs. Presentism: Gödel’s model supports the philosophical stance known as eternalism, which posits that past, present, and future events are equally real. In contrast to presentism, which holds that only the present moment exists, eternalism suggests a "block universe" where time is another dimension like space. Gödel’s rotating universe, with its CTCs, reinforces this view by demonstrating that all points in time could, in principle, be interconnected in a consistent manner. Non-linearity of Time: The possibility of closed timelike curves challenges the idea of time as a linear sequence of events. In Gödel’s universe, time is not merely a straight path from past to future but can loop back on itself, allowing for complex interactions between different temporal moments. This non-linearity has implications for our understanding of causality and the nature of temporal succession. Objective vs. Subjective Time: Gödel’s work invites reflection on the distinction between objective time (the time that exists independently of human perception) and subjective time (the time as experienced by individuals). His model suggests that our subjective experience of a linear flow of time may not correspond to the objective structure of the universe. This raises questions about the relationship between human consciousness and the underlying temporal reality. -/- Gödel and Philosophical Reflections on Time Gödel’s engagement with temporal ontology was not limited to his cosmological work. He also reflected deeply on philosophical questions about the nature of time and reality, drawing on the ideas of other philosophers and integrating them into his own thinking. Kantian Influences: Gödel was influenced by Immanuel Kant’s distinction between the noumenal world (things as they are in themselves) and the phenomenal world (things as they appear to human observers). Gödel’s views on time echoed this distinction, suggesting that our perception of time might be a phenomenon shaped by the limitations of human cognition, while the true nature of time (the noumenal aspect) might be far more complex and non-linear. Husserlian Phenomenology: Gödel’s interest in Edmund Husserl’s phenomenology also informed his views on time. Husserl’s emphasis on the structures of consciousness and the intentionality of thought resonated with Gödel’s belief in the importance of intuition in accessing mathematical truths. Gödel’s reflections on time incorporated a phenomenological perspective, considering how temporal experience is structured by human consciousness. Mathematical Platonism: Gödel’s Platonist views extended to his understanding of time. Just as he believed in the independent existence of mathematical objects, Gödel saw time as an objective entity with a structure that transcends human perception. His work on the Gödel metric can be seen as an attempt to uncover this objective structure, revealing the deeper realities that underlie our experience of time. (shrink)

There are several faces of Four-Dimensionalism. Sometimes 4D-ism is formulated as the thesis that the material world is composed of spatial as well as temporal parts. Another version of 4D-ism states that persisting objects are extended over time in the same way that they are extended over space. Some Four-Dimensionalists defend the thesis that all objects persist by perduring i.e. by having different temporal parts at different times. Sometimes 4D-ism means the same as eternalism - the thesis that (...) class='Hi'>past and future objects (and times) are just as real as currently existing ones. Finally it can mean the thesis that all objects are in fact four-dimensional i.e. they are in every case a filling of some subregions of space-time. The author examines some varieties of 4D-ism and tries to formulate both a precise meaning of those doctrines and an evaluation of them. (shrink)

There are several faces of Four-Dimensionalism (4D). Sometimes 4D is formulated as the thesis that the material world is composed of spatial as well as temporal parts. Another version of 4D states that persisting objects are extended over time in the same way that they are extended over space. Some Four-Dimensionalists defend the thesis that all objects persist by perduring i.e. by having different temporal parts at different times. Sometimes 4D means the same as eternalism - the thesis that (...) past and future objects (and times) are just as real as currently existing ones. Finally it can mean the thesis that all objects are in fact four-dimensional i.e. they are in every case a filling of some subregions of space-time. The author examines some varieties of 4D and tries to formulate both a precise meaning of those doctrines and an evaluation of them. (shrink)

What do “existing” and “having existed” mean? The answer to this question depends radically on the metaphysical assumption that we are making about the nature of time. If we take the present to be privileged over other times, then “having existed” is bound to express a notion close to non-existence. If we think that the present has no ontological supremacy over what was and what will be, then the difference between “having existed” and “existing” is bound to be no deeper (...) than the difference between “existing here” and “existing there”. In this article I show that the view to the effect that the present is privileged, i.e. “presentism”, suffers from a fatal problem concerning the present truth of many past-tensed existential statements. Therefore, we had better abandon it in favour of “eternalism” – the rival view to the effect that between “existing” and “having existed” there is no ontological difference. (shrink)

It is tempting to understand Hegel as a philosopher belonging to the tradition which began with the pre-Socratics, was set in its path definitively by Plato, and culminated with Hegel himself. Hegel’s place in that tradition cannot be denied, but it must be qualified; for with this understanding goes a claim that Hegel conceived of himself as the philosopher at “the end of history.” Hegel is understood to have articulated a system of philosophy which gave us the truth for all (...) time, future as well as past. Time is annulled, cancelled, negated and, at least in philosophy, we are faced with eternity. This interpretation of Hegel, however, leaves us with too many problems. In general, it must either ignore or deny the radically temporal aspects of Hegel, relegating them to “a young Hegel,” either identifying time and eternity or simply denying the essentiality of time for Hegel. All of these strategies, and the eternalist interpretation which necessitates them, must be rejected as onesided; for the interpretation leaves unaddressed Hegel’s rejection, in his “mature” years, of such an eternalism. Furthermore, the interpretation is based upon an unexamined presupposition that if we are going to have metaphysics, then we must have a system which either transcends or absorbs history and time. This was not a presupposition shared by Hegel, at least not in its usual sense. (shrink)

The causal set programme towards a quantum theory of gravity is situated vis-à-vis the long-standing debate between eternalism (block theory) and past-presentism or possibilism (growing block theory) in the philosophy of time. It is argued that despite 'appearances' and declarations to the contrary, the programme does not side with growing block theorists when it comes to harboring a robust notion of Becoming - at least, not more than familiar relativistic theories on continuous spacetime manifolds. The problem stems mainly (...) from the postulate of discrete general covariance - a requirement imposed upon the only fully worked out kind of dynamics for causal sets to date, a dynamics of a classical stochastic process. (shrink)

In this paper, we articulate a version of non-standard A-theory—which we call Flow Fragmentalism—in relation to its take on the issue of supervenience of truth on being. According to the Truth Supervenes on Being (TSB) Principle, the truth of past- and future-tensed propositions supervenes, respectively, on past and future facts. Since the standard presentist denies the existence of past and future entities and facts concerning them that do not obtain in the present, she seems to lack the (...) resources to accept both past and future-tensed truths and the TSB Principle. Contrariwise, positions in philosophy of time that accept an eternalist ontology (e.g., B-theory, moving spotlight, and Fine’s and Lipman’s versions of fragmentalism) allow for a “direct” supervenience base for past- and future-tensed truths. We argue that Flow Fragmentalism constitutes a middle ground, which retains most of the advantages of both views, and allows us to articulate a novel account of the passage of time. (shrink)

Many philosophers believe there to be a fundamental difference between the present and past and future times, but they tend to disagree amongst themselves about what this difference is. Some think that the present is singled out by consciousness, while others believe that it marks the position to which the flow of time has advanced. According to presentism, the current moment is ontologically privileged: nothing exists that is not present. My aim in this chapter is to argue that this (...) particular attempt at distinguishing the present from other times is unsuccessful. (shrink)

The paper has two parts: First, I describe a relatively popular thesis in the philosophy of propositional attitudes, worthy of the name ‘taking tense seriously’; and I distinguish it from a family of views in the metaphysics of time, namely, the A-theories (or what are sometimes called ‘tensed theories of time’). Once the distinction is in focus, a skeptical worry arises. Some A-theorists maintain that the difference between past, present, and future, is to be drawn in terms of what (...) exists: growing-block theorists eschew ontological commitment to future entities; presentists, to future and past entities. Others think of themselves as A-theorists but exclude no past or future things from their ontology. The metaphysical skeptic suspects that their attempt to articulate an ‘eternalist’ version of the A-theory collapses into merely ‘taking tense seriously’– a thesis that does not imply the A-theory. The second half of the paper is the search for a stable eternalist A-theory. It includes discussion of temporary intrinsics, temporal parts, and truth. (shrink)