Suppose nothing exists. Then it is true that nothing exists. What makes that true? Nothing! So it seems that if nothing existed, then the principle that every truth is made true by something (the truthmaker principle) would be false. So if it is possible that nothing exists, a claim often called 'metaphysical nihilism', then the truthmaker principle is not necessary. This paper explores various ways to resolve this conflict without restricting metaphysical nihilism in such a way that it would become (...) trivial and uninteresting. (shrink)

This paper investigates the prospects of developing a branching modal framework while keeping with the spirit of Humean Supervenience. It is argued that such an approach is bound to face hard problems regarding haecceitism and the notion of recombination. Possible directions for future philosophical developments of branching frameworks are suggested.

Modal primitivists hold that some modal truths are primitively true. They thus seem to face a special epistemological problem: how can primitive modal truths be known? The epistemological objection has not been adequately developed in the literature. I undertake to develop the objection, and then to argue that the best formulation of the epistemological objection targets all realists about modality, rather than the primitivist alone. Furthermore, the moves available to reductionists in response to the objection are also available to primitivists. (...) I conclude by suggesting that extant theories of the epistemology of modality are not sensitive to the question of primitivism versus reductionism. (shrink)

Many are reluctant to accept primitive modality into their fundamental picture of the world. The worry often traces to this thought: we shouldn't adopt any more primitive - that is, unexplained - notions than we need in order to explain all the features of the world, and primitive modal notions are not needed. I examine one prominent rival to modal primitivism, combinatorialism, and show that in order to account for all the modal features of the world the combinatorialist must adopt (...) two additional primitive notions. My own modal primitivist view takes as primitive the notion of incompatibility between properties or relations. I show how the non-modal notions that the combinatorialist must adopt as primitive may be analyzed using my notion. The upshot is that with respect to the number of primitive notions, my modal primitivist theory comes out ahead. (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)

I suggest a way in which metaphysics might cure us of our desire for immortality. Supposing that time is composed of instants, or even that time could be composed of instants, leads to the conclusion that there is nothing good that immortality offers, nothing we might reasonably want, that is in principle unavailable to a mere mortal. My argument proceeds in three stages. First, I suggest a necessary condition for a feature to ground the desirability of a life or a (...) portion thereof. Second, after distinguishing between three different features that could plausibly be meant by ’immortality’, I argue that if time could be composed of instants, only one of those features satisfies the necessary condition, and it evidently fails to ground the desirability of a life. Third, I argue that no feature that entails any of the three features grounds the desirability of a life either. I conclude with reflections on what this means for our longing for immortality. (shrink)

Classic inductive skepticism–the epistemological claim that we have no good reason to believe that the unobserved resembles the observed–is plausibly everyone’s lot, whether or not they embrace Hume’s metaphysical claim that distinct existents are “entirely loose and separate”. But contemporary advocates of a Humean metaphysic accept a metaphysical claim stronger than Hume’s own. I argue that their view plausibly gives rise to a radical inductive skepticism–according to which we are downright irrational in believing as we do about the unobserved–that we (...) don’t otherwise have reason to accept. The Metaphysical Neo-Humean is in an epistemological quagmire all her own. (shrink)

David Lewis claims that his theory of modality successfully reduces modal items to nonmodal items. This essay will clarify this claim and argue that it is true. This is largely an exercise within ‘Ludovician Polycosmology’: I hope to show that a certain intuitive resistance to the reduction and a set of related objections misunderstand the nature of the Ludovician project. But these results are of broad interest since they show that would-be reductionists have more formidable argumentative resources than is often (...) thought. Lewis’s reduction depends on a set of methodological commitments each of which is fairly plausible or at least currently popular, and none of which is particular to modality. The choice of which of these commitments to reject I leave to the discerning antireductionist. The essay proceeds as follows: §1 discusses reduction generally and one or two relevant puzzles; §2 discusses Lewis’s reduction in particular; the longest section, §3 replies to four objections. (shrink)

Structuralism and quidditism are competing views of the metaphysics of property individuation: structuralists claim that properties are individuated by their nomological roles; quidditists claim that they are individuated by something else. This paper (1) refutes what many see as the best reason to accept structuralism over quidditism and (2) offers a methodological argument in favor of a quidditism. The standard charge against quidditism is that it commits us to something ontologically otiose: intrinsic aspects of properties, so-called ‘quiddities’. Here I grant (...) that quiddities are ontologically otiose, but deny that quidditism requires them. According to a view I call ‘austere quidditism’, properties are individuated by bare numerical identity. I argue that, as far as ontological parsimony is concerned, austere quidditism and structuralism are on a par. But is austere quidditism a coherent alternative to structuralism? To see that it is, we must get clear on what exactly we mean by ‘property individuation’. What we discover is that structuralism is a counterpart theory for properties, and that austere quidditism is simply the rejection of counterpart theory. I conclude with a methodological argument to the effect that counterpart theory for properties ought to be rejected. This paper begins by situating the debate between structuralists and quidditists within the context of a debate over the epistemic limits of fundamental science. At the center of this debate is David Lewis’s posthumously published ‘Ramseyan Humility’ (2008). In the appendix I explain the precise role of austere quidditism in Lewis’s argument. (shrink)

The paper is a survey of contemporary quidditism, understood as two interrelated metaphysicalpositions — recombinatorial quidditism, which is an account of the nature of possibilities, andindividuation quidditism, which is concerned with the problem of how to individuate properties.I have three aims: to examine the commitments and consequences of both views, to investigatethe relationships between them, and to sketch the logic of the dispute between structuralism andquidditism. I explain how these views relate to Ramseyan humility, according to which we cannotknow the (...) fundamental structure of the world. (shrink)

In this paper, I discuss a connection between quidditism and the Lewisian principle of recombination. I begin by reconstructing a typical characterisation of a Lewisian principle of recombination, followed by an explanation of quidditism. In the remainder, I argue that a proponent of a Lewisian principle of recombination cannot endorse quidditism without some important modifications of her view.

This article sits at a point of intersection between the philosophy of physics and the metaphysics of modality. There are clear similarities between Everettian quantum mechanics and various modal metaphysical theories, but there have hitherto been few attempts at exploring how the two topics relate. In this article, I build on a series of recent papers by Wilson ([2011], [2012], [2013]), who argues that Everettian quantum mechanics’ connections with traditional modal metaphysics are vital in defending it against objections. I show (...) that Wilson’s preferred version of Everettian quantum mechanics has two problems. First, it is unable to account for the contingency of various intuitively contingent modal claims. Second, it fails to yield intuitive truth values on modal claims about the number of branches in a given Everettian multiverse. Since modal claims about branch number are instrumental in decision-theoretic solutions to Everettian quantum mechanics’ problem(s) with probability, this second problem has wider dialectical implications. I suggest amendments to the underlying metaphysics that overcome these problems. The result is a more robust version of Everettian quantum mechanics. (shrink)

According to Lewis's modal realism, all ways the world could be are represented by possible worlds, and all possible worlds represent some way the world could be. That there are just the right possible worlds to represent all and only the ways the world could be is to be guaranteed by the principle of recombination. Lewis sketches the principle , but does not spell out a precise version that generates just the right possibilities. David Efird and Tom Stoneham have offered (...) a principle that aims to do just that.In this paper, we argue that Efird's and Stoneham's principle of recombination is not successful – it fails to generate the right possibilities – but we also suggest ways that their account might be improved to solve the problem we raise. We also argue against Efird's and Stoneham's claim that the correct principle of recombination demonstrates the possibility of nothing concrete – it is true that their principle of recombination has models consistent with the existence of an empty world, but we only get the possibility of nothing if mereologically null individuals are possible. The Lewisian should only think mereologically null individuals are possible if he or she has some independent reason for believing in the possibility of an empty world, so the principle of recombination provides no new evidence for that possibility. We draw some morals from this for the correct way to formulate the principle of recombination. (shrink)

This article discusses the possibility of some outlandish tropes from time travel fiction, such as people reversing in age as they time travel or the universe being destroyed because a time traveler kills their ancestor. First, I discuss what type of possibility we might have in mind, detailing ‘close possibility’ as one such candidate. Secondly, I argue that—with only little exception—these more outlandish tropes fail to be closely possible. Thirdly, I discuss whether these outlandish tropes may nevertheless be more broadly (...) possible (e.g., metaphysically or logically possible), arguing that whether they are or not depends upon your favored metaphysics of the laws of nature. (shrink)

In section 1 I motivate and execute the presentation of a well-defined Lewisian conception of analysis and of what it would be to analyse modality successfully. That conception is then put to two applications. In section 2 various inadequacies are exposed in a (recently popular) separatist approach to the understanding and/or evaluation of Lewis's analysis of modality. Section 3 provides a defence against a resilient argument for the claim that Lewis's analysis of modality cannot be fully reductive while also dealing (...) adequately with alien possibility. (shrink)

According to Lewis's modal realism, all ways the world could be are represented by possible worlds, and all possible worlds represent some way the world could be. That there are just the right possible worlds to represent all and only the ways the world could be is to be guaranteed by the principle of recombination. Lewis sketches the principle (put roughly: anything can co-exist with anything else), but does not spell out a precise version that generates just the right possibilities. (...) David Efird and Tom Stoneham have offered a principle that aims to do just that.In this paper, we argue that Efird's and Stoneham's principle of recombination is not successful – it fails to generate the right possibilities – but we also suggest ways that their account might be improved to solve the problem we raise. We also argue against Efird's and Stoneham's claim that the correct principle of recombination demonstrates the possibility of nothing concrete – it is true that their principle of recombination has models consistent with the existence of an empty world, but we only get the possibility of nothing if mereologically null individuals are possible. The Lewisian should only think mereologically null individuals are possible if he or she has some independent reason for believing in the possibility of an empty world, so the principle of recombination provides no new evidence for that possibility. We draw some morals from this for the correct way to formulate the principle of recombination. (shrink)

In ‘Ramseyan Humility’ Lewis presents the Permutation Argument for quidditism. As he presents it the argument is simple enough, but once one digs beneath its surface, and attempts to understand it in strictly Lewisian terms, difficulties arise. The fundamental difficulty is that, as he presents it, the argument only seems to be sound if one rejects views that Lewis explicitly holds. One aim of this paper is to clarify the argument to show that one can make sense of it in (...) strictly Lewisian terms. In so doing I clarify Lewis’s view, clearly lay out the commitments that Lewis has, and define quidditism in strictly Lewisian terms. However, I also have a secondary aim. Lewis accepts that quidditism entails a form of scepticism, that he calls ‘Humility’. However, by an extension of the permutation argument I show that quidditism entails a form of scepticism, that I call ‘Diffidence’, that is far more wide-reaching than Humility. (shrink)

Haecceitism and Hume’s Dictum are each controversial theses about necessity and possibility. According to haecceitism, there are qualitatively indiscernible possible worlds that differ only with respect to which individuals occupy which qualitative roles. According to Hume’s Dictum, there are no necessary connections between distinct entities or, as Humeans sometimes put it, reality admits of “free recombination” so any entities can co-exist or fail to co-exist. This paper introduces a puzzle that results from the combination of haecceitism and Hume’s Dictum. This (...) puzzle revolves around the free recombination of non-qualitative properties like being Socrates. After considering several responses to this puzzle, I defend an ideology-driven solution, which dispenses with non-qualitative properties like being Socrates in favour of primitive theoretical ideology while, at the same time, preserving a commitment to both haecceitism and Hume’s Dictum. (shrink)

Priority monism (hereafter, ‘monism’) is the view that there exists one fundamental entity—the world—and that all other objects that exist (a set of objects typically taken to include tables, chairs, and the whole menagerie of everyday items) are merely derivative. Jonathan Schaffer has defended monism in its current guise, across a range of papers. Each paper looks to add something to the monistic picture of the world. In this paper we argue that monism—as Schaffer describes it—is false. To do so (...) we develop an ‘island universe’ argument against Schaffer's monistic theory. (shrink)

At the start of his discussion of causation, Hume claims to demonstrate that simultaneous causation is absolutely impossible; all causes must precede their effects in time. I argue that considering Hume’s modal theory can reveal two important and previously unaddressed features of this argument. First, his modal metaphysics resolves one of the most pressing extant interpretive issues: how Hume is able to infer from the claim that it is possible for some object to be simultaneously caused to the claim that (...) it is possible for all objects to be simultaneously caused. This step, I argue, is justified by Hume’s theory of relations. Based on an analysis of the representational capacities of the imagination in the Treatise, I develop a modal theory for relations that supports inferences of this kind. Second, his distinction between absolute and natural modality raises a problem that has not yet been identified in the literature. Hume is trying to conclude that something is metaphysically impossible, but one of his premises relies on a mere natural impossibility (that no object can begin to exist uncaused). I argue that this is an intractable problem: Hume cannot get the conclusion he wants because it depends on an equivocation between two strengths of modality. (shrink)

This article includes a basic overview of possible world semantics and a relatively comprehensive overview of three central philosophical conceptions of possible worlds: Concretism (represented chiefly by Lewis), Abstractionism (represented chiefly by Plantinga), and Combinatorialism (represented chiefly by Armstrong).

I examine issues in the philosophy of religion at the intersection of what possibilities there are and what a God, as classically conceived in the theistic philosophical tradition, would be able to do. The discussion is centered around arguing for an incompatibility between theism and two principles about possibility and ability, and exploring what theists should say about these incompatibilities. -/- I argue that theism entails that certain kinds and amounts of evil are impossible. This puts theism in conflict with (...) popular principles of modal recombination. However, theists have plausible explanations for the violations of recombination that they posit, and can suitably amend these principles without giving up their usefulness in accounting for what possibilities there are. -/- I also argue that despite the impossibility of these evils, God is able to bring these evils about. This puts theism in conflict with the principle that no one is able to do the impossible. However, theists can give a plausible account of why God is unique in being able to do the impossible, and have distinctive resources to address the arguments in favor of the idea that no one is able to do the impossible. And by denying this principle, theists are able to resolve several otherwise difficult puzzles, including reconciling conflicts between the divine attributes. (shrink)