In "A Problem in Possible-World Semantics," David Kaplan presented a consistent and intelligible modal principle that cannot be validated by any possible world frame (in the terminology of modal logic, any neighborhood frame). However, Kaplan's problem is tempered by the fact that his principle is stated in a language with propositional quantification, so possible world semantics for the basic modal language without propositional quantifiers is not directly affected, and the fact that on careful inspection his principle does not target the (...) world part of possible world semantics—the atomicity of the algebra of propositions—but rather the idea of propositional quantification over a complete Boolean algebra of propositions. By contrast, in this paper we present a simple and intelligible modal principle, without propositional quantifiers, that cannot be validated by any possible world frame precisely because of their assumption of atomicity (i.e., the principle also cannot be validated by any atomic Boolean algebra expansion). It follows from a theorem of David Lewis that our logic is as simple as possible in terms of modal nesting depth (two). We prove the consistency of the logic using a generalization of possible world semantics known as possibility semantics. We also prove the completeness of the logic (and two other relevant logics) with respect to possibility semantics. Finally, we observe that the logic we identify naturally arises in the study of Peano Arithmetic. (shrink)

This chapter discusses epistemic objections to non-naturalist moral realism. The goal of the chapter is to determine which objections are pressing and which objections can safely be dismissed. The chapter examines five families of objections: (i) one involving necessary conditions on knowledge, (ii) one involving the idea that the causal history of our moral beliefs reflects the significant impact of irrelevant influences, (iii) one relying on the idea that moral truths do not play a role in explaining our moral beliefs, (...) (iv) one involving the claim that if moral realism is true then our moral beliefs are unlikely to be reliable, and (v) one involving the claim that moral realism is incompatible with there being a plausible explanation of our reliability about morality. The overall conclusion of the chapter is that the final objection is by far the most pressing. (shrink)

Disagreement is common: even informed, intelligent, and generally reasonable people often come to different conclusions when confronted with what seems to be the same evidence. Can the competing conclusions be reasonable? If not, what can we reasonably think about the situation? This volume examines the epistemology of disagreement. Philosophical questions about disagreement arise in various areas, notably politics, ethics, aesthetics, and the philosophy of religion: but this will be the first book focusing on the general epistemic issues arising from informed (...) disagreement. Ten leading philosophers offer specially written essays which together will offer a starting-point for future work on this topic. (shrink)

We need to understand the impossible. Francesco Berto and Mark Jago start by considering what the concepts of meaning, information, knowledge, belief, fiction, conditionality, and counterfactual supposition have in common. They are all concepts which divide the world up more finely than logic does. Logically equivalent sentences may carry different meanings and information and may differ in how they're believed. Fictions can be inconsistent yet meaningful. We can suppose impossible things without collapsing into total incoherence. Yet for the leading philosophical (...) theories of meaning, these phenomena are an unfathomable mystery. To understand these concepts, we need a metaphysical, logical, and conceptual grasp of situations that could not possibly exist: Impossible Worlds. This book discusses the metaphysics of impossible worlds and applies the concept to a range of central topics and open issues in logic, semantics, and philosophy. It considers problems in the logic of knowledge, the meaning of alternative logics, models of imagination and mental simulation, the theory of information, truth in fiction, the meaning of conditional statements, and reasoning about the impossible. In all these cases, impossible worlds have an essential role to play. (shrink)

Ontologiset kategoriateoriat pyrkivät vastaamaan metafysiikan klassiseen ongelmaan: kysymykseen siitä, mihin eri kategorioihin oliot eli entiteetit jakaantuvat. Olioilla tarkoitetaan tässä mitä tahansa, joka on olemassa. Olevan kategoriat eli ontologiset kategoriat (lyhyesti kategoriat) ovat alustavasti olioiden hyvin yleisiä lajeja. Jäsenyys olioiden kategoriassa ei niinkään kerro sitä, mitä piirteitä oliolla on, vaan sen olemisen tavan ¬– miten se esimerkiksi on tai voi olla maailman rakenneosa. Esimerkkejä mahdollisista kategorioista ovat konkreettiset partikulaariset yksilöoliot (substanssit), ominaisuudet, relaatiot, prosessit, tapahtumat ja joukot. -/- 1. Mitä ovat ontologiset (...) kategoriateoriat -/- 2. Uusaristoteelinen realismi -/- 3. Russellilainen realismi -/- 4. Universaalikimpputeoriat -/- 5. Nominalismi: substanssi-modus-teoriat -/- 6. Trooppiteoriat -/- 7. Jyrkkä nominalismi -/- 8. Tapahtuma- ja prosessiontologiat -/- 9. Ontologisten kategorioiden tutkimus Suomessa -/- 10. Suositeltavaa jatkolukemista -/- 11. Lähteet . (shrink)

In this thesis I seek to advance our understanding of what intuitions are. I argue that intuitions are experiences of a certain kind. In particular, they are experiences with representational content, and with a certain phenomenal character. -/- In Chapter 1 I identify our target and provide some important reliminaries. Intuitions are mental states, but which ones? Giving examples helps: a person has an intuition when it seems to her that torturing the innocent is wrong, or that if something is (...) red it is coloured. We can also provide an initial characterisation of the state by saying that it has representational content, often causes belief, and appears to justify belief. In addition, there is something it is like to have an intuition: intuition has a certain phenomenal character. -/- Some argue that intuition does not explain anything which cannot be explained by other mental states. One version of this view takes intuition to reduce to belief. In Chapter 2 I argue that this entails that agents are rationally criticisable in situations where we know they are not, and that such views are therefore untenable. A parallel argument shows that the corresponding approach to perception fails. This suggests a similarity in nature: both intuition and perception are experiences. -/- Others take intuition to reduce to a disposition to have a belief. In Chapter 3 I consider a line of argument against such views, find it unsuccessful, and present two new arguments. One is likely to be dialectically ineffective. The other suffers no such weakness: it shows that the proposed reduction fails. As before, the argument also applies to perception, and suggests that intuition and perception are both experiences. -/- In the remainder of the thesis I develop an account of intuition as an experience. I distinguish between content-specific and attitude-specific phenomenology, and argue that intuition lacks the former (Chapter 4), but has the latter (Chapter 5). This allows us to say what intuition is: it is is an experience with representational content and with attitude-specific phenomenology of a certain kind. -/- In Chapter 6 I put this account of intuition to use. When a person has a perceptual or intuitional experience, I argue that simply having the experience is what makes the subject justified in believing what the experience represents. Moreover, what explains that intuition and perception can justify belief in this way is precisely their phenomenal character. (shrink)

The Oxford Handbook of the Philosophy of Consciousness provides the most comprehensive overview of current philosophical research on consciousness. Featuring contributions from some of the most prominent experts in the field, it explores the wide range of types of consciousness there may be, the many psychological phenomena with which consciousness interacts, and the various views concerning the ultimate relationship between consciousness and physical reality. It is an essential and authoritative resource for anyone working in philosophy of mind or interested in (...) states of consciousness. (shrink)

In this chapter I outline some metaphysical views about time, and about persistence, and discuss how they can help us clarify our thinking about life and death.

This dissertation is divided into two parts. In the first part I defend substantivalism. I do this by offering, in chapter 1, a counterpart-theoretic defense of substantivalism from Leibniz’ shift arguments. Then, in chapter 2, I defend substantivalism from the hole argument and argue, against the consensus, that the question of haecceitism is irrelevant to substantivalism in the context of general relativity. In the second part of the dissertation I defend supersubstantivalism. I do this by offering, in chapter 3, an (...) argument against dualistic substantivalism. The argument appeals to plausible principles of modal plenitude to show that the dualist is committed to a range of problematic possibilities. Then, in chapter 4, I consider a range of supersubstantivalist positions. I conclude by arguing for a version of supersubstantivalism I call compresence supersubstantivalism. (shrink)

All physical theories, from classical Newtonian mechanics to relativistic quantum field theory, entail propositions concerning the geometric structure of spacetime. To give an example, the general theory of relativity entails that spacetime is curved, smooth, and four-dimensional. In this dissertation, I take the structural commitments of our theories seriously and ask: how is such structure instantiated in the physical world? Mathematically, a property like 'being curved' is perfectly well-defined insofar as we know what it means for a mathematical space to (...) be curved. But what could it mean to say that the physical world is curved? Call this the problem of physical geometry. The problem of physical geometry is a plea for foundations--a request for fundamental truth conditions for physical-geometric propositions. My chief claim is that only a substantival theory of spacetime--a theory according to which spacetime is an entity in its own right, existing over and above the material content of the world--can supply the necessary truth conditions. (shrink)

Is the world internally connected by a web of necessary connections or is everything loose and independent? Followers of David Hume accept the latter by upholding Hume’s Dictum, according to which there are no necessary connections between distinct existences. Roughly put, anything can coexist with anything else, and anything can fail to coexist with anything else. Hume put it like this: “There is no object which implies the existence of any other if we consider these objects in themselves.” Since Hume’s (...) day, Hume’s Dictum has played a major role in philosophy, especially in contemporary metaphysics. In ruling out necessary connections, Hume’s Dictum implies that causal relations and the laws of nature are contingent. It makes other demands on our metaphysics of science as well; for example, it places restrictions on our metaphysics of counterfactuals, dispositions, and explanation. The principle has applications in other areas too. Hume’s Dictum places constraints on our theories of abstract objects and moral properties. For example, Hume’s Dictum rules out the view that moral properties are distinct from, but necessarily connected to, non-moral properties. While Hume’s Dictum is a prominent principle in metaphysics, few Humeans have defended the principle at length. It is assumed more often than it is argued for. As a result, Hume’s Dictum no longer enjoys the reputation it once did. It’s common to hear complaints about the lack of arguments in support of Hume’s Dictum. Moreover, philosophers are increasingly willing to defend views that are at odds with Hume’s Dictum. A striking example of this is the recent explosion of interest in views that take causal relations and the laws of nature to be necessary. Humeans can no longer afford to be complacent. An extended defense of Hume’s Dictum is called for, and that’s what this dissertation aims to offer. This dissertation has three parts. In the first part, I lay out some preliminaries and offer a precise formulation of Hume’s Dictum. In the second part, I develop three arguments in favor of Hume’s Dictum. In the final part, I defend Hume’s Dictum against objections. (shrink)

Hilary Putnam once suggested that “the actual existence of sets as ‘intangible objects’ suffers… from a generalization of a problem first pointed out by Paul Benacerraf… are sets a kind of function or are functions a sort of set?” Sadly, he did not elaborate; my aim, here, is to do so on his behalf. There are well-known methods for treating sets as functions and functions as sets. But these do not raise any obvious philosophical or foundational puzzles. For that, we (...) first need to provide a full-fledged function theory. I supply such a theory: it axiomatizes the iterative notion of function in exactly the same sense that ZF axiomatizes the iterative notion of set. Indeed, this function theory is synonymous with ZF. It might seem that set theory and function theory present us with rival foundations for mathematics, since they postulate different ontologies. But appearances are deceptive. Set theory and function theory provide the very same judicial foundation for mathematics. They do not supply rival metaphysical foundations; indeed, if they supply metaphysical foundations at all, then they supply the very same metaphysical foundations. (shrink)

John MacFarlane explores how we might make sense of the idea that truth is relative. He provides new, satisfying accounts of parts of our thought and talk that have resisted traditional methods of analysis, including what we mean when we talk about what is tasty, what we know, what will happen, what might be the case, and what we ought to do.

This book is about the idea that some true statements would have been true no matter how the world had turned out, while others could have been false. It develops and defends a version of the idea that we tell the difference between these two types of truths in part by reflecting on the meanings of words. It has often been thought that modal issues—issues about possibility and necessity—are related to issues about meaning. In this book, the author defends the (...) view that the analysis of meaning is not just a preliminary to answering modal questions in philosophy; it is not merely that before we can find out whether something is possible, we need to get clear on what we are talking about. Rather, clarity about meaning often brings with it answers to modal questions. In service of this view, the author analyzes the notion of necessity and develops ideas about linguistic meaning, applying them to several puzzles and problems in philosophy of language. Meaning and Metaphysical Necessity will be of interest to scholars and advanced students working in metaphysics, philosophy of language, and philosophical logic. [See my homepage for a sample chapter.]. (shrink)

The philosophy of necessity and possibility has flourished in the last half-century, but much less attention has been paid to the question of how we know what can be the case and what must be the case. Many friends of modal metaphysics and many enemies of modal metaphysics have agreed that while empirical discoveries can tell us what is the case, they cannot shed much light on what must be the case or on what non-actual possibilities there are. In this (...) paper, in contrast, I discuss and defend naturalistic approaches to discovering the facts about necessity and possibility. After some remarks about what methodological naturalism in philosophy might amount to, I argue that naturalistic method in modal investigations may not need to be particularly revisionary of much of what is currently being done in modal investigation. I then discuss a number of respects in which a naturalistic orientation in modal investigation may improve on our current epistemic situation. (shrink)

The goal of this essay is twofold. First, it provides a quick look at the foundations of modern relational mechanics by tracing its development from Julian Barbour and Bruno Bertotti's original ideas until present-day's pure shape dynamics. Secondly, it discusses the most appropriate metaphysics for pure shape dynamics, showing that relationalism is more of a nuanced thesis rather than an elusive one. The chapter ends with a brief assessment of the prospects of pure shape dynamics in light of quantum physics.

Singularities in general relativity and quantum field theory are often taken not only to motivate the search for a more-fundamental theory (quantum gravity, QG), but also to characterise this new theory and shape expectations of what it is to achieve. Here, we first evaluate how particular types of singularities may suggest an incompleteness of current theories. We then classify four different 'attitudes' towards singularities in the search for QG, and show, through examples in the physics literature, that these lead to (...) different scenarios for the new theory. Two of the attitudes prompt singularity resolution, but only one suggests the need for a theory of QG. Rather than evaluate the different attitudes, we close with some suggestions of factors that influence the choice between them. (shrink)

In On the Plurality of Worlds (Lewis 1986), David Lewis imposes a condition on realist theories of modality which he calls ‘plenitude’. Lewis apparently assigns this condition considerable importance, and uses it to motivate his Humean principle of recombination, but he never says exactly what plenitude amounts to. This chapter first sets aside some obvious ways of reconstructing the plenitude criterion which do not fit with the textual evidence. An objection to modal realism due to John Divers and Joseph Melia (...) (Divers and Melia 2002) is diagnosed as equivocating between an overly-demanding plenitude constraint and a weaker constraint which fails to establish their conclusion. An alternative deflationary interpretation of the plenitude condition has it following from an application of standard theoretical virtues to a modal realist’s total theory; Lewis’ correspondence provides new evidence in support of this interpretation. The deflationary plenitude criterion also has broader application, beyond Lewisian modal realism. (shrink)

Lynne Baker’s case for the incompatibility of naturalism with the first-person perspective raises a range of questions about the relationship between naturalism and the various properties involved in first-person perspectives. After arguing that non-qualitative properties—most notably, haecceities like being Lynne Baker—are ineliminably tied to first-person perspectives, this paper considers whether naturalism and non-qualitative properties are, in fact, compatible. In doing so, the discussion focus on Shamik Dasupgta’s argument against individuals and, in turn, non-qualitative properties. Several strategies for undermining Dasgupta's argument (...) are considered, drawing on de re laws and haecceitistic possibilities. Finally, an analogy is drawn between naturalism and platonism regarding mathematical entities and naturalism's parallel commitment to individuals. I conclude that naturalists are obliged to posit non-qualitative properties. (shrink)

We care not only about what experiences we have, but when we have them too. However, on the B-theory of time, something’s timing isn’t an intrinsic way for that thing to be or become. Given B-theory, should we be rationally indifferent about the timing per se of an experience? In this paper, I argue that B-theorists can justify time-biased preferences for pains to be past rather than present and for pleasures to be present rather than past. In support of this (...) argument, I appeal to the doctrine of temporal parts or “four-dimensionalism” for short. When held in conjunction with a certain evaluative principle about whose experiences matter, four-dimensionalism reconciles B-theory with some time-biased preferences. (shrink)

This chapter analyzes several key themes in Kant’s views about modality. We begin with the pre-critical Only Possible Argument in Support of a Demonstration of the Existence of God, in which Kant distinguishes between formal and material elements of possibility, claims that all possibility requires an actual ground, and argues for the existence of a single necessary being. We then briefly consider how Kant’s views change in his mature period, especially concerning the role of form and thought in defining modality. (...) Kant’s mature views, however, present two difficult interpretive puzzles. The first puzzle concerns whether Kant has a generally reductive view of modality. While Kant’s views on logical modality, the role of actuality in grounding possibility, and the relation of modality to cognition all suggest reduction, we argue that the categorial status of modal concepts and the difficulty in even identifying amodal grounds for modal facts all suggest a non-reductive view. The second puzzle concerns whether Kant accepts modal facts or properties at the noumenal level. While Kant’s appeal to noumenal necessary connections, the contingency of noumenal willing, and the idea of a necessary noumenal being suggest that he endorses noumenal modality, his claims that modal concepts express only relations to the faculty of cognition and his claim that modal concepts arise from our distinctive psychological structures, we argue, suggest that he rejects noumenal modality. We conclude by considering potential solutions to these puzzles. (shrink)

It seems natural to ask why the universe exists at all. Modern physics suggests that the universe can exist all by itself as a self-contained system, without anything external to create or sustain it. But there might not be an absolute answer to why it exists. I argue that any attempt to account for the existence of something rather than nothing must ultimately bottom out in a set of brute facts; the universe simply is, without ultimate cause or explanation.

In this paper I explore irrealist alternatives to orthodox realism about grounding, and claim that at least some of these alternatives represent fertile areas for future discussion.

Could I have been someone other than who I am? Philosophers from Williams to Nagel to Lewis have been tempted to answer 'yes', but how can we make sense of such a view? I argue that to say that it is contingent who I am is to say that it is contingent what perspective I have, in a distinctively metaphysical sense of perspective.

First-order normative theories concerning what’s right and wrong, good and bad, etc. and metanormative theories concerning the nature of first-order normative thought and talk are widely regarded as independent theoretical enterprises. This paper argues that several debates in metanormative theory involve views that have first-order normative implications, even as the implications in question may not be immediately recognizable as normative. I first make my claim more precise by outlining a general recipe for generating this result. I then apply this recipe (...) to three debates in metaethics: the modal status of basic normative principles, normative vagueness and indeterminacy, and the determination of reference for normative predicates. In each case I argue that certain views on each issue carry first-order normative commitments, in accordance with my recipe. (shrink)

In this paper, I present a categorial theory of meaning which asserts that the meaning of a sentence is the function from the actualization of some potentiality or the potentiality of some actuality to the truth of the sentence. I argue that it builds on the virtues of David Lewis’s Possible World Semantics but advances beyond problems that Lewis’s theory faces with its distinctly Aristotelian turn toward actuality and potentiality.

This is a slightly opinionated review of three main factions in metaontology: Quineans, Carnapians, and Meinongians. Emphasis is given to the last camp, as the metaontological aspect of Meinongianism has been underappreciated. The final section then offers some general remarks about the legitimacy of ontology, touching on ideas I have developed in other publications.

A primer on the philosophical issues relating to phenomenal consciousness, part of a collection of new papers by scientists and philosophers on the constitution of consciousness.

It’s a platitude that a picture is realistic to the degree to which it resembles what it represents (in relevant respects). But if properties are abundant and degrees of resemblance are proportions of properties in common, then the degree of resemblance between different particulars is constant (or undefined), which is inconsonant with the platitude. This paper argues this problem should be resolved by revising the analysis of degrees of resemblance in terms of proportion of properties in common, and not by (...) accepting a sparse theory of properties or by denying that degree of realism is degree of resemblance (in relevant respects). (shrink)

Existence as reflected in natural language is not a univocal notion, but divides into different modes of being, such as existence (as, roughly, endurance) and occurrence. One aim of the paper is to distinguish sharply between abstract artifacts and non-existent objects (e.g., plans vs. planned events that fail to occur); another is to argue for validity as a mode of being distinct from existence, as well as for corresponding distinctions among non-being.

I explore a challenge that idealisations pose to scientific realism and argue that the realist can best accommodate idealisations by capitalising on certain modal features of idealised models that are underwritten by laws of nature.

In the Phaedrus, Socreates sympathetically describes the ability “to cut up each kind according to its species along its natural joints, and to try not to splinter any part, as a bad butcher might do.” (265e) In contemporary philosophy, Ted Sider (2009, 2011) defends the same idea. As I shall put it, Plato and Sider’s idea is that limning structure is an epistemic goal. My aim in this paper is to articulate and defend this idea. First, I’ll articulate the notion (...) of a structural proposition (§1), and the notion of an epistemic goal (§2), where I’ll assume that epistemic goals are species of accuracy. Then (§3), I’ll argue against some proposals for understanding the idea that limning structure is an epistemic goal: limning structure is neither an aim of belief (§3.1), nor of inquiry (§3.2), nor of concept possession (§3.3). Importantly, non-structural belief is not thereby inaccurate; belief does not “aim” at being structural. Next (§4), I’ll propose a framework for understanding the idea that limning structure is an epistemic goal, and defend that idea. What is required, to defend the view that limning structure is an epistemic goal, is the notion of (what I call) theorizing – a propositional attitude that, unlike belief, does “aim” at being structural (§4.1). I’ll argue that structural truths constitute a species of “important” truths (§4.2), and that apt theorizing is a species of understanding (§4.3). Finally (§5), I’ll discuss the possibility that there is no structure. (shrink)

Many people think that truth somehow depends upon the way things are. Yet, it has proven difficult to precisely explain the nature of this dependence. The most common view is that truth depends upon the way things are by corresponding to things. But this account relocates the difficulty: one now wonders what correspondence is. It is worth emphasizing that the question of how truth relates to reality is not only a question for correspondence theorists; theorists of all stripes may wonder (...) how truth and reality connect. There are many reasons one might care to have an analysis of how truth relates to reality. Here are two. First, an analysis would help philosophers better understand how truth could depend upon the way things are. Why is it that when Joe shoves his cat off his pillow, the proposition that Joe's cat is on his pillow switches from true to false? It may seem puzzling that an abstract thing, such as a proposition, should be affected by physical changes to concrete particulars. How does that happen? The difficulty of seeing just how true propositions are able to systematically relate to reality will be called "the Problem of Matching." A thorough analysis of the relationship between truth and reality would effectively solve the Problem of Matching. (shrink)

There are writers in both metaphysics and algorithmic information theory (AIT) who seem to think that the latter could provide a formal theory of the former. This paper is intended as a step in that direction. It demonstrates how AIT might be used to define basic metaphysical notions such as *object* and *property* for a simple, idealized world. The extent to which these definitions capture intuitions about the metaphysics of the simple world, times the extent to which we think the (...) simple world is analogous to our own, will determine a lower bound for basing a metaphysics for *our* world on AIT. (shrink)

This chapter examines the status of inference to the best explanation in naturalistic metaphysics. The methodology of inference to the best explanation in metaphysics is studied from the perspective of contemporary views on scientific explanation and explanatory inferences in the history and philosophy of science. This reveals serious shortcomings in prevalent attempts to vindicate metaphysical "explanationism" by reference to similarities between science and naturalistic metaphysics. This critique is brought out by considering a common gambit of methodological unity: (1) Both metaphysics (...) and science employ inference to the best explanation. (2) One has no reason to think that if explanationism is truth-conducive in science, it is not so in metaphysics. (3) One has a positive reason to think that if explanationism is truth-conducive in science, it is also so in metaphysics. (shrink)

Relativized Metaphysical Modality (RMM: Murray and Wilson, 'Relativized metaphysical modality', Oxford Studies in Metaphysics, 2012; Murray, Perspectives on Modal Metaphysics, 2017) exploits 'two-dimensionalist' resources to metaphysical, rather than epistemological, ends: the second dimension offers perspective-dependence without contingency, diverting attacks on 'Classical' analyses of modals (in effect, analyses validating S5 and the Barcan Formulae). Here, we extend the RMM program in two directions. First, we harvest resources for RMM from Lewis's 1980 'Context--Index' (CI) framework: (a) the ban in CI on binding (...) into context-arguments (akin to Kaplan's 'monstrosity' ban) projects a bright line between perspective-dependence and contingency; and (b) CI-postulated connections among meaning, content, truth, argument-structure, context, and modality collectively generate a 'Generalized Humphrey Problem' for any non-Classical analysis (examples covered include appeals to accessibility, contingent domains, and counterpart relations). Second, we sharpen the tools of RMM-based metaphysical analysis, and extend their domain of coverage across familiar anomalies for Classical modals: we revisit earlier RMM-based bulwarks for S5 (against 'Chisholm's Paradox' for moderate flexibility of essence, and nomological necessitarianism); and we now similarly shore up the Barcan Formulae (against the apparent contingency of existence and nonexistence). (shrink)

Possible worlds have found many applications in contemporary philosophy: from theories of possibility and necessity, to accounts of conditionals, to theories of mental and linguistic content, to understanding supervenience relationships, to theories of properties and propositions, among many other applications. Almost as soon as possible worlds started to be used in formal theories in logic, philosophy of language, philosophy of mind, metaphysics, and elsewhere, theorists started to wonder whether impossible worlds should be postulated as well. In many applications, possible worlds (...) face limitations that can be dealt with through postulating impossible worlds as well. This chapter examines some of the uses of impossible worlds, and philosophical challenges theories of impossible worlds face. (shrink)

Can identity itself be vague? Can there be vague objects? Does a positive answer to either question entail a positive answer to the other? In this paper we answer these questions as follows: No, No, and Yes. First, we discuss Evans’s famous 1978 argument and argue that the main lesson that it imparts is that identity itself cannot be vague. We defend the argument from objections and endorse this conclusion. We acknowledge, however, that the argument does not by itself establish (...) either that there cannot be vague objects or that there cannot be identity statements that are indeterminate for ontic reasons. And we further acknowledge that it does not by itself establish that there cannot be identity statements that are indeterminate in virtue of the existence of vague objects. We then go on to argue that, despite this, one who believes in vague objects cannot endorse Evans’s argument. To establish this we offer supplementary arguments that show that if vague objects exist then identity is vague, and that if identity is vague then vague objects exist. Finally we draw attention to an argument parallel to that of Evans’s, but safer, which can be employed against the putative ontic indeterminacy in identity of vague objects which can be differentiated by identity-free properties. (shrink)

A naïve perspective on the world suggests that the world we live in is full of vague objects. In this chapter, a version of the supervaluationist framework will be proposed to provide a systematic conception of such a naïve perspective. Precisifications of a vague object will be characterized as objects that, were they actual objects, every determinate truth about the vague object would be true about them. It will be argued that this view is more effective than other versions of (...) supervaluationism at accommodating commonsensical and metaphysical considerations. The view leaves room for vague identity as a kind of “no fact of the matter.” Thus, Evans’ argument against ontic vagueness fails in a natural way. (shrink)

Formal ontology as a main branch of metaphysics investigates categories of being. In the formal ontological approach to metaphysics, these ontological categories are analysed by ontological forms. This analysis, which we illustrate by some category systems, provides a tool to assess the clarity, exactness and intelligibility of different category systems or formal ontologies. We discuss critically different accounts of ontological form in the literature. Of ontological form, we propose a character- neutral relational account. In this metatheory, ontological forms of entities (...) are their standings in internal relations whose holding is neutral on the character of their relata. These relations are “formal ontological relations”. Entities belong to ontological categories because they stand in the same formal ontological relations. We hold a nominalist relationalism about ontological categories and forms. We conclude by showing that our metatheory is useful for understanding categorial fundamentality/non- fundamentality, different formal ontologies, and for unifying metaphysical questions. (shrink)

This is a prepublication version of my book Objects and Attitudes. The book develops a novel semantics of attitude reports, modal sentences, and quotation based on the view that sentences semantically act as predicates of various attitudinal and modal objects, entities like claims, requests, promises, obligations, and permissions, rather than standing for abstract propositions playing the role of objects. The approach develops truthmaker semantics for attitudinal and modal objects and has a wide range of applications to issues in philosophy of (...) language, semantics, and philosophy of mind. (shrink)

In light of the problem of logical omniscience, some scholars have argued that belief is question-sensitive: agents don't simply believe propositions but rather believe answers to questions. Hoek (2022) has recently developed a version of this approach on which a belief state is a "web" of questions and answers. Here, we present several challenges to Hoek's question-sensitive account of belief. First, Hoek's account is prone to very similar logical omniscience problems as those he claims to address. Second, the link between (...) belief and action he proposes is too rigid. We close by sketching a generalization of the account that can meet these challenges. (shrink)

One motivation for preferring the many worlds interpretation of quantum mechanics over realist rivals, such as collapse and hidden variables theories, is that the interpretation is able to preserve locality (in the sense of no action at a distance) in a way these other theories cannot. The primary goal of this paper is to make this argument for the many worlds interpretation precise, in a way that does not rely on controversial assumptions about the metaphysics of many worlds.

Time and modality show remarkable similarities. Each of the most discussed theories in philosophy of time finds an analogous counterpart in modal metaphysics, suggesting that the parallel between the two notions is metaphysically deep. This chapter offers a brief overview of their analogies. Section 1 addresses the analogy between presentism and actualism. Section 2 explores the analogy between non-presentist theories and possibilism. Section 3 discusses the analogy between temporal and modal persistence.