This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

How do we explain the truth of true propositions? Truthmaker theory is the branch of metaphysics that explores the relationships between what is true and what exists. It plays an important role in contemporary debates about the nature of metaphysics and metaphysical enquiry. -/- In this book Jonathan Tallant argues, controversially, that we should reject truthmaker theory. In its place he argues for an 'explanationist' approach. Drawing on a deflationary theory of truth he shows that it allows us to explain (...) the truth of true propositions and respond to recent arguments that purport to show otherwise. He augments this with a distinction between internally and externally quantified claims: externally quantified claims are claims that quantify over elements of our ontology that play an indispensable explanatory role; internally quantified claims do not. He deploys this union of deflationism and a distinction between kinds of quantification to pursue metaphysical inquiry, sketching the implications for a number of first-order debates, including those in the philosophy of time, modality and mathematics, and also shows how this explanationist model can be used to solve the key problems that afflicted truthmaker theory. -/- Truth and the World is an important contribution to debates about truth and truthmaker theory as well as metametaphysics, the metaphysics of time and the metaphysics of mathematics, and is essential reading for students and scholars engaged in the study of these topics. (shrink)

Here, I defend the view that there is no sensible way to pin a truth-maker objection on presentism. First, I suggest that if we adopt truth-maker maximalism then the presentist can requisition appropriate ontological resources with impunity. Second, if we deny maximalism, then the presentist can sensibly restrict the truth-maker principle in order to avoid the demand for truth-makers for talk about the non-present.

1. IntroductionA popular view in metaphysics is that which propositions are true depends upon how the world is . In more evocative language, truth requires ground. This thought then gets used to do some serious work. As Sider has it, ‘[t]he point of … the principle that truth supervenes on being is to rule out dubious ontologies’. Here, I argue that ‘dubious’ ontologies are theoretically virtuous.

I thank my commentators for their kind words, and for their close reading and challenging criticisms of my book. I have chosen selective and substantive replies. Those criticisms I ignore, I ignore because I have little more to say, not because they are unworthy of discussion.

Persistence through time is like extension through space. A road has spatial parts in the subregions of the region of space it occupies; likewise, an object that exists in time has temporal parts in the various subregions of the total region of time it occupies. This view — known variously as four dimensionalism, the doctrine of temporal parts, and the theory that objects “perdure” — is opposed to “three dimensionalism”, the doctrine that things “endure”, or are “wholly present”.1 I will (...) attempt to resolve this dispute in favor of four dimensionalism by means of a novel argument based on considerations of vagueness. But before argument in this area can be productive, I believe we must become much clearer than is customary about exactly what the dispute is, for the usual ways of formulating the dispute are flawed, especially where three dimensionalism is concerned. (shrink)

Truth and Ontology is a lively book, brimming with arguments, and drawing the reader towards the radical conclusion that what is true does not depend on what there is. If there is a central line of argument, it is that the best account of truthmaking requires truths to be about their truthmakers, but negative existentials, modals, and claims about the past and future are not about what is, but rather about what is not, what might be, and what was and (...) will be. (shrink)

Peter Milne has tried to refure Truthmaker Maximalism. the thesis that every truth has a truthmaker, by producing a simple and direct counterexample to it, the sentence M: This sentence has no truthmaker. I argue that, contrary to what Milne argues, on Truthmaker Maximalism M is equivalent to the Liar, which gives the truthmaker maximalist a way to defend his position from Milne's counterexample: to argue that M expresses no proposition.

In this book Terence Parsons revives the older tradition of taking such objects at face value. Using various modern techniques from logic and the philosophy of language, he formulates a metaphysical theory of nonexistent objects. The theory is given a formalization in symbolism rich enough to contain definite descriptions, modal operators, and epistemic contexts, and the book includes a discussion which relates the formalized theory explicitly to English.

First paragraph: Truthmaker theory maintains that for every truth there is something, some thing, some entity, that makes it true. Balking at the prospect that logical truths are made true by any particular thing, a consequence that may in fact be hard to avoid (see Restall 1996, Read 2000), this principle of truthmaking is sometimes restricted to (logically) contingent truths. I aim to show that even in its restricted form, the principle is provably false.

This is my contribution to an author-meets-critics session on Truth and Ontology.

Jonathan Westphal's recent paper attempts to reconcile the view that propositions about the future can be true or false now with the idea that the future cannot now be real. I attempt to show that Westphal's proposal is either unoriginal or unsatisfying. It is unoriginal if it is just the well-known eternalist solution. It is unsatisfying if it is instead making use of a peculiar, tensed truthmaking principle.

In this paper, I formulate, elucidate, and defend a version of modal realism with overlap, the view that objects are literally present at more than one possible world. The version that I defend has several interesting features: (i) it is committed to an ontological distinction between regions of spacetime and material objects; (ii) it is committed to compositional pluralism, which is the doctrine that there is more than one fundamental part-whole relation; and (iii) it is the modal analogue of endurantism, (...) which is the doctrine that objects persist through time by being wholly present at each moment they are located. (shrink)

When there is truth, there must be some thing (or things) to account for that truth: some thing(s) that couldn’t exist and the true proposition fail to be true. That is the truthmaker principle. True propositions are made true by entities in the mind-independently existing external world. The truthmaker principle seems attractive to many metaphysicians, but many have wanted to weaken it and accept not that every true proposition has a truthmaker but only that some important class of propositions require (...) truthmakers.1 Let us, following Armstrong, call the claim that all true propositions, without exception, have a truthmaker, Truthmaker Maximalism. Why might one be tempted to the spirit of truthmaker theory but reject Truthmaker Maximalism? Well, you might deny that necessary truths need truthmakers, for one, and insist that only contingent truths have truthmakers. But I think it’s fair to say that the most common motivation for rejecting maximalism concerns negative truths. The thought that negative truths are exempt from the demand for truthmakers could be justified in one of two ways: there is the claim that we don’t need truthmakers for negative truths, and there is the claim that we can’t have.. (shrink)

Fictionalism about fictional characters is a view according to which all claims ostensibly about fictional characters are in fact claims about the content of a story. Claims that appear to refer to or quantify over fictional objects contain an implicit prefix of the form “according to such-and-such story. In.

Challenging the myth that mathematical objects can be defined into existence, Bigelow here employs Armstrong's metaphysical materialism to cast new light on mathematics. He identifies natural, real, and imaginary numbers and sets with specified physical properties and relations and, by so doing, draws mathematics back from its sterile, abstract exile into the midst of the physical world.

In this paper I consider the aboutness objection against standard truth-preserving presentism (STP). According to STP: (1) past-directed propositions (propositions that seem to be about the past) like , are sometimes true (2) truth supervenes on being and (3) the truth of past-directed propositions does not supervene on how things were, in the past. According to the aboutness objection (3) is implausible, given (1) and (2): for any proposition, P, P ought to be true in virtue of what P is (...) about, and so it is upon the past that the truth of past-directed propositions ought to supervene. Although an objection along these lines has been offered previously, I press the objection in two ways. First, by providing needed support for the view that propositions ought to be true in virtue of what they are about and, second, by arguing that the two responses available to the proponent of STP fail to be compelling. (shrink)

Recently, nominalists have made a case against the Quine–Putnam indispensability argument for mathematical Platonism by taking issue with Quine’s criterion of ontological commitment. In this paper I propose and defend an indispensability argument founded on an alternative criterion of ontological commitment: that advocated by David Armstrong. By defending such an argument I place the burden back onto the nominalist to defend her favourite criterion of ontological commitment and, furthermore, show that criterion cannot be used to formulate a plausible form of (...) the indispensability argument. (shrink)

Explanation has played myriad roles in truthmaker theory. The notion of explanation is sometimes thought to give content to the very idea of truthmaking, and is sometimes used as a weapon to undermine the entire point of truthmaker theory. I argue that the notion of explanation is dialectically useless in truthmaker theory: while it’s true that truthmaking offers a form of explanation, this claim is theoretically unilluminating, and leaves truthmaker theorists vulnerable to various kinds of attack. I advocate an alternative (...) approach to truthmaker theory that downplays the role of explanation, and show how it releases the enterprise from a variety of problematic commitments that have troubled truthmaker theorists. The “ontology-first” approach to truthmaking that I advocate not only restores the initial impulse behind truthmaking, but also has a number of theoretical advantages. Most prominently, it dodges the infamous problem of negative existentials, and lessens truthmaker theory’s dependence on contentious intuitive judgments about both explanation and truthmaking. (shrink)

Creeping minimalism threatens to cloud the distinction between realist and anti-realist metaethical views. When anti-realist views equip themselves with minimalist theories of truth and other semantic notions, they are able to take on more and more of the doctrines of realism (such as the existence of moral truths, facts, and beliefs). But then they start to look suspiciously like realist views. I suggest that creeping minimalism is a problem only if moral realism is understood primarily as a semantic doctrine. I (...) argue that moral realism is better understood instead as a metaphysical doctrine. As a result, we can usefully regiment the metaethical debate into one about moral truthmakers: in virtue of what are moral judgments true? I show how the notion of truthmaking has been simmering just below the surface of the metaethical debate, and how it reveals one metaethical view (quasi-realism) to be a stronger contender than the others. (shrink)

Kit Fine, the leading proponent of the metaphysical project of grounding theory, has offered a number of potentially devastating objections to truthmaker theory, the branch of metaphysics dedicated to exploring the ontological grounds for truths. In this paper I show what presuppositions about truthmaker theory Fine’s objections are based upon, and why they are false. I discuss four objections that Fine raises, and demonstrate how truthmaker theorists may respond to them. I then showcase the positive contribution that truthmaker theory can (...) make to metaphysics, including its ability to speak to a core metaphysical topic (the ontological grounds for truths) that Fine’s approach to grounding must ultimately remain silent on. I conclude by exploring what I take to be the best option when it comes to understanding how truthmaking and grounding fit together. (shrink)

Realism and anti-realism about a domain of thought are metaphysical theses that involve the natures of the truthmakers in that domain and the truthmaking relation that is operant in the domain. Truthmaker theory is not exclusive territory for realists: anti-realist views are also best understood in terms of how they understand truthmakers and truthmaking. In particular, I explore the possibility of projectivist truthmaking, and show how it makes sense of quasi-realism. In addition to critically examining some extant accounts of the (...) relationship between realism and truthmaking, I offer an account that best captures the nature of the various realism debates. (shrink)

In this important study D. M. Armstrong offers a comprehensive system of analytical metaphysics that synthesises but also develops his thinking over the last twenty years. Armstrong's analysis, which acknowledges the 'logical atomism' of Russell and Wittgenstein, makes facts the fundamental constituents of the world, examining properties, relations, numbers, classes, possibility and necessity, dispositions, causes and laws. All these, it is argued, find their place and can be understood inside a scheme of states of affairs. This is a comprehensive and (...) rigorously this-worldly account of the most general features of reality, argued from a distinctive philosophical perspective, and it will appeal to a wide readership in analytical philosophy. (shrink)

Tim Crane addresses the ancient question of how it is possible to think about what does not exist. He argues that the representation of the non-existent is a pervasive feature of our thought about the world, and that to understand thought's representational power ('intentionality') we need to understand the representation of the non-existent.

Modal realism -- Time, space, world -- Existence -- Actuality -- Modal realism and modal tense -- Transworld individuals and their identity -- Existensionalism -- Impossibility -- Proposition and relief -- Fictional worlds -- Epistemology.

Truth and Ontology concludes that some truths do not depend on being in any substantive way at all.

Truths are determined not by what we believe, but by the way the world is. Or so realists about truth believe. Philosophers call such theories correspondence theories of truth. Truthmaking theory, which now has many adherents among contemporary philosophers, is the most recent development of a realist theory of truth, and in this book D. M. Armstrong offers the first full-length study of this theory. He examines its applications to different sorts of truth, including contingent truths, modal truths, truths about (...) the past and the future, and mathematical truths. In a clear, even-handed and non-technical discussion he makes a compelling case for truthmaking and its importance in philosophy. His book marks a significant contribution to the debate and will be of interest to a wide range of readers working in analytical philosophy. (shrink)

A number of philosophers have recently become receptive to the idea that, in addition to scientific or causal explanation, there may be a distinctive kind of metaphysical explanation, in which explanans and explanandum are connected, not through some sort of causal mechanism, but through some constitutive form of determination. I myself have long been sympathetic to this idea of constitutive determination or ‘ontological ground’; and it is the aim of the present paper to help put the idea on a firmer (...) footing - to explain how it is to be understood, how it relates to other ideas, and how it might be of use in philosophy. (shrink)

When I profess realism about possible worlds, I mean to be taken literally. Possible worlds are what they are, and not some other thing. If asked what sort of thing they are, I cannot give the kind of reply my questioner probably expects: that is, a proposal to reduce possible worlds to something else. I can only ask him to admit that he knows what sort of thing our actual world is, and then explain that possible worlds are more things (...) of that sort, differing not in kind but only in what goes on at them. (shrink)