According to actualism, modal reality is constructed out of valuations (combinations of truth values for all propositions). According to possibilism, modal reality consists in a set of possible worlds, conceived as independent objects that assign truth values to propositions. According to possibilism, accounts of modal reality can intelligibly disagree with each other even if they agree on which valuations are contained in modal reality. According to actualism, these disagreements (possibilist disagreements) are completely unintelligible. An essentially actualist semantics for modal propositional (...) logic specifies which sets of valuations are compatible with the meanings of the truth-functional connectives and modal operators without drawing on formal resources that would enable us to represent possibilist disagreements. The paper discusses the availability of an essentially actualist semantics for modal propositional logic. I argue that the standard Kripkean semantics is not essentially actualist and that other extant approaches also fail to provide a satisfactory essentially actualist semantics. I end by describing an essentialist actualist semantics for modal propositional logic. (shrink)

The standard Kripkean semantic theories for quantified modal logic allow the individuals that exist at other worlds to vary from those that exist at the actual world. This causes a problem for those who deny the existence of non-actual individuals. I focus on two prominent strategies for solving this problem, due respectively to Bernard Linsky and Edward Zalta (who identify the possible individuals with the actual individuals) and Alvin Plantinga (who identifies the possible individuals with the individual essences). I argue, (...) contra various commentators, that both of these solutions are acceptable by the lights of those who deny the existence of mere possibilia. (shrink)

The common assumption in the debate between the A- and B-theories is that there is a difference between A- and B-time. A-time has been said to be characterized by a flow, whereas B-time has been said not to consist of a flow. This way of construing the debate, however, is mistaken. Both A- and B-time possess "flow" or transition. But if this is so, we need to ask how B-time flow differs from A-time flow. I argue that none of the (...) ways in which the difference has been characterized is satisfactory. My conclusion is that the debate between A- and B-time either needs to be recast or given up. (shrink)

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)

Abstract:In this paper I will first contend that semantically based arguments in favour of or against problematic entities—like those provided, respectively, in a realist Meinongian and in an antirealist Russellian camp—are ultimately inconclusive. Indeed, only genuinely ontological arguments, specifically addressed to prove (or to reject) the existence of entities of a definite kind, suit the purpose. Thus, I will sketch an argument intended to show that there really are entities of an apparently specific kind, i.e. intentionalia, broadly conceived as things (...) that may actually exist as well as actually not exist. Finally, I will try to explain why that argument proves the existence of only some sorts of intentionalia, by showing how this is related to the fact that, as some have correctly maintained, intentionalia have no intrinsic nature. (shrink)

The best arguments for possible worlds as states of affairs furnish us with equally good arguments for impossible worlds of the same sort. I argue for a theory of impossible worlds on which the impossible worlds correspond to maximal inconsistent classes of propositions. Three objections are rejected. In the final part of the paper, I present a menu of impossible worlds and explore some of their interesting formal properties.

Philosophers often explain what could be the case in terms of what is, in fact, the case at one possible world or another. They may differ in what they take possible worlds to be or in their gloss of what is for something to be the case at a possible world. Still, they stand united by the threat of paradox. A family of paradoxes akin to the set-theoretic antinomies seem to allow one to derive a contradiction from apparently plausible principles. (...) Some of them concern the interaction between propositions and worlds, and they appear to afford the means to map classes of propositions into propositions – or, likewise, classes of worlds into worlds – in a one-to-one fashion that leads to contradiction. Yet another family of paradoxes threaten the view that whatever could exist does, in fact, exist, which is in line with modal realism, for example. This article aims to survey and identify the source of each family of paradoxes as well as to outline some responses to them. (shrink)

Bertrand Russell offered an influential paradox of propositions in Appendix B of The Principles of Mathematics, but there is little agreement as to what to conclude from it. We suggest that Russell's paradox is best regarded as a limitative result on propositional granularity. Some propositions are, on pain of contradiction, unable to discriminate between classes with different members: whatever they predicate of one, they predicate of the other. When accepted, this remarkable fact should cast some doubt upon some of the (...) uses to which modern descendente of Russell's paradox of propositions have been put in recent literature. (shrink)

A‐theorists of time postulate a deep distinction between the present, past and future. Settling on an appropriate logic for such a view is no easy matter. This Philosophy Compass article describes one of the most vexing formal problems facing A‐theorists. It is commonly thought that A‐theories can only be formally expressed in a tense logic: a logic with operators like P and F . And it seems natural to think that we live in a world where objects come to exist (...) and cease to exist as time passes. Indeed, this is typically a key component of the most prominent kind of A‐theory, presentism. But the temporary existence assumption cannot be upheld in any tense logic with a standard quantification theory. I will explain the problem and outline the philosophical and logical considerations that generate it. I will then consider two possible solutions to the problem – one that targets our logic of quantification and one that targets our assumptions about change. I survey the costs of each solution. (shrink)

Pantheism claims: (1) there exists an all-inclusive unity; and (2) that unity is divine. I review three current and scientifically viable ontologies to see how pantheism can be developed in each. They are: (1) materialism; (2) Platonism; and (3) class-theoretic Pythagoreanism. I show how each ontology has an all-inclusive unity. I check the degree to which that unity is: eternal, infinite, complex, necessary, plentiful, self-representative, holy. I show how each ontology solves the problem of evil (its theodicy) and provides for (...) salvation (its soteriology). I conclude that Platonism and Pythagoreanism have the most divine all-inclusive unities. They support sophisticated contemporary pantheisms. (Published Online February 17 2004). (shrink)

Christian Platonism and Divine Simplicity remain the most commonly discussed views with respect to the way in which Christians ought to conceive of God’s nature and properties. In this essay, I suggest that we ought to consider seriously two versions of a quite different view, namely, what I call “the Nominalized Composite God View.” Both versions of the Nominalized Composite God View share two features: (1) they treat God as metaphysically composite, in opposition to Divine Simplicity, and (2) they deny (...) that God has God’s properties in virtue of instantiating abstractly existing universals, in opposition to Christian Platonism. (shrink)

I discuss Stalnaker’s views on modality. In particular, his views on actualism, anti-essentialism, counterpart theory, and the Barcan formulas.

There is a salient contrast in how theoretical representations are regarded. Some are regarded as revealing the nature of what they represent, as in familiar cases of theoretical identification in physical chemistry where water is represented as hydrogen hydroxide and gold is represented as the element with atomic number 79. Other theoretical representations are regarded as serving other explanatory aims without being taken individually to reveal the nature of what they represent, as in the representation of gold as a standard (...) for pre-20th century monetary systems in economics or the representation of the meaning of an English sentence as a function from possible worlds to truth values in truth-conditional semantics. Call the first attitude towards a theoretical representation *realist* and the second attitude *instrumentalist*. Philosophical explanation purports to reveal the nature of whatever falls within its purview, so it would appear that a realist attitude towards its representations is a natural default. I offer reasons for skepticism about such default realism that emerge from attending to several case studies of philosophical explanation and drawing a general metaphilosophical moral from the foregoing discussion. (shrink)

This is a symposium on my book, Writing the Book of the World, containing a precis from me, criticisms from Contessa, Merricks, and Schaffer, and replies by me.

According to Timothy Williamson, we should accept the simplest and most powerful second-order modal logic, and as a result accept an ontology of "bare possibilia". This general method for extracting ontology from logic is salutary, but its application in this case depends on a questionable assumption: that modality is a fundamental feature of the world.

Joseph LaPorte in an article on `Kind and Rigidity'(Philosophical Studies, Volume 97) resurrects an oldsolution to the problem of how to understand the rigidityof kind terms and other general terms. Despite LaPorte'sarguments to the contrary, his solution trivializes thenotion of rigidity when applied to general terms. Hisarguments do lead to an important insight however. Thenotions of rigidity and non-rigidity do not usefullyapply at all to kind or other general terms. Extendingthe notion of rigidity from singular terms such as propernames to (...) general terms such as natural kind terms is amistake. (shrink)

Is everything about reality either qualitative or somehow determined by the qualitative character of reality itself? Metaphysical anti-Haecceitism is often taken to be the claim that this is the case, and to entail that reality is fundamentally qualitative. In this paper, I (1) argue against the idea that metaphysical anti-Haecceitism should be characterized in such terms, and (2) defend a novel way to phrase such a view. This will be done by taking the main arguments for anti-Haecceitism as a guide (...) and by singling out the proper commitments of a view that satisfies thedesideratumset forth by such arguments. The phrasing I shall offer will help tell the issue of anti-Haecceitism apart from some concerns about fundamentality that, I will contend, are orthogonal to it—among them, the question whether there is fundamentality at all. (shrink)

Is everything about reality either qualitative or somehow determined by the qualitative character of reality itself? Metaphysical anti-Haecceitism is often taken to be the claim that this is the case, and to entail that reality is fundamentally qualitative. In this paper, I (1) argue against the idea that metaphysical anti-Haecceitism should be characterized in such terms, and (2) defend a novel way to phrase such a view. This will be done by taking the main arguments for anti-Haecceitism as a guide (...) and by singling out the proper commitments of a view that satisfies the desideratum set forth by such arguments. The phrasing I shall offer will help tell the issue of anti-Haecceitism apart from some concerns about fundamentality that, I will contend, are orthogonal to it—among them, the question whether there is fundamentality at all. (shrink)

This document collects natural derivation systems for logics described in Priest, An Introduction to Non-Classical Logic [4]. It provides an alternative or supplement to the semantic tableaux of his text. Except that some chapters are collapsed, there are sections for each chapter in Priest, with an additional, final section on quantified modal logic. In each case, (i) the language is briefly described and key semantic definitions stated, (ii) the derivation system is presented with a few examples given, and (iii) soundness (...) and completeness are proved. There should be enough detail to make the parts accessible to students would work through parallel sections of Priest. (shrink)

Some metaphysicians believe that metaphysical modality is explainable by the essences of objects. In §II, I spell out the definitional view of essence, and in §III, a working notion of metaphysical explanation. Then, in §IV, I consider and reject five natural ways to explain necessity by essence: in terms of the principle that essential properties can't change, in terms of the supposed obviousness of the necessity of essential truth, in terms of the logical necessity of definitions, in terms of Fine's (...) logic of essence, and in terms of the theory of real definitions. I will conclude that the present evidence favours rejecting the hypothesis that modality is explainable by essence. (shrink)

The question as to whether some objects are possible worlds that have an initial segment in common, i.e. so that their fusion is a temporal tree whose branches are possible worlds, arises both for those who hold that our universe has the structure of a temporal tree and for those who hold that what there is includes concrete universes of every possible variety. The notion of “possible world” employed in the question is seen to be the notion of an object (...) of a kind such that objects of that kind play a certain theoretical role. Lewis’s discussion of the question is thereby clarified but is nevertheless inadequate; his negative answer is correct but even from his combinatorialist viewpoint the rationale he provides for this answer is misguided. I explain why the combinatorialist advocate of concrete plenitude should hold that no object is a tree of possible worlds. Then I explain that for a different reason the nomic essentialist advocate of concrete plenitude should hold this much too. (shrink)

The paper proposes a simple method for constructing ontological theories—an ‘ontology generator’. It shows that such a generator manages to produce major existing ontological theories, e.g., Realism, Nominalism, Trope theory, Bundle theory, Perdurantism, Endurantism, Possibilism, Actualism and more. It thus turns out, surprisingly, that all these seemingly unrelated different ontological theories that were designed by thinkers hundreds of years apart, can all be generated using the same simple mechanism. Moreover, this same generator manages to produce entirely novel ontological theories, that (...) fare no worse than existing ones in meeting the same common metaphysical challenges. (shrink)

The nonexistence of fictional entities does not seem incompatible with their possible existence. The aim of this paper is to give an account of the intuitive truth of statements of possible existence involving fictional proper names in an actualist framework. After having clarified the opposition between a possibilist and an actualist approach of possible wolds, I distinguish fictional individuals from fictional characters and the fictional use of fictional proper names from their metafictional use. On that basis, statements of possible existence (...) involving fictional proper names literally say of fictional characters conceived as abstract objects that they might have been exemplified. (shrink)

The mere fact that ontological debates are possible requires us to address the question, what is it to claim that a certain entity or kind of entity exists—in other words, what do we do when we make an existence-claim? I develop and defend one candidate answer to this question, namely that to make an existence-claim with regard to Fs is to claim that we can refer to Fs. I show how this theory can fulfil the most important explanatory desiderata for (...) a theory of existence; I also defend it against the charges of illegitimate ‘semantic ascent’ and of making existence counterfactually dependent on human linguistic ability. (shrink)

This paper attacks the modal ontological argument, as advocated by Plantinga among others. Whereas other criticisms in the literature reject one of its premises, the present line is that the argument is invalid. This becomes apparent once we run the argument assuming fictionalism about possible worlds. Broadly speaking, the problem is that if one defines “x” as something that exists, it does not follow that there is anything satisfying the definition. Yet unlike non-modal ontological arguments, the modal argument commits this (...) “existential fallacy” not in relation to the definition of ‘God’. Rather, it occurs in relation to the modal facts quantified over within a Kripkean modal logic. In brief, we can describe the modal facts by whichever logic we prefer—yet it does not follow that there are genuine modal facts, as opposed to mere facts-according-to-the-fiction. A broader consequence of the discussion is that the existential fallacy is an issue for many projects in “armchair metaphysics.”. (shrink)

Externalism holds that the content of our utterances and thoughts are determined partly by the environment. Here, I offer an argument which suggests that externalism is incompatible with a natural view about ontological commitment--namely, the Quinean view that such commitments are fixed by the range of the variables in your theory. The idea in brief is that if Oscar mistakenly believes that water = XYZ, the externalist ontologically commits Oscar to two waterish kinds, whereas the Quinean commits him to one (...) such kind (albeit a metaphysically impossible kind). The penultimate section addresses a variety of objections to the argument. (shrink)

Our paper consists of three parts. In the first part we explain the concept of mental fictionalism. In the second part, we present the various versions of fictionalism and their main sources of motivation.We do this because in the third part we argue that mental fictionalism, as opposed to other versions of fictionalism, is a highly undermotivated theory.

Among fundamental metaphysical quests, one might wonder: Why is there anything at all rather than just nothing? Many reject that question because they think it is meaningless, trivial, or necessarily unanswerable. But I provide reasons for thinking that the Why question could make sense and one might even expect an answer to it. I begin by asking why the world is not empty of all concrete things. One might regard this question as important if one accepts that it is, in (...) some sense, possible for all concrete things to vanish, one-by-one. I argue finally that possible replies to the Why question concerning concrete things might point to realities that are abstract instead of concrete. Abstract realities might be explanatorily powerful without their power being guaranteed by Logic. (shrink)

This article discusses the argument we cannot have knowledge of abstract entities because they are not part of the causal order. The claim of this article is that the argument fails because of equivocation. Assume that the “causal order” is concerned with contingent facts involving time and space. Even if the existence of abstract entities is not contingent and does not involve time or space it does not follow that no truths about abstract entities are contingent or involve time or (...) space. I argue that it is the latter which is required to obtain the desired conclusion. (shrink)

In Modal Logic as Metaphysics, Timothy Williamson claims that the possibilism-actualism (P-A) distinction is badly muddled. In its place, he introduces a necessitism-contingentism (N-C) distinction that he claims is free of the confusions that purportedly plague the P-A distinction. In this paper I argue first that the P-A distinction, properly understood, is historically well-grounded and entirely coherent. I then look at the two arguments Williamson levels at the P-A distinction and find them wanting and show, moreover, that, when the N-C (...) distinction is broadened (as per Williamson himself) so as to enable necessitists to fend off contingentist objections, the P-A distinction can be faithfully reconstructed in terms of the N-C distinction. However, Williamson’s critique does point to a genuine shortcoming in the common formulation of the P-A distinction. I propose a new definition of the distinction in terms of essential properties that avoids this shortcoming. (shrink)

Recent work in the philosophy of mathematics has suggested that mathematical structuralism is not committed to a strong form of the Identity of Indiscernibles (II). José Bermúdez demurs, and argues that a strong form of II can be warranted on structuralist grounds by countenancing identity properties, or haecceities, as legitimately structural. Typically, structuralists dismiss such properties as obviously non-structural. I will argue to the contrary that haecceities can be viewed as structural but that this concession does not warrant Bermúdez’s version (...) of II but, rather, another easily falsified version. I close with some reflections on reference vis-à-vis structurally indiscernible objects. (shrink)

Actualism is the doctrine that the only things there are, that have being in any sense, are the things that actually exist. In particular, actualism eschews possibilism, the doctrine that there are merely possible objects. It is widely held that one cannot both be an actualist and at the same time take possible world semantics seriously — that is, take it as the basis for a genuine theory of truth for modal languages, or look to it for insight into the (...) modal structure of reality. For possible world semantics, it is supposed, commits one to possibilism. In this paper I take issue with this view. To the contrary, I argue that one can take possible world semantics seriously without any commitment to possible worlds or possibilism and hence remain in full compliance with actualist scruples. Moreover, one can do so without without invoking either "ersatz" worlds or haecceities. (shrink)

Possibilism—the view that there are non-actual, merely possible entities—is a surprisingly resilient doctrine.1 One particularly hardy strand of possibilism—the modal realism championed by David Lewis—continues to attract both foes who seek to demonstrate its falsity (or at least stare its advocates into apostasy) and friends who hope to defend modal realism (or, when necessary, modify modal realism so as to avoid problematic objections).2 Although I am neither a foe nor friend of modal realism (but some of my best friends are!), (...) like many I continue to be fascinated by the doctrine. (shrink)

Propositional contingentism is the view that what propositions there are is a contingent matter—certain propositions ontologically depend on objects which themselves only contingently exist. Possible worlds are, loosely, complete ways the world could have been. That is to say, the ways in which everything in its totality could have been. Propositional contingentists make use of possible worlds frequently. However, a neglected, but important, question concerns whether there are any notions of worlds which are both theoretically adequate and consistent with propositional (...) contingentism. Some notion of a possible world is adequate if the systematic connection between, at least, possibility and truth at some possible world holds. Here, I argue that no adequate notion of a possible world is available to at least those who subscribe to one natural formulation of propositional contingentism. I also show that this result contrasts with a simple and adequate definition of a possible world available to the necessitist—those who hold that necessarily everything necessarily exists. (shrink)

The simplest quantified modal logic combines classical quantification theory with the propositional modal logic K. The models of simple QML relativize predication to possible worlds and treat the quantifier as ranging over a single fixed domain of objects. But this simple QML has features that are objectionable to actualists. By contrast, Kripke-models, with their varying domains and restricted quantifiers, seem to eliminate these features. But in fact, Kripke-models also have features to which actualists object. Though these philosophers have introduced variations (...) on Kripke-models to eliminate their objectionable features, the most well-known variations all have difficulties of their own. The present authors reexamine simple QML and discover that, in addition to having a possibilist interpretation, it has an actualist interpretation as well. By introducing a new sort of existing abstract entity, the contingently nonconcrete, they show that the seeming drawbacks of the simplest QML are not drawbacks at all. Thus, simple QML is independent of certain metaphysical questions. (shrink)

According to strong pluralism, objects distinct by virtue of their modal properties can coincide. The most common objection towards such view invokes the so-called Grounding Problem according to which the strong pluralist needs to explain what the grounds are for supposed modal differences between the coincidents. As recognized in the literature, the failure to provide an answer to the Grounding Problem critically undermines the plausibility of strong pluralism. Moreover, there are strong reasons to believe that strong pluralists cannot provide an (...) explanation of the Grounding Problem. In this paper, we argue that strong pluralism can be motivated independently of the successful answer to the Grounding Problem. In order to achieve that aim, we provide a haecceitistic interpretation of strong pluralism according to which strong pluralism should be read as a position committed to the existence of primitive individuals, i.e., the individuals that have their criteria of individuation independently of their qualitative profiles. That said, we do not aim at defending haecceitism. Instead, our aim is rather modest: we want to provide a new way for the strong pluralist to supplement his view to make it more watertight. (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.

In a recent article, P. Roger Turner and Justin Capes argue that no one is, or ever was, even partly morally responsible for certain world-indexed truths. Here we present our reasons for thinking that their argument is unsound: It depends on the premise that possible worlds are maximally consistent states of affairs, which is, under plausible assumptions concerning states of affairs, demonstrably false. Our argument to show this is based on Bertrand Russell’s original ‘paradox of propositions’. We should then opt (...) for a different approach to explain world-indexed truths whose upshot is that we may be morally responsible for some of them. The result to the effect that there are no maximally consistent states of affairs is independently interesting though, since this notion motivates an account of the nature of possible worlds in the metaphysics of modality. We also register in this article, independently of our response to Turner and Capes, and in the spirit of Russell’s aforementioned paradox and many other versions thereof, a proof of the claim that there is no set of all true propositions one can render false. (shrink)