Inspired by the third chapter of Anselm's Proslogion, twentieth century philosophers including Charles Hartshorne and Alvin Plantinga developed “modal” ontological arguments for the existence of God. Such arguments use modal logic to infer God's existence from the premises that (i) God's existence is possible and (ii) if God exists, He exists necessarily. Like other ontological arguments, modal arguments have won few converts to theism; many commentators consider them question‐begging or liable to parody. This article details how recent (...) attempts to defend these arguments have tried to overcome these difficulties by drawing on modern accounts of the epistemology and metaphysics of modality. (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)

The modal ontological argument (MOA) proceeds from God’s possible existence to God’s actual existence. A prominent objection to the MOA is that it suffers from a symmetry problem: an exactly parallel modal ontological argument can be given for God's non-existence. Several attempts have been made to break the symmetry between the arguments. This draft is a mostly comprehensive survey of those attempts. -/- The draft was initially written as a supplement to the 2024 Summer edition of the SEP (...) entry on Ontological Arguments. However, the draft is not included in the SEP entry. (shrink)

Timothy Williamson has argued that in the debate on modal ontology, the familiar distinction between actualism and possibilism should be replaced by a distinction between positions he calls contingentism and necessitism. He has also argued in favor of necessitism, using results on quantified modal logic with plurally interpreted second-order quantifiers showing that necessitists can draw distinctions contingentists cannot draw. Some of these results are similar to well-known results on the relative expressivity of quantified modal logics with (...) so-called inner and outer quantifiers. The present paper deals with these issues in the context of quantified modal logics with generalized quantifiers. Its main aim is to establish two results for such a logic: Firstly, contingentists can draw the distinctions necessitists can draw if and only if the logic with inner quantifiers is at least as expressive as the logic with outer quantifiers, and necessitists can draw the distinctions contingentists can draw if and only if the logic with outer quantifiers is at least as expressive as the logic with inner quantifiers. Secondly, the former two items are the case if and only if all of the generalized quantifiers are first-order definable, and the latter two items are the case if and only if first-order logic with these generalized quantifiers relativizes. (shrink)

Our purpose in this paper is to delineate an ontology for quantum mechanics that results adequate to the formalism of the theory. We will restrict our aim to the search of an ontology that expresses the conceptual content of the recently proposed modal-Hamiltonian interpretation, according to which the domain referred to by non-relativistic quantum mechanics is an ontology of properties. The usual strategy in the literature has been to focus on only one of the interpretive problems (...) of the theory and to design an interpretation to solve it, leaving aside the remaining difficulties. On the contrary, our aim in the present work is to formulate a “global” solution, according to which different problems can be adequately tackled in terms of a single ontology populated of properties, in which systems are bundles of properties. In particular, we will conceive indistinguishability between bundles as a relation derived from indistinguishability between properties, and we will show that states, when operating on combinations of indistinguishable bundles, act as if they were symmetric with no need of a symmetrization postulate. (shrink)

In a recent paper in this journal, McIntosh ( 2021 ) argues that a modalized version of an epistemic principle of phenomenal conservativism can be used to successfully defend the key possibility premise of the modal ontological argument for the existence of God. I argue, however, that such a defense of the possibility premise is not going to be successful even if one concedes a number of contentious claims to McIntosh.

Our purpose in this paper is to delineate an ontology for quantum mechanics that results adequate to the formalism of the theory. We will restrict our aim to the search of an ontology that expresses the conceptual content of the recently proposed modal-Hamiltonian interpretation, according to which the domain referred to by non-relativistic quantum mechanics is an ontology of properties. The usual strategy in the literature has been to focus on only one of the interpretive problems (...) of the theory and to design an interpretation to solve it, leaving aside the remaining difficulties. On the contrary, our aim in the present work is to formulate a “global” solution, according to which different problems can be adequately tackled in terms of a single ontology populated of properties, in which systems are bundles of properties. In particular, we will conceive indistinguishability between bundles as a relation derived from indistinguishability between properties, and we will show that states, when operating on combinations of indistinguishable bundles, act as if they were symmetric with no need of a symmetrization postulate. (shrink)

The structure of the second, Or so-Called modal version of anselm's ontological argument is discussed in relation to various systems of alethic modal logic. It is argued that there are three current problems standing in the way of acceptance of the argument, Each related to its modal structure, And each an analogue of a traditional objection to anselm's original argument. Two of these problems can probably be solved, But the third remains recalcitrant.

We formulate a new modal ontological argument; specifically, we show that there is a possible world in which an entity that has at least the property of omnipotence exists. Then we argue that if such an entity is possible, it is necessary as well.

A course of dialogical reasoning involving the atheist and the theist reveals a connection between the Curry phenomenon and the step-wise construction of a sound version of the modal ontological argument. The exercise is both adversarial and cooperative as the participants are committed to the norms of shared truth-seeking, respect for one's opponents and a desire to continue the dialectic for as long as possible. The theist relies on the interaction between the properties of a Curry-style sentence and the (...) structure of implication in order to show that the atheist's own commitments imply Anselm's principle (God necessarily exists if He actually exists at all). As Anselm's principle and the possibility premise are the only assumptions required for the modal ontological argument it follows that the theist has, given the norms of the dialogue, a winning strategy against the atheist. This follows since the possibility premise is granted by the atheist as part of their commitment to the norms governing the dialectic though the theist in virtue of those same norms must accept that God is at best maximally perfect in the light of the argument from evil and the Stone paradox. (shrink)

This article shows that the modal ontological argument as proposed by Gottrieb Leibniz was very much anticipated in its logical articulation by John Duns Scotus in his work De Primo Principio. To this end, the author analyzes some of the various versions of the argument present in the philosophical thought of authors such as Scotus, Leibniz, Malcom and Plattinga, and demonstrates that those versions are based on the hidden premise of the possibility of the idea of God. In this (...) respect, the Spanish philosopher Gustavo Bueno defends what he calls an “inverted ontological argument” which, if viable, would prove not so much the non-existence of God but that the idea of God does not exist itself. (shrink)

This paper examines the so-called modal ontological argument. It pays special attention to the role that the symmetry and transitivity of the accessibility relation play in the argument, and examines various approaches to a defense of the “possibility premise,” the premise of the argument that states that the existence of a perfect being is metaphysically possible. It contains an analysis of Gödel’s attempt to show that this premise is true, and of a recent formulation by David Johnson of Gödel’s (...) argument. (shrink)

This paper is a critique of a paper by Alex Pruss. I argue that Pruss's attempt to motivate acceptance of the key possiblity premise in modal ontological arguments fails.

The problem of the relation and difference between things and objects is one of the most decisive issues for the conception of the real. These words are usually used interchangeably – and not only in their everyday usage. There are some contemporary philosophical positions that consider almost “everything” as an object; on the other hand, there are proponents of a strict separation of objects and things. How did it happen that the concept of thing (res) and object (obiectum) not only (...) began to theoretically “compete” with each other but also sometimes came to represent differently conceived realities, and even occasionally came to represent an identical conception of reality? This article, on the one hand, discusses the philosophical strategies that reveal the difference between objects and things and enable such a conception of reality which takes into account the Kantian distinction between Realität and Wirklichkeit. On the other, it reconstructs Giorgio Agamben’s project of modal ontology. Agamben’s take on the question What is real? is oriented toward the modus of being and could be traced back to the recognition of the difference between objects and things as well as the “restoration of the life of things themselves.”. (shrink)

In this paper we will argue that the ontology implicit in John Buridan’s modal octagon commits him to a form of contingentism. In particular, we will argue that Buridan is committed to denying the validity of the Barcan and converse Barcan formulae.

We use a mechanized verification system, PVS, to examine the argument from Anselm’s Proslogion Chapter III, the so-called “Modal Ontological Argument.” We consider several published formalizations for the argument and show they are all essentially similar. Furthermore, we show that the argument is trivial once the modal axioms are taken into account. This work is an illustration of Computational Philiosophy and, in addition, shows how these methods can help detect and rectify errors in modal reasoning.

ABSTRACTZambrano is well-known for her critique of the ideal subject, as well as of philosophy and ‘Western’ reason. Despite this critique, notions like the individual and reason in her works has not been thoroughly analysed. Enquist Källgren argues that Zambrano’s texts contains a comprehensive theory of subjectivity. It is shown that Zambrano’s notion of subjectivity presupposes a structure that positions the human being in a modal relation to her surroundings. The human being can be conceived of as a structure (...) of transcendent and transcendental positions in which the individual is the product of an expressive performativity. Zambrano’s theory of subjectivity can be read as an engagement with the thinking of both Aristotle and Kant, placing subjectivity in the tension between embodiment and transcendental capacities. It is concluded that Zambrano’s theory of subjectivity is in fact a modal ontology describing the condition of possibility of human existence. In addition, it is concluded that this modal ontology has important ethical implications since it presupposes the presence of an ‘other’ towards which expressive performativity is directed. (shrink)

Ontological dependence and grounding are two important items in the metaphysician’s toolbox: both notions can be used to formulate important philosophical claims and to define other notions that play a central role in philosophical theorising. Philosophical inquiry about ontological dependence and (especially) grounding has been very lively over the past few years, making it difficult to write a short review article on any of them, let alone a short review article on both. I try to reach a good compromise between (...) a discussion of each notion taken separately and a discussion of how they relate to one another. I begin by introducing the notions and discussing a number of their connections with modality (Sections 9.1 and 9.2), starting with grounding for systematic reasons (some important concepts of ontological dependence are defined in terms of grounding). I then further the discussion of how the notions are connected to each other, by arguing against the view that (partial) grounding is equivalent to (the converse of) ontological dependence between facts (Section 9.3). Finally, I discuss their respective roles in the theory of fundamentality (Section 9.4). (shrink)

This paper deals with some metaphilosophical aspects of the modal ontological argument originating from Charles Hartshorne. One of the specific premises of the argument expresses the idea that the existence of God is not contingent. Several well-known versions of the argument have been formulated that appeal to different ways of clarifying the latter. A question arises: which of the formally correct and relevant versions is proper or basic? The paper points to some criteria of formal correctness, and distinguishes two (...) types of relevance for these versions: strong and weak. Its aim is to furnish a strictly worked out answer to the question, taking into account each of these types. As a result, a very simple, formally correct and relevant version of the modal ontological argument is formulated. The results obtained are also used to criticize a popular belief about the relations in which the main versions of the modal ontological argument stand to one another. (shrink)

This book gathers together thirteen of Peter van Inwagen's essays on metaphysics, several of which have acquired the status of modern classics in their field. They range widely across such topics as Quine's philosophy of quantification, the ontology of fiction, the part-whole relation, the theory of 'temporal parts', and human knowledge of modal truths. In addition, van Inwagen considers the question as to whether the psychological continuity theory of personal identity is compatible with materialism, and defends the thesis (...) that possible states of affairs are abstract objects, in opposition to David Lewis's 'extreme modal realism'. A specially-written introduction completes the collection, which will be an invaluable resource for anyone interested in metaphysics. (shrink)

This article aims to provide a new ontological argument for the existence of God. A specific ‘modal’ version of the ontological argument—termed the Modal Realist Ontological Argument—is formulated within the modal realist metaphysical framework of David K. Lewis, Kris McDaniel and Philip Bricker. Formulating this argument within this specific framework will enable the plausibility of its central premise (i.e., the ‘Possibility Premise’) to be established, and allow one to affirm the soundness of the argument—whilst warding off two (...) oft-raised objections against this type of natural theological argument. (shrink)

The life-long correspondence of David K. Lewis, one of the most influential philosophers of the twentieth century, reveals the development, breadth, and depth of his philosophy in its historical context. The first of this two volume collection of letters focuses on his contributions to metaphysics, arguably where he made his greatest impact.

I set out and explore an argument for God's existence based on the idea that the possibility of God requires the existence of God as a ground. After setting this argument out, I compare it to other arguments for God, concentrating on an argument from Descartes's Third Meditation. I then address various objections and conclude by setting out a non-theistic version of the argument.

Computers may help us to better understand (not just verify) arguments. In this article we defend this claim by showcasing the application of a new, computer-assisted interpretive method to an exemplary natural-language ar- gument with strong ties to metaphysics and religion: E. J. Lowe’s modern variant of St. Anselm’s ontological argument for the existence of God. Our new method, which we call computational hermeneutics, has been particularly conceived for use in interactive-automated proof assistants. It aims at shedding light on the (...) meanings of words and sentences by framing their inferential role in a given argument. By employing automated theorem reasoning technology within interactive proof assistants, we are able to drastically reduce (by several orders of magnitude) the time needed to test the logical validity of an argu- ment’s formalization. As a result, a new approach to logical analysis, inspired by Donald Davidson’s account of radical interpretation, has been enabled. In computational hermeneutics, the utilization of automated reasoning tools ef- fectively boosts our capacity to expose the assumptions we indirectly commit ourselves to every time we engage in rational argumentation and it fosters the explicitation and revision of our concepts and commitments. (shrink)

Modal Platonism utilizes "weak" logical possibility, such that it is logically possible there are abstract entities, and logically possible there are none. Modal Platonism also utilizes a non-indexical actuality operator. Modal Platonism is the EASY WAY, neither reductionist nor eliminativist, but embracing the Platonistic language of abstract entities while eliminating ontological commitment to them. Statement of Modal Platonism. Any consistent statement B ontologically committed to abstract entities may be replaced by an empirically equivalent modalization, MOD(B), not (...) so ontologically committed. This equivalence is provable using Modal/Actuality Logic S5@. Let MAX be a strong set theory with individuals. Then the following Schematic Bombshell Result (SBR) can be shown: MAX logically yields [T is true if and only if MOD(T) is true], for scientific theories T. The proof utilizes Stephen Neale's clever model-theoretic interpretation of Quantified Lewis S5, which I extend to S5@. (shrink)

This is a book about the concept of a physical thing and about how the names of things relate to the things they name. It questions the prevalent view that names 'refer to' or 'denote' the things they name. Instead it presents a new theory of proper names, according to which names express certain special properties that the things they name exhibit. This theory leads to some important conclusions about whether things have any of their properties as a matter of (...) necessity. This will be an important book for philosophers in metaphysics and the philosophy of language, though it will also interest linguists concerned with the semantics of natural language. (shrink)

After introductory reminder of and comments on Gödel’s ontological proof, we discuss the collapse of modalities, which is provable in Gödel’s ontological system GO. We argue that Gödel’s texts confirm modal collapse as intended consequence of his ontological system. Further, we aim to show that modal collapse properly fits into Gödel’s philosophical views, especially into his ontology of separation and union of force and fact, as well as into his cosmological theory of the nonobjectivity of the lapse (...) of time. As a result, modal collapse should not be conceived in Gödel so much as a deficit, but rather as a kind of the rise of modalities to the “perfect” being. We further show that, in accordance with Gödel’s ontology, the concepts of modality and time should be derived in terms of the “fundamental philosophical concept” of cause. To give an example of how a formalization of such causative Gödelian ontology and ontological proof might look, we propose the transformation of GO into a kind of causally re-interpreted justification logic. (shrink)

This book explores a range of traditional and contemporary metaphysical themes that figure in the writings of E. J. Lowe, whose powerful and influential work was still developing at the time of his death in 2015. Leading philosophers present new essays on topics to do with ontology, necessity, existence, and mental causation.

This is a book about the concept of a physical thing and about how the names of things relate to the things they name. It questions the prevalent view that names 'refer to' or 'denote' the things they name. Instead it presents a new theory of proper names, according to which names express certain special properties that the things they name exhibit. This theory leads to some important conclusions about whether things have any of their properties as a matter of (...) necessity. This will be an important book for philosophers in metaphysics and the philosophy of language, though it will also interest linguists concerned with the semantics of natural language. (shrink)

Prominent thinkers such as Kripke and Rescher hold that Russell has no modal logic, even that Russell was indisposed toward modal logic. In Part I, I show that Russell had a modal logic which he repeatedly described and that Russell repeatedly endorsed Leibniz's multiplicity of possible worlds. In Part II, I describe Russell's theory as having three ontological levels. In Part III, I describe six Parmenidean theories of being Russell held, including: literal in 1903; universal in 1912; (...) timeless in 1914; transcendental in 1918–1948. The transcendental theory underlies the primary level of Russell's modal logic. In Part IV, I examine Rescher's view that Russell and modal logic did not mix. (shrink)

To be a realist about modality, need one claim that more exists than just the various objects and properties that populate the world—e.g. worlds other than the actual one, or maximal consistent sets of propositions? Or does the existence of objects and properties by itself involve the obtaining of necessities (and possibilities) in re? The latter position is now unpopular but not unfamiliar. Aristotle held that objects have essences, and hence necessarily have certain properties. Recently it has been argued that (...) the identity of any property is tied to the natural laws in which it figures, which entails that the occurrence of properties involves the obtaining of nomological necessities ([24], pp. 206-33 and 234-60; [23]; cf. [25] and [6]). Somewhat less recently, Wittgenstein ([28], p. 168) worried that the reality of at least some properties—precise shades of colors being a prime example—involved the obtaining in re of certain impossibilities. This paper argues that Wittgenstein’s worries were right, and not just concerning some properties, but all properties whatever. That there are objects and properties in the world at all, then, amounts to there obtaining modal states of affairs. This argument supplements, rather than replaces, the others. The position on property incompatibility advanced here actually helps defend Aristotelian essentialism against epistemological objections, or so I have argued ([15]). And while this paper’s position on property incompatibility diverges from the idea that a property’s nomic profile is essential to it—more on this in the next section—it is at least compatible with the thought that the necessity involved in the laws of nature enters into ontology at the ground level. (shrink)

The problem with model-theoretic modal semantics is that it provides only the formal beginnings of an account of the semantics of modal languages. In the case of non-modal language, we bridge the gap between semantics and mere model theory, by claiming that a sentence is true just in case it is true in an intended model. Truth in a model is given by the model theory, and an intended model is a model which has as domain the (...) actual objects of discourse, and which relates these objects in an appropriate manner. However, the same strategy applied to the modal case seems to require an intended modal model whose domain includes mere possibilia. Building on recent work by Christopher Menzel (Synthese 85 (1990)), I give an account of model-theoretic semantics for modal languages which does not require mere possibilia or intensional entities of any kind. Menzel has offered a representational account of model-theoretic modal semantics that accords with actualist scruples, since it does not require possibilia. However, Menzel's view is in the company of other actualists who seek to eliminate possible worlds, but whose accounts tolerate other sorts of abstract, intensional entities, such as possible states of affairs. Menzel's account crucially depends on the existence of properties and relations in intension. I offer a purely extensional, representational account and prove that it does all the work that Menzel's account does. The result of this endeavor is an account of model theoretic semantics for modal languages requiring nothing but pure sets and the actual objects of discourse. Since ontologically beyond what is prima facie presupposed by the model theory itself. Thus, the result is truly an ontology-free model-theoretic semantics for modal languages. That is to say, getting genuine modal semantics out of the model theory is ontologically cost-free. Since my extensional account is demonstrably no less adequate, and yet is at the same time more ontologically frugal, it is certainly to be preferred. (shrink)

In the paper we introduce a wide range of Anderson-like variants of Gödel's theory and prove for each of them strong completeness theorem wrt. corresponding class of modal structures.These theories — all formulated in the 2nd order modal language with a 2nd order unary predicate of positiveness — differ among themselves with respect of: properties of the necessity operator and of the predicate of positiveness, axioms characterizing identity between 1st sort terms, definitions of identity between 2nd sort terms, (...) the treatment of Godlikeness as a term of the 2nd order, the treatment of necessary existence as a term of the 2nd order if there exists the necessity of its presence, the treatment of Ix (Ix(y) is read: terms x, y are identical), for every 1st sort term x, as a term of the 2nd order if there exists the necessity of its presence.Concerning to semantical commitments, the following are essential: (i) 1st order terms order receive only rigid extensions in the constant objectual 1st order domain; (ii) 2nd order terms receive non-rigid extensions in the constant objectual domain of 2nd order and rigid intensions in the constant conceptual 2nd order domain; (iii) The behavior of the identity between 1st sort terms shifts from possible worlds to possible worlds. (shrink)

This article aims to provide a new ontological argument for the existence of God. A specific ‘modal’ version of the ontological argument—termed the Modal Realist Ontological Argument—is formulated within the modal realist metaphysical framework of David K. Lewis, Kris McDaniel and Philip Bricker. Formulating this argument within this specific framework will enable the plausibility of its central premise (i.e., the ‘Possibility Premise’) to be established, and allow one to affirm the soundness of the argument—whilst warding off two (...) oft-raised objections against this type of natural theological argument. (shrink)

In this paper we show how modal logic can be applied in the axiomatizations of some dynamic ontologies. As an example we consider the case of mereotopology, which is an extension of mereology with some relations of topological nature like contact relation. We show that in the modal extension of mereotopology we may define some new mereological and mereotopological relations with dynamic nature like stable part-of and stable contact. In some sense such “stable” relations can be considered as (...) approximations of the “essential relations” in the domain of mereotopology. (shrink)

Modal constitution theory is one of the most influential solutions to the paradoxes of coincidence, and the problem of personal identity. It rests on three fundamental premises: common-sense objects exist; sometimes objects coincide in space; the coincidence of objects in space requires explanation. In this article, the author offers a critique of the modal theory of constitution. First, the definition of the constitution is examined and a new argument is offered that modal theory either does not provide (...) asymmetry of the constitution or leads to an infinite series of constitutive objects, unsatisfactorily extending ontology. Also, the author demonstrates that possible additions to the constitutive definition, which can make the definition sufficient for asymmetric relation, lead to additional theoretical difficulties, leading to the logical impossibility of constitution relation. Second, the author demonstrates that the theory of constitution offers an unsatisfactory theory of identity because it faces three problems: the overpopulation problem, the epistemic problem, and the personal problem. All of these considerations lead the author to conclude that modal constitution theory is not metaphysically satisfactory. (shrink)

This study in fundamental ontology calls for rethinking some pedestrian assumptions about what there is and provides the motivation for a new theory of reference. It contains clear, crisp discussions of mereology, identity, reference, and necessity and should be valuable to metaphysicians and philosophers of language.

This is the second in a sequence of three essays which axiomatize and apply Edmund Husserl's dependence ontology of parts and wholes as a non-Diodorean, non-Kantian temporal semantics for first-order predicate modal languages. The Ontology of Intentionality I introduced enough of Husserl's dependence-ontology of parts and wholes to formulate his account of order as effected by relating moments of unity, and The Ontology of Intentionality II extends that axiomatic dependence-ontology far enough to enable its (...) semantic application. Formalizing the compatibility [Vereinbarkeit] relation implicated in Husserl's notorious doctrine of impossible meanings, the essay introduces a compatibility restriction on relations to formulate Husserl's distinction between singular [einheitliche] and plural [mehrheitliche] objects, using plural relating moments to define first-order versions of Husserl's notions of relation complexes (i.e. Sachverhalte), abstracta of n-ary relation complexes, categorial relations, abstract eide as unifications of categorial relations, semantic domains as completions of abstract eide, and material regions as semantic domains which are compatibility upper bounds of categorial relations. These concepts will enable the formal dependence-ontological noetic semantics for two-valued, first-order modal languages introduced in the sequel Two-Valued Logics of Intentionality, the third essay in the sequence. (shrink)

What is the relationship between ontology and modality - between what there is, and what there could be, must be, or might have been? Bob Hale interwove these two strands of metaphysics throughout his long and distinguished career, putting forward his theses in his book, Necessary Beings: An Essay on Ontology, Modality, and the Relations Between Them (OUP 2013). Hale addressed questions of ontology and modality on a number of fronts: through the development of a Fregean approach (...) to ontology, an essentialist theory of modality, and in his work on neo-logicism in the philosophy of mathematics. The essays in this volume engage with these themes in Hale's work in order to progress our understanding of ontology, modality, and the relations between them. Some directly address questions in modal metaphysics, drawing on ontological concerns, while others raise questions in modal epistemology and of its links to matters of ontology, such as the challenge to give an epistemology of essence. Several essays also engage with questions of what might be called 'modal ontology': the study of whether and what things exist necessarily or contingently. Such issues have an important bearing on the kinds of semantic commitments engendered in logic and mathematics (to the existence of sets, or numbers, or properties, and so on) and the extent to which one's ontology of necessary beings interacts with other plausible assumptions and commitments. (shrink)

Edited by Ivette Fred-Rivera and Jessica Leech. What is the relationship between ontology and modality: between what there is, and what there could be, must be, or might have been? Throughout a distinguished career, Bob Hale’s work has addressed this question on a number of fronts, through the development of a Fregean approach to ontology, an essentialist theory of modality, and in his work on neo-logicism in the philosophy of mathematics. This collection of new essays engages with these (...) themes in Hale’s work in order to make further progress in our understanding of ontology, modality, and the relations between them. Some essays directly address questions in modal metaphysics, drawing on ontological concerns. Others raise questions in modal epistemology and its links to matters of ontology, such as the challenge to give an epistemology of essence. There are also several essays engaging with questions of what might be called ‘modal ontology’: the study of whether and what things exist necessarily or contingently. Such issues can be raised and addressed directly, but they also have an important bearing on the kinds of semantic commitments engendered in logic and mathematics, e.g., to the existence of sets, or numbers, or properties, and so on. It is thus explored in some chapters to what extent one’s ontology—and indeed, one’s ontology of necessary beings—interacts with other plausible assumptions and commitments. (shrink)

A simple argument against Lewisian modal realism as portrayed in On the Plurality of World arises from its treatment of doxastic modalities. It is easily shown that if it is true, it is impossible to doubt the theory on ontological grounds, or, that, if it is possible to maintain doubt about modal realism’s existential postulate, it has to be false. The argument hinges on the fact that modal realism’s main ontological hypothesis, if true, is necessarily true.

This paper discusses a range of modal ontological arguments. It is claimed that these modal ontological arguments fail because they depend upon controversial assumptions about the nature of modal space.

Most relational theories assert both that spatial discourse is reducible to talk about physical objects and their spatial relations, and that the relation of congruence derives from a non-metrical relation which intervals bear or possibly bear to measuring instruments. We have shown that there are serious logical difficulties involved in maintaining both these positions and the thesis of the continuity of space. We have also shown that Grünbaum's motivating argument for the reduction of congruence is unsound, and, moreover, that the (...) prospects of formulating the kind of definition which this reduction requires seem to rest upon a wholly vague notion of physical possibility. Alternatively, if congruence is taken as primitive, it seems plausible that spatial discourse can be reconstructed so that there is no ontological commitment to spatial objects other than physical objects. Whether or not this relational thesis is ultimately defensible requires more elaboration of the relational theory, and investigation of its role in the formalizations of current physical theories. It is odd, considering the wide currency of relational theories, that this work has never been done. (shrink)

There are two types of theories regarding many worlds: one is modal, while the other is temporal. The former regards reality as consisting of many possible worlds, while the latter holds that reality consists of many momentary worlds, which are usually called moments. I compare these two theories, paying close attention to the concept of transworld identity and compare trans-possible world identity with trans-momentary world identity (or transmoment identity). I characterize time from the point of many-worlds view, believing this (...) to be one of the best ways of grasping the reality of time. First, I show that there is reason to adopt the many-worlds view because transworld identity is meaningful for both of them, while it is not for space. Second, I argue that transmoment identity is different from transpossible world identity concerning reality. The former is a realistic relation, while the latter is not. Thus, I find that the reality of time is in the relation of transmoment identity. Such a view, I contend, has merit on the basis that it recognizes the reality of time in a sense that is not true of space. (shrink)

This paper is concerned with the wholly metaphysical question of whether necessity and possibility rest on nonmodal foundations—whether the truth conditions for modal statements are, in the final analysis, nonmodal. It is argued that Lewis’s modal realism is either arbitrary and stipulative or else it is circular. Even if there were Lewisean possible worlds, they could not provide the grounds for modality. D. M. Armstrong’s combinatorial approach to possibility suffers from similar defects. Since more traditional reductions to cognitive (...) or linguistic facts suffer similar fates, the conclusion that the alethic modality is primitive and incapable of reduction is offered. (shrink)