Theories of Modality, Misc

Despite the notions of possible worlds and substances are very important subjects of contemporary metaphysics, there are relatively few attempts to combine these in a united framework. This paper considers the metaphysical model of the origins and the evolution of possible worlds that occurs from an interaction between substances. I involve Leibniz’s doctrine of the striving possibles that every possibility of substance has its own essence and tendency towards existence. It is supposed that the activities of substances are constantly aimed (...) at using this tendency in all possible ways. Only the consistent and stable interactions between the substances give birth to stable objects in one of many worlds. Thus activity of substances changes from the possible modality of being to the actual modality of being in form of existence of the worlds. I divide substance’s possibility into two aspects—dynamic (possible or virtual history) and static (possible or potential mutual state). Thanks to the summation of virtual histories, in the possible modality of being, the maximal number of virtual histories is combined into the actual history in the actual modality. (shrink)

In this article, we discuss a simple argument that modal metaphysics is misconceived, and responses to it. Unlike Quine’s, this argument begins with the banal observation that there are different candidate interpretations of the predicate ‘could have been the case’. This is analogous to the observation that there are different candidate interpretations of the predicate ‘is a member of’. The argument then infers that the search for metaphysical necessities is misguided in much the way the ‘set-theoretic pluralist’ (Clarke-Doane & Hamkins (...) [2017]) claims that the search for the true axioms of set theory is. We show that the obvious responses to this argument fail. However, a new response has emerged that purports to prove, from higher order logical principles, that metaphysical possibility is the broadest kind of possibility applying to propositions, and is to that extent special. We distill two lines of reasoning from the literature, and argue that their import depends on premises that a ‘modal pluralist’ should deny. Both presuppose that there is a unique typed hierarchy, which is what the modal pluralist, in the context of higher-order logic, should disavow. In other words, both presupposes that there is a unique candidate for what higher-order claims could mean. We consider the worry that, in a higher-order setting, modal pluralism faces an insuperable problem of articulation, collapses into modal monism, is vulnerable to the Russell-Myhill paradox, or even contravenes the truism that there is a unique actual world, and argue that these worries are misplaced. We also sketch the bearing of the resulting ‘Higher Order Pluralism’ on the theory of content. One upshot is that, if Higher Order Pluralism is true, then there is no fixed metatheory from which to characterize higher order reality. (shrink)

In a recent article forthcoming in *Mind*, Leech (2020) presents a challenge for essentialist accounts of metaphysical modality: why should it be that essences imply corresponding necessities? Leech’s main focus is to argue that one cannot overcome the challenge by utilizing an account of essence in terms of generalized identity due to Correia and Skiles (2019), on pain of circularity. In this reply, we will show how to use identity-based essentialism to bridge ‘epistemic’ and ‘explanatory’ understandings of this alleged essence-to-necessity (...) gap without circularity, Leech’s arguments notwithstanding. We do so by first presenting a novel proof that generalized identities imply corresponding necessities. We then propose several substantive identity-based explanations of how it is, exactly, that essences imply necessities. -/- . (shrink)

There is a tension between Dispositionalism –– the view that all metaphysical modality is grounded in actual irreducible dispositional properties –– and the possibility of time travel. This is due to the fact that Dispositionalism makes it much harder to solve a potentiality-based version of the grandfather paradox. We first present a potentiality-based version of the grandfather paradox, stating that the following theses are inconsistent: 1) time travel is possible, 2) powers fully ground modality, 3) self-defeating actions are impossible, 4) (...) time-travellers retain their intrinsic powers upon time-travelling, and 5) time-travellers are ordinary agents with basic intrinsic potentialities. We then consider a number of potential solutions, and find them wanting. We argue that the metaphysical impossibility of performing a self-defeating action acts as a necessary perfect mask –– while time-travel lets us “slip” the potentiality under the mask, thus generating the contradiction. We conclude considering what are the options for the dispositionalist. (shrink)

Essentialists hold that at least a certain range of entities can be meaningfully said to have natures, essences, or essential features independently of how these entities are described, conceptualized or otherwise placed with respect to our specifically human interests, purposes or activities. Modalists about essence, on the one hand, take the position that the essential truths are a subset of the necessary truths and the essential properties of entities are included among their necessary properties. Non-modalists about essence, on the other (...) hand, oppose the reduction of essence to modality and hold, rather, that essence is more basic than, and explanatory of, modality. This chapter begins with a brief summary of Kit Fine’s well-known challenges to the modal account of essence and considers a recent attempt by “sparse modalists” like Sam Cowling and Nathan Wildman to respond to Fine’s counterexamples by adding a sparseness constraint to the “bare” modal account of essence. A further question arises, however, as to whether and how Fine’s definitional approach can avoid his own counterexamples against the modal approach to essence. The chapter concludes with some final thoughts concerning the theoretical roles ascribed to essence by modalists and non-modalists. (shrink)

Aristotle's concern with essence and definition, as central to the subject-matter of metaphysics, is shared by contemporary neo-Aristotelian philosophers. For E. J. Lowe metaphysics is an a priori inquiry that is “perhaps most perspicuously characterized as the science of essence” (Lowe (2008), p. 34). Kit Fine holds that “the concept [of essence] may be used to characterize what the subject [of metaphysics], or at least part of it, is about” (Fine (1994), p. 1). But whether metaphysics, and metaphysics alone, can (...) be tasked with the study of essence and by what methods this inquiry proceeds depends crucially on how the proposed non-modalist program of explaining metaphysical modality in terms of essence is carried out. This paper investigates a number of important questions which remain open in this area; how these questions are resolved crucially affects one’s conception of metaphysics as a discipline and its connection to the study of essence. (shrink)

Modal dispositionalists hold that dispositions provide the foundation of metaphysical necessity and possibility. According to the kind of modal dispositionalism that can be found in the present literature, a proposition p is possible just in case some things are disposed to be such that p. In the first part of this paper I show that combining this classic form of dispositionalism with the assumptions that the laws of nature are necessary and deterministic and that all dispositions are forward-looking in time (...) leads to the unattractive conclusion that every truth is necessary. I argue that the classic dispositionalist should be troubled by this result and in the second part of the paper I suggest a novel variant of dispositionalism that avoids it. This extended form of dispositionalism allows that some propositions are only indirectly underwritten by dispositions. (shrink)

Establishing Dispositionalism as a viable theory of modality requires the successful fulfilment of two tasks: showing that all modal truths can be derived from truths about actual powers, and offering a suitable metaphysics of powers. These two tasks are intertwined: difficulties in one can affect the chances of success in the other. In this paper, I generalise an objection to Dispositionalism by Jessica Leech and argue that the theory in its present form is ill-suited to account for de re truths (...) about merely possible entities. I argue that such difficulty is rooted in a problem in the metaphysics of powers. In particular, I contend that the well-known tension between two key principle of powers ontology, namely Directedness and Independence has received an unsatisfactory solution so far, and that it is this unsatisfactory solution concerning the status of “unmanifested manifestations” that makes it hard for Dispositionalism to account for mere possibilia. I develop a novel account of the status of unmanifested manifestations and an overall metaphysics of powers which allows to better respond to Leech's objection and handle mere possibilia. The central idea of the proposal is that unmanifested manifestations are akin to mere logical existents, and are best characterised as non-essentially non-located entities. (shrink)

General consensus has it that contingencies lack the requisite modal umph to serve as explanations for the modal status of necessities. The central aim of this paper is to show that this received opinion is incorrect: contingent necessity-makers are in fact possible. To do so, I identify certain conditions the satisfaction of which entail the possibility of contingent necessity-makers. I then argue for two broad instances where these conditions are satisfied. Consequently, the associated necessities in fact have contingent necessity-makers.

My topic in this paper is the relationships of metaphysical priority which might hold between the different alethic modal statuses—necessity, contingency, possibility and impossibility. In particular, I am interested in exploring the view that the necessity of necessities is ungrounded while the contingency of contingencies is grounded—a scenario I call ‘necessity first’. I will explicate and scrutinize the contrast between necessity first and its ‘contingency first’ contrary, and then compare both views with ‘multimodal’ and ‘amodal’ alternatives, drawing on David Lewis’s (...) modal realism and Barbara Vetter’s potentialism as example cases. I will then defend the necessity-first point of view from a reversed version of Blackburn’s classic dilemma against theories of the source of necessity. (shrink)

Rani Lill Anjum and Stephen Mumford have recently defended a new kind of modality, which they call ‘dispositional modality’. The key reason to adopt dispositional modality, according to them, is that causes never necessitate their effects. Anjum and Mumford’s chief argument against causal necessitation makes use of what they call the ‘antecedent-strengthening test’ : C causally necessitates E iff C & φ causes E, for any possible φ. This test, they claim, fails in all cases of alleged causal necessitation. In (...) this paper we argue that the AS-test is not the mark of causal necessitation. First, we show that if the AS-test is taken as the mark of causal necessitation it leads to either an absurdity or to circularity. Second, we argue that, given the Mill/Mackie framework of causes as INUS conditions, apparent counterexamples to causal necessitation fail. (shrink)

⦿ In my dissertation I introduce, motivate and take the first steps in the realization of, the project of naturalising modal metaphysics: the transformation of the field into a chapter of the philosophy of science rather than speculative, autonomous metaphysics. ⦿ In the introduction, I explain the concept of naturalisation that I apply throughout the dissertation, which I argue to be an improvement on Ladyman and Ross' proposal for naturalised metaphysics. I also object to Williamson's proposal that modal metaphysics --- (...) or some view in the area --- is already a quasi-scientific discipline. ⦿ Recently, some philosophers have argued that the notion of metaphysical modality is as ill defined as to be of little theoretical utility. In the second chapter I intend to contribute to such skepticism. First, I observe that each of the proposed marks of the concept, except for factivity, is highly controversial; thus, its logical structure is deeply obscure. With the failure of the "first principles" approach, I examine the paradigmatic intended applications of the concept, and argue that each makes it a device for a very specific and controversial project: a device, therefore, for which a naturalist will find no use for. I conclude that there is no well-defined or theoretically useful notion of objective necessity other than logical or physical necessity, and I suggest that naturalising modal metaphysics can provide more stable methodological foundations. ⦿ In the third chapter I answer a possible objection against the in-principle viability of the project: that the concept of metaphysical modality cannot be understood through the philosophical analysis of any scientific theory, since metaphysical necessity "transcends'' natural necessity, and science only deals with the latter. I argue that the most important arguments for this transcendence thesis fail or face problems that, as of today, remain unsolved. ⦿ Call the idea that science doesn't need modality, "demodalism''. Demodalism is a first step in a naturalistic argument for modal antirealism. In the fourth chapter I examine six versions of demodalism to explain why a family of formalisms, that I call "spaces of possibility'', are (i) used in a quasi-ubiquitous way in mathematised sciences (I provide examples from theoretical computer science to microeconomics), (ii) scientifically interpreted in modal terms, and (iii) used for at least six important tasks: (1) defining laws and theories; (2) defining important concepts from different sciences (I give several examples); (3) making essential classifications; (4) providing different types of explanations; (5) providing the connection between theory and statistics, and (6) understanding the transition between a theory and its successor (as is the case with quantisation). ⦿ In fifth chapter I propose and defend a naturalised modal ontology. This is a realism about modal structure: my realism about constraints. The modal structure of a system are the relationships between its possible states and between its possible states and those of other systems. It is given by the plurality of restrictions to which said system is subject. A constraint is a factor that explains the impossibility of a class of states; I explain this concept further. First, I defend my point of view by rejecting some of its main rivals: constructive empiricism, Humean conventionalism, and wave function realism, as they fail to make sense of quantum chaos. This is because the field requires the notion of objective modal structure, and the mentioned views have trouble explaining the modal facts of quantum dynamics. Then, I argue that constraint realism supersedes these views in the context of Bohm's standard theory and mechanics, and underpins the study of quantum chaos. Finally, I consider and reject two possible problems for my point of view. ⦿ A central concern of modal metaphysicians has been to understand the logical system that best characterises necessity. In the sixth chapter I intend to recover the logical project applied to my naturalistic modal metaphysics. Scientists and philosophers of science accept different degrees of physical necessity, ranging from purely mathematically necessary facts that restrict physical behaviour, to kinetic principles, to particular dynamical constraints. I argue that this motivates a multimodal approach to modal logic, and that the time dependence of dynamics motivates a logic of historical necessity. I propose multimodal propositional (classical) logics for Bohmian mechanics and the Everettian theory of many divergent worlds, and I close with a criticism of Williamson's approach to the logic of state spaces of dynamic systems. (shrink)

Within philosophy, the word “possible” is generally used to speak about either of the following. (1) Possibility: the notion that is expressed by sentences such as “It is possible that there are green cats,” “She may become the best surgeon in the city,” and “Our team can win the race.” Among the features of possibility, three are of particular interest to philosophers: it is closely related with necessity, contingency, and actuality; it is not unified, but comes in multiple varieties; it (...) is intuitively linked to conceivability. (2) The possible: the target of sentences expressing a possibility, i.e., whatever is possible. Philosophical inquiry is notably interested in the existence and the nature of possible things. For those who think possible things exist, the challenge is to say how and where. For those who think possible things do not exist, the challenge is to say how sentences stating a possibility can be true. (shrink)

According to essentialism, metaphysical modality is founded in the essences of things, where the essence of a thing is roughly akin to its real definition. According to potentialism (also known as dispositionalism), metaphysical modality is founded in the potentialities of things, where a potentiality is roughly the generalized notion of a disposition. Essentialism and potentialism have much in common, but little has been written about their relation to each other. The aim of this paper is to understand better the relations (...) between essence and potentiality, on the one hand, and between essentialism and potentialism, on the other. It is argued, first, that essence and potentiality are not duals but interestingly linked by a weaker relation dubbed ‘semi-duality’; second, that given this weaker relation, essentialism and potentialism are not natural allies but rather natural competitors; and third, that the semi-duality of essence and potentiality allows the potentialist to respond to an important explanatory challenge by using essentialist resources without thereby committing to essentialism. (shrink)

Trevor Teitel (2017) has recently argued that combining the assumption that modality reduces to essence with the assumption that possibly some objects contingently exist leads to problems if one wishes to uphold that the logic of metaphysical modality is S5. In this paper I will argue that there is a way for the essentialist to evade the problem described by Teitel. The proposed solution crucially involves the assumption that some propositions possibly fail to exist. I will show how this assumption (...) affords a motivated contingentist response to Teitel’s argument. (shrink)

The principle of plenitude says that every material object coincides with abundantly many further objects that differ in their modal profiles. A necessarily unmanifested disposition is a disposition that necessarily does not manifest. This paper argues that if the principle of plenitude holds, then there are some necessarily unmanifested dispositions. These necessarily unmanifested dispositions will be argued to evade some objections against the cases of necessarily unmanifested dispositions put forward by Carrie Jenkins and Daniel Nolan.

William L. Rowe poses a dilemma between God’s freedom and essential moral goodness by arguing that God cannot satisfy the arguably accepted condition for libertarian freedom, namely, ability to do otherwise. Accordingly, if God does a morally good action A freely, then there is at least a possible world in which God refrains from doing A and thereby does the morally wrong action. And if God does a morally wrong action in one of the possible worlds, he ceases to be (...) essentially morally perfect. I will argue that Rowe’s conclusion is based on a specific possible world semantics, and we might avoid Rowe’s conclusion with an alternative understanding of modality. In doing so, I will examine the conception of modality proposed by al-Ghaza ̄l ̄ı in which the possibility of a state of affairs does not entail its actuality in at least one possible world. (shrink)

Drawing from extensions of existing ideas in the logic of ground, a novel account of the grounds of necessity is presented, the core of which states that necessary truths are necessary because they stand in specific grounding connections.

This paper aims to build a bridge between two areas of philosophical research, the structure of kinds and metaphysical modality. Our central thesis is that kinds typically involve super-explanatory properties, and that these properties are therefore metaphysically essential to natural kinds. Philosophers of science who work on kinds tend to emphasize their complexity, and are generally resistant to any suggestion that they have “essences”. The complexities are real enough, but they should not be allowed to obscure the way that kinds (...) are typically unified by certain core properties. We shall show how this unifying role offers a natural account of why certain properties are metaphysically essential to kinds. (shrink)

The paper sketches an argument against modal monism, more specifically against the reduction of physical possibility to metaphysical possibility. The argument is based on the non-categoricity of quantum logic.

This paper responds to the contributions by Alexander Bird, Nathan Wildman, David Yates, Jennifer McKitrick, Giacomo Giannini & Matthew Tugby, and Jennifer Wang. I react to their comments on my 2015 book Potentiality: From Dispositions to Modality, and in doing so expands on some of the arguments and ideas of the book.

As Vetter says, we are at the “beginning of the debate, not the end” (2015: 300) when it comes to evaluating her potentiality-based account of metaphysical modality. This paper contributes to this developing debate by highlighting three problems for Vetter’s account. Specifically, I begin (§1) by articulating some relevant details of Vetter’s potentiality-based view. This leads to the first issue (§2), concerning unclarity in the idea of degrees of potentiality. Similarly, the second issue (§3) raises trouble for Vetter’s proposed individuation (...) conditions for potentialities. Finally, the third issue (§4) is about apparently unmanifestable intrinsic potentialities, and suggests that there might be some deeper problems with anchoring metaphysical possibilities in concrete objects. More generally, though the issues detailed here are problematic, I do not take them to be fatal. However, they do show that, at minimum, further clarification of Vetter’s potentiality view is required. As Vetter says, we are at the “beginning of the debate, not the end” (2015: 300) when it comes to evaluating her potentiality-based account of metaphysical modality. This paper contributes to this developing debate by highlighting three problems for Vetter’s account. Specifically, I begin (§1) by articulating some relevant details of Vetter’s potentiality-based view. This leads to the first issue (§2), concerning unclarity in the idea of degrees of potentiality. Similarly, the second issue (§3) raises trouble for Vetter’s proposed individuation conditions for potentialities. Finally, the third issue (§4) is about apparently unmanifestable intrinsic potentialities, and suggests that there might be some deeper problems with anchoring metaphysical possibilities in concrete objects. More generally, though the issues detailed here are problematic, I do not take them to be fatal. However, they do show that, at minimum, further clarification of Vetter’s potentiality view is required. (shrink)

According to dispositionalism about modality, a proposition <p> is possible just in case something has, or some things have, a power or disposition for its truth; and <p> is necessary just in case nothing has a power for its falsity. But are there enough powers to go around? In Yates (2015) I argued that in the case of mathematical truths such as <2+2=4>, nothing has the power to bring about their falsity or their truth, which means they come out both (...) necessary and not possible. Combining this with axiom (T), it is easy to derive a contradiction. I suggested that dispositionalists ought to retreat a little and say that <p> is possible just in case either p, or there is a power to bring it about that p, grounding the possibility of mathematical propositions in their truth rather than in powers. Vetter’s (2015) has the resources to provide a response to my argument, and in her (2018) she explicitly addresses it by arguing for a plenitude of powers, based on the idea that dispositions come in degrees, with necessary properties a limiting case of dispositionality. On this view there is a power for <2+2=4>, without there being a power to bring about its truth. In this paper I argue that Vetter’s case for plenitude does not work. However, I suggest, if we are prepared to accept metaphysical causation, a case can be made that there is indeed a power for <2+2=4>. (shrink)

It is widely alleged that metaphysical possibility is “absolute” possibility Conceivability and possibility, Clarendon, Oxford, 2002, p 16; Stalnaker, in: Stalnaker Ways a world might be: metaphysical and anti-metaphysical essays, Oxford University Press, Oxford, 2003, pp 201–215; Williamson in Can J Philos 46:453–492, 2016). Kripke calls metaphysical necessity “necessity in the highest degree”. Van Inwagen claims that if P is metaphysically possible, then it is possible “tout court. Possible simpliciter. Possible period…. possib without qualification.” And Stalnaker writes, “we can agree (...) with Frank Jackson, David Chalmers, Saul Kripke, David Lewis, and most others who allow themselves to talk about possible worlds at all, that metaphysical necessity is necessity in the widest sense.” What exactly does the thesis that metaphysical possibility is absolute amount to? Is it true? In this article, I argue that, assuming that the thesis is not merely terminological, and lacking in any metaphysical interest, it is an article of faith. I conclude with the suggestion that metaphysical possibility may lack the metaphysical significance that is widely attributed to it. (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)

I motivate and develop a view, found in John Duns Scotus, concerning God's explanatory role in the possibility of possible natures. A possible nature is a nature which can be instanced. The view is that possible natures have their possibility due to the coherence of their simple parts, but the simples which make up natures are themselves ex nihilo productions of divine intellect.

One’s involvement with the world seems limited merely to things as they are; hence, modal knowledge—knowledge of what could be or must be simpliciter—should be perplexing. Traditionally, the notion of conceivability has been regarded as crucial to an account of modal knowledge. I believe one has a good deal of such knowledge (though perhaps less than others presume one has). I maintain, however, that conceiving is utterly idle in acquiring modal knowledge: the conceivability of a proposition can provide no evidence (...) whatsoever that what it represents is possible. To show this, I first examine the basis of modal knowledge. I consider what conceivability in general is supposed to be and argue, in light of the preceding considerations, that conceivability is not epistemically efficacious, in the sense of providing evidence, on any proposed specific account. I then maintain that there could be no account of conceivability on which it is epistemically efficacious, that the very idea of the conceivability of a proposition being evidential is misguided. I conclude with some brief recommendations for pursuing a satisfactory modal epistemology. (shrink)

Bundle theories identify material objects with bundles of properties. On the traditional approach, these are the properties possessed by that material object. That view faces a deep problem: it seems to say that all of an object’s properties are essential to it. Essential bundle theory attempts to overcome this objection, by taking the bundle as a specification of the object’s essential properties only. In this paper, I show that essential bundle theory faces a variant of the objection. To avoid the (...) problem, the theory must accept the contingency of identity. I show how this can be achieved in a coherent and well-motivated way, a way that isn’t available to traditional bundle theories. (shrink)

The paper provides a review of the collection of scientific works «Williamson on Modality» and contains a brief summary of the main ideas of the articles published in the book.

This essay argues that, with his much-maligned “infinite analysis” theory of contingency, Leibniz is onto something deep and important – a tangle of issues that wouldn’t be sorted out properly for centuries to come, and then only by some of the greatest minds of the twentieth century. The first two sections place Leibniz’s theory in its proper historical context and draw a distinction between Leibniz’s logical and meta-logical discoveries. The third section argues that Leibniz’s logical insights initially make his “infinite (...) analysis” theory of contingency more rather than less perplexing. The last two sections argue that Leibniz’s meta-logical insights, however, point the way towards a better appreciation of (what we should regard as) his formal theory of contingency, and its correlative, his formal theory of necessity. (shrink)

Possible worlds semantics faces a range of difficulties for at least certain types of modals, especially deontic modals with their distinction between heavy and light permissions and obligations. This paper outlines a new semantics of modals that aims to overcome some of those difficulties. The semantics is based on an a novel ontology of modal objects, entities like obligations, permissions, needs, as well as epistemic states, abilities, and essences. Moreover, it is based on truthmaking, in the sense of Fine’s recent (...) truthmaker semantics. (shrink)

A series of recent studies have explored the impact of people's judgments regarding physical law, morality, and probability. Surprisingly, such studies indicate that these three apparently unrelated types of judgments often have precisely the same impact. We argue that these findings provide evidence for a more general hypothesis about the kind of cognition people use to think about possibilities. Specifically, we suggest that this aspect of people's cognition is best understood using an idea developed within work in the formal semantics (...) tradition, namely the notion of modality. On the view we propose, people may have separate representations for physical, moral and probabilistic considerations, but they also integrate these various considerations into a unified representation of modality. (shrink)

I examine the familiar quadruple of categorical statements “Every F is/is not G.”, “Some F is/is not G.” as well as the quadruple of their modal versions “Necessarily, every F is/is not G.”, “Possibly, some F is/is not G.”. I focus on their existential import and its impact on the resulting Squares of Opposition. Though my construal of existential import follows modern approach, I add some extra details which are enabled by framing my definition of existential import within expressively rich (...) higher-order partial type logic. As regards the modal categorical statements, I find that so-called void properties bring existential import to them, so they are the only properties which invalidate subalternation, and thus also contrariety and subcontrariety, in the corresponding Square of Opposition. (shrink)

Dispositionalism about modality is the view that metaphysical modality is a matter of the dispositions possessed by actual objects. In a recent paper, David Yates has raised an important worry about the formal adequacy of dispositionalism. This paper responds to Yates’s worry by developing a reply that Yates discusses briefly but dismisses as ad hoc: an appeal to a ’plenitude of powers’ including such powers as the necessarily always manifested power for 2+2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} (...) \begin{document}$$2+2$$\end{document} to be 4. I argue that the reply is not ad hoc at all, by defending the metaphysics of dispositions that should underly it. I then argue, first, that a proper understanding of dispositions’ degrees provides us with an argument for such necessarily always manifested dispositions; second, that all the natural attempts to block that argument can be resisted without being ad hoc; and third, that pragmatic considerations explain our intuitive resistance to the ascription of necessarily always manifested dispositions. Dispositionalism can be formally adequate after all. (shrink)

Vetter's Potentiality is an exposition and development of a new account of possibility and necessity, given in terms of potentialities. In this critical notice, I give an outline of some of the key claims of the book. I then raise some issues for the extent to which Vetter's view can accommodate genuine de re modalities, especially those of possible existence and non-existence.

Traditional conventionalism about modality claims that a proposition is necessarily true iff it is true by convention. In the wake of the widespread repudiation of truth-byconvention, traditional conventionalism has fallen out of favour. However, a family of theories of modality have arisen that, whilst abandoning truth-by-convention, retain the spirit of traditional conventionalism. These ‘neo-conventionalist’ theories surpass their forebears and don’t fall victim to the criticisms inherited through truth-by-convention. However, not all criticisms levelled at traditional conventionalism target truth-by-convention. Any conventional theory (...) of modality must face the contingency problem. This claims that the contingency of our linguistic conventions jeopardises the necessity of the necessities they determine. I present the contingency problem as relevant to both the traditional conventionalist and the neo-conventionalist. I examine a response from Einheuser that builds upon a response from Wright. I show that the Einheuser response does more to accommodate the conventionalist’s modal beliefs, but that it does not fully satisfy some further conditions that ought to be laid upon such a response. I then suggest how the response can be revised so as to satisfy these conditions. The resulting model of conventionalism is compatible with the validity of S4, and suitably in the spirit of conventionalism. (shrink)

In this study, we examine modern reading of the Square of Opposition by means of Tichý's Transparent intensional logic. Explicit use of possible world semantics helps us to sharply discriminate between standard and modal readings of categorial statements. We thus get two basic versions of the Square, whereas the Modal Square has not been fully introduced in the contemporary debate yet. Some properties ascribed by mediaeval logicians to the Square require a shift from its Standard to Modal version. Not inevitably, (...) because for each of the two squares there exists its mate which can be easily confused with it. We thus investigate four distinct squares. The discrimination between the initial and modified versions of the Standard and Modal Square leads to better knowledge of the Square as well as a solution of various puzzles often mentioned in recent literature. (shrink)

On one influential view, metaphysical fundamentality can be understood in terms of joint‐carving. Ted Sider has recently argued that (i) some first order quantifier is joint‐carving, and (ii) modal notions are not joint‐carving. After vindicating the theoretical indispensability of quantification against recent criticism, I will defend a logical result due to Arnold Koslow which implies that (i) and (ii) are incompatible. I will therefore consider an alternative understanding of Sider's metaphysics to the effect that (i) some first order quantifier is (...) joint‐carving, and (iii) intensional notions are not joint‐carving. Another result due to Koslow entails that (i) and (iii) are also incompatible. I will argue that this second result is inconclusive. Nevertheless, (iii) is incompatible with another tenet of Sider's metaphysics, namely that (iv) ‘being joint‐carving’ is itself joint‐carving. In order to resolve the inconsistency, I will tentatively argue that condition (iv) should be renounced. (shrink)

This brief note critically assesses the central arguments in Morato’s recent contribution to the growing literature on Blackburn’s dilemma about necessity. In particular, I demonstrate that neither of Morato’s two novel reconstructions of the dilemma’s contingency horn succeed, since both turn on false premises; and, Morato fails to adequately motivate his own response to these reconstructions. The upshot is that Morato has set himself a pair of flawed problems, then offered a flawed solution.

In his late fragment, ‘Sources of Knowledge of Mathematics and Natural Sciences’ Frege laments the tendency to confuse functions with objects and says, ‘It is here that the tendency of language by its use of the definite article to stamp as an object what is a function and hence a non-object, proves itself to be the source of inaccurate and misleading expressions and also of errors of thought. Probably most of the impurities that contaminate the logical source of knowledge have (...) their origins in this.’ This paper applies Frege’s logical insights to a series of influential modal arguments for the existence of souls or minds, in order to demonstrate that they hinge on the error of treating functions as objects. Related arguments have also resulted in the claim that identity statements are necessary, and that apparent identities ‘really’ involve relations of constitution. Here it is argued that once we recognise that all these arguments involve the assimilation of objects and concepts (which Frege identifies with functions) they can be seen to be defective. (shrink)

Proceedings of the 2016 "one word" colloquium of the The Philosophical Society of Finland. The word was "Possibility".

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.

Could There Have Been Nothing? Against Metaphysical Nihilism, by CogginsGeraldine. Basingstoke : Palgrave Macmillan, 2010. Pp. xii + 171.

Over the last half century, possible worlds have bled into almost every area of philosophy. In the metaphysics of modality, for example, philosophers have used possible worlds almost exclusively to illuminate discourse about metaphysical necessity and possibility. But recently, some have grown dissatisfied with possible worlds. Why are horses necessarily mammals? Because the property of being a horse bears a special relationship to the property of being a mammal, they say. Not because every horse is a mammal in every possible (...) world. Some have recently begun to use properties to develop rivals to possible worlds semantics which may someday compare in formal power and capture the different systems of modal logic. In this paper, I do two things. I first offer a quick primer on possible worlds semantics. Then I discuss three rivals and the work they have left to do. (shrink)

This special issue of the Canadian Journal of Philosophy is dedicated to Timothy Williamson's work on modality. It consists of a new paper by Williamson followed by papers on Williamson's work on modality, with each followed by a reply by Williamson. -/- Contributors: Andrew Bacon, Kit Fine, Peter Fritz, Jeremy Goodman, John Hawthorne, Øystein Linnebo, Ted Sider, Robert Stalnaker, Meghan Sullivan, Gabriel Uzquiano, Barbara Vetter, Timothy Williamson, Juhani Yli-Vakkuri.

This paper discusses proof-theoretic semantics, the project of specifying the meanings of the logical constants in terms of rules of inference governing them. I concentrate on Michael Dummett’s and Dag Prawitz’ philosophical motivations and give precise characterisations of the crucial notions of harmony and stability, placed in the context of proving normalisation results in systems of natural deduction. I point out a problem for defining the meaning of negation in this framework and prospects for an account of the meanings of (...) modal operators in terms of rules of inference. (shrink)

The review is a summary of the main thrust of Leftow's rich and very interesting theistic account of alethic possibility and necessity.