This paper is devoted to present Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method for multi-attribute group decision making under rough neutrosophic environment. The concept of rough neutrosophic set is a powerful mathematical tool to deal with uncertainty, indeterminacy and inconsistency. In this paper, a new approach for multi-attribute group decision making problems is proposed by extending the TOPSIS method under rough neutrosophic environment. Rough neutrosophic set is characterized by the upper and lower approximation operators and the (...) pair of neutrosophic sets that are characterized by truth-membership degree, indeterminacy membership degree, and falsity membership degree. In the decision situation, ratings of alternatives with respect to each attribute are characterized by rough neutrosophic sets that reflect the decision makers’ opinion. Rough neutrosophic weighted averaging operator has been used to aggregate the individual decision maker’s opinion into group opinion for rating the importance of attributes and alternatives. Finally, a numerical example has been provided to demonstrate the applicability and effectiveness of the proposed approach. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:LITERAL AND METAPHORICAL USES OF DISCOURSE IN THE REPRESENTATION OF GOD IN HIS SEMINAL work on the theory of signs, Charles Morris affirms that human beings are " the dominant sign-using animals" and that" the human mind is inseparable from the functioning of signs-if indeed mentality is not to be identified with such functioning." 1 By means of acculturation we learn to use and interpret signs, both linguistic and (...) non-linguistic; and by virtue of these capacities we can appropriately designate the human animal as homo symbolicus, homo loquens, and homo sapiens. Indeed, all forms of human culture presuppose the ability to use and interpret signs, including that form of human culture which leads us to speak of ourselves as homo religious. Over the years I have come to understand and speak of religion as a community with its cultus. There is the community, be it triba1, national, or universal with its polity or structure and ongoing history; and there is the cultus with its organic system of linguistic and nonlinguistic signs, encompassing ·such elements as stories, creeds, scriptures, doctrines, theologies, confessions, prayers, chants, songs, rites, rituals, sacraments, artifacts, etc. Like any other cultural system, scheme or network of signs one can characterize a religious cultus as an inter -subjective set of signs whose usage is determined by the implicit or explicit rules that govern the relations of signs to each other; the relations of the signs to the objects which the signs designate or denote, or stand for in some way; and the relations of signs to the users or interpreters of these signs and to those who are affected by these signs in some way. 1 Charles W. Morris, FoundatioJi of the Theory of Signs, in International Encyclopedia of Unified Science, Vol. I, No. 2 (Chicago: University of Chicago Press, 1939), p. L 6~7 628 WILLIAM L. POWER: Given this understanding of community and cultus, one can describe a religion as an organized group of socially interdependent human beings which uses or employs ·a system of linguistic and nonlinguistic signs to represent reality in its various modalities and mixtures of good and evil and to affect human ways of life on the basis of that representation. Altering the terminology somewhat, one could say that a religious community uses its cultus to proclaim, enact, and display a comprehensive worldview.and to form and tr:msform the ethospathos of human beings in their solidarity and solitude. Expressed semiotically, there is the system of signs of a particular community, the intended signification of these signs, and the significance of these signs for those who use and are affected by them. What distinguishes a religion from other forms of human culture is that a rel·igious cultuml sy•stem or a religious community with its cultus is primarily concerned with ultimate or supreme reality or with that which is divine, holy, or sacred and that reality's bearing on and relevance for human life and well-being. In short, a religion is a cultural system which functions to map the whole of re.ality and to acculturate in desirable ways or to civilize. If a religion is a cultural system, then one can identify three distinct yet inseparably related dimensions of every religion. There is 1) the cultural dimension consisting of the interrelruted signs, symbols and expressions of a cultus; 2) the reality and value dimension consisting of the ontological and axiological purport of the cultus; and 3) the experiential dimension consisting of the existential import of the cultus. It is this thioo dimension which has led many in the past and in the present to speak of religion as piety, consciousness of things divine, ultimate concern, religiousness, etc. In the tradition of Peircian semiotics, one can speak of these three dimensions as the syntactic, semantic, and praigmatic dimensions of a religion; and they can be analyzed and studied with the aid of syntactics or syntax, semantics, and pr:agmatics, which as a unity LITERAL AND METAPHORICAL USES OF DISCOURSE 629 constitute the discipline of semiotics. As Peirce recognized, modem semiotics is continuous with the Medieval trivium of grammar, logic, and rhetoric-the semiotics of almost a millennium a;go... (shrink)

Possible worlds, concrete or abstract as you like, are irrelevant to the truthmakers for modality—or so I shall argue in this paper. First, I present the neo-Humean picture of modality, and explain why those who accept it deny a common sense view of modality. Second, I present what I take to be the most pressing objection to the neo-Humean account, one that, I argue, applies equally well to any theory that grounds modality in possible worlds. Third, I present an alternative, (...) properties-based theory of modality and explore several specific ways to flesh the general proposal out, including my favored version, the powers theory. And, fourth, I offer a powers semantics for counterfactuals that each version of the properties-based theory of modality can accept, mutatis mutandis. Together with a definition of possibility and necessity in terms of counterfactuals, the powers semantics of counterfactuals generates a semantics for modality that appeals to causal powers and not possible worlds. (shrink)

Any successful account of the metaphysics of mechanistic causation must satisfy at least five key desiderata. In this article, I lay out these five desiderata and explain why existing accounts of the metaphysics of mechanistic causation fail to satisfy them. I then present an alternative account that does satisfy the five desiderata. According to this alternative account, we must resort to a type of ontological entity that is new to metaphysics, but not to science: constraints. In this article, I explain (...) how a constraints-based metaphysics fits best with the emerging consensus on the nature of mechanistic explanation. 1Introduction2Renormalizability2.1The first two desiderata: Intrinsicness and productivity2.2The third desideratum: Scientific validity or non-mysteriousness2.3The fourth desideratum: Directionality2.4The fifth desideratum: Perspectival nature of mechanisms3Constraints and Causation3.1Multi-perspectival realism and causal structure3.2Causal structure as laws3.3Causal structures in analytical mechanics: Constraints3.4A metaphysics inspired by analytical mechanics: Constraints as ontologically primitive modal structures4Constraints and Mechanistic Causal Powers 4.1Inter- versus intra-perspectival categories4.2Mechanistic causal powers are grounded by constraints4.3Intrinsicness and constraints4.4Constraints and productiveness4.5Constraints and directionality5Conclusion. (shrink)

Many authors have noted that there are types of English modal sentences cannot be formalized in the language of basic first-order modal logic. Some widely discussed examples include “There could have been things other than there actually are” and “Everyone who is actually rich could have been poor.” In response to this lack of expressive power, many authors have discussed extensions of first-order modal logic with two-dimensional operators. But claims about the relative expressive power of (...) these extensions are often justified only by example rather than by rigorous proof. In this paper, we provide proofs of many of these claims and present a more complete picture of the expressive landscape for such languages. (shrink)

A complex theory concerning powers, natures, and causal necessity has emerged from the writings of P. H. Hare, E. H. Madden, and R. Harré. In the course of rebutting objections that other critics have raised to the power account of causation, I correct three of its genuine difficulties: its attempt to analyze power attributions in terms of conditional statements; its characterization of the relation between something's powers and its nature; and its doctrines concerning conceptual necessity. The resulting interpretation (...) of causal modalities is then subsumed under a more general power account of modality, related at a number of points to considerations concerning powers, and further illustrating their philosophical importance. (shrink)

In this article I critically assess Deleuze’s interpretation of Spinoza’s metaphysics of modes. I argue that the conception of modal essence that Deleuze attributes to Spinoza is untenable in terms of Spinoza’s metaphysics. I further show that the idea that modal essences are eternally static degrees of power is incompatible with Spinoza’s ethics, wherein modes strive to increase their power by means of positive interactions with others. I suggest that Deleuze’s interpretation of this crucial aspect of (...) Spinozism runs the risk of reinstating Platonic idealist and moralistic themes, of the kind that both Spinoza and Deleuze are committed to overcoming. (shrink)

In this paper I examine Grace A. de Laguna’s theory of universals in its historical context and in relation to contemporary debates in analytic metaphysics. I explain the central features of her theory, arguing that her theory should be classified as a form of immanent realism and as a powers ontology. I then show in what ways her theory affords a theory of modality in terms of potentialities and discuss some of its consequences along the way.

We illustrate, with three examples, the interaction between boolean and modal connectives by looking at the role of truth-functional reasoning in the provision of completeness proofs for normal modal logics. The first example (§ 1) is of a logic (more accurately: range of logics) which is incomplete in the sense of being determined by no class of Kripke frames, where the incompleteness is entirely due to the lack of boolean negation amongst the underlying non-modal connectives. The second (...) example (§ 2) focusses on the breakdown, in the absence of boolean disjunction, of the usual canonical model argument for the logic of dense Kripke frames, though a proof of incompleteness with respect to the Kripke semantics is not offered. An alternative semantic account is developed, in terms of which a completeness proof can be given, and this is used (§ 3) in the discussion of the third example, a bimodal logic which is, as with the first example, provably incomplete in terms of the Kripke semantics, the incompleteness being due to the lack of disjunction (as a primitive or defined boolean connective). (shrink)

In _Modal Logic for Open Minds,_ Johan van Benthem provides an up-to-date introduction to the field of modal logic, outlining its major ideas and exploring the numerous ways in which various academic fields have adopted it. Van Benthem begins with the basic theories of modal logic, semantics, bisimulation, and axiomatics, and also covers more advanced topics, such as expressive power and computational complexity. The book then moves to a wide range of applications, including new developments in information (...) flow, intelligent agency, and games. Taken together, the chapters show modal logic at the crossroads of philosophy, mathematics, linguistics, computer science, and economics. Most of the chapters are followed by exercises, making this volume ideal for undergraduate and graduate students in philosophy, computer science, symbolic systems, cognitive science, and linguistics. (shrink)

It is shown that the expressive power of second-order propositional modal logic whose modalities are S4.2 or weaker is the same as that of second-order predicate logic.

Individual objects have potentials: paper has the potential to burn, an acorn has the potential to turn into a tree, some people have the potential to run a mile in less than four minutes. Barbara Vetter provides a systematic investigation into the metaphysics of such potentials, and an account of metaphysical modality based on them. -/- In contemporary philosophy, potentials have been recognized mostly in the form of so-called dispositions: solubility, fragility, and so on. Vetter takes dispositions as her starting (...) point, but argues for and develops a more comprehensive conception of potentiality. She shows how, with this more comprehensive conception, an account of metaphysical modality can be given that meets three crucial requirements: Extensional correctness: providing the right truth-values for statements of possibility and necessity; formal adequacy: providing the right logic for metaphysical modality; and semantic utility: providing a semantics that links ordinary modal language to the metaphysics of modality. -/- The resulting view of modality is a version of dispositionalism about modality: it takes modality to be a matter of the dispositions of individual objects. This approach has a long philosophical tradition going back to Aristotle, but has been largely neglected in contemporary philosophy. In recent years, it has become a live option again due to the rise of anti-Humean, powers-based metaphysics. The aim of Potentiality is to develop the dispositionalist view in a way that takes account of contemporary developments in metaphysics, logic, and semantics. (shrink)

Actualists of a certain stripe—dispositionalists—hold that metaphysical modality is grounded in the powers of actual things. Roughly: p is possible iff something has, or some things have, the power to bring it about that p. Extant critiques of dispositionalism focus on its material adequacy, and question whether there are enough powers to account for all the possibilities we intuitively want to countenance. For instance, it seems possible that none of the actual contingent particulars ever existed, but it is impossible (...) to explain this by appealing to the powers of some actual thing or things to bring it about. I argue instead that dispositionalism, in the simple form championed by its proponents, is formally inadequate. Dispositionalists interpret the modal operators as simple existential claims about powers, but if we interpret the operators that way, the resulting system of modal logic is too weak to capture metaphysical modality. I argue that we can modify the standard dispositionalist interpretations of the operators to secure formal adequacy, but at the cost of accepting that not all modality is grounded in powers. This, I shall suggest, is not a bad thing—the resulting theory still has powers at its core and has certain attractive features, in addition to formal adequacy, that the standard theory lacks. (shrink)

Power is clearly a crucial concept for feminist theory. Insofar as feminists are interested in analyzing power, it is because they have an interest in understanding, critiquing, and ultimately challenging the multiple array of unjust power relations affecting women in contemporary Western societies, including sexism, racism, heterosexism, and class oppression. In "The Power of Feminist Theory," Amy Allen diagnoses the inadequacies of previous feminist conceptions of power, and draws on the work of a diverse group (...) of theorists of power, including Michel Foucault, Judith Butler, and Hannah Arendt, in order to construct a new feminist conception of power. The conception of power developed in this book enables readers to theorize domination, resistance, and solidarity, and, perhaps more importantly, to do so in a way that illuminates the interrelatedness of these three modalities of power. (shrink)

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)

We develop a method for showing that various modal logics that are valid in their countably generated canonical Kripke frames must also be valid in their uncountably generated ones. This is applied to many systems, including the logics of finite width, and a broader class of multimodal logics of ‘finite achronal width’ that are introduced here.

In _Modal Logic for Open Minds,_ Johan van Benthem provides an up-to-date introduction to the field of modal logic, outlining its major ideas and exploring the numerous ways in which various academic fields have adopted it. Van Benthem begins with the basic theories of modal logic, semantics, bisimulation, and axiomatics, and also covers more advanced topics, such as expressive power and computational complexity. The book then moves to a wide range of applications, including new developments in information (...) flow, intelligent agency, and games. Taken together, the chapters show modal logic at the crossroads of philosophy, mathematics, linguistics, computer science, and economics. Most of the chapters are followed by exercises, making this volume ideal for undergraduate and graduate students in philosophy, computer science, symbolic systems, cognitive science, and linguistics. (shrink)

Dispositionalism is the theory of modality that grounds all modal truths in powers: all metaphysically possible and necessary truths are to be explained by pointing to some actual power, or absence thereof. One of the main reasons to endorse dispositionalism is that it promises to deliver an especially desirable epistemology of modality. However, so far this issue has not be fully investigated with the care it is due. The aim of this paper is to fill this gap. We (...) will cast some doubts on whether the dispositionalist really is in a better position to explain our modal knowledge. In fact, we argue that there is a tension between some core tenets of a powers metaphysics and the very features that make dispositionalism the ideal backdrop for a desirable epistemology of modality. We conclude that this leaves dispositionalists who want to deliver the promised epistemology with a hard, currently unfulfilled, task. (shrink)

Our concern here is with the extent to which the expressive equivalence of Wehmeier’s Subjunctive Modal Language and the Actuality Modal Language is sensitive to the choice of background modal logic. In particular we will show that, when we are enriching quantified modal logics weaker than S5, AML is strictly expressively stronger than SML, this result following from general considerations regarding the relationship between operators and predicate markers. This would seem to complicate arguments given in favour (...) of SML which rely upon its being expressively equivalent to AML. (shrink)

Neil E. Williams develops a systematic metaphysics centred on the idea of powers, as a rival to neo-Humeanism, the dominant systematic metaphysics in philosophy today. Williams takes powers to be inherently causal properties and uses them as the foundation of his explanations of causation, persistence, laws, and modality.

We investigate the modal logic of stepwise removal of objects, both for its intrinsic interest as a logic of quantification without replacement, and as a pilot study to better understand the complexity jumps between dynamic epistemic logics of model transformations and logics of freely chosen graph changes that get registered in a growing memory. After introducing this logic (MLSR) and its corresponding removal modality, we analyze its expressive power and prove a bisimulation characterization theorem. We then provide a (...) complete Hillbert-style axiomatization for the logic of stepwise removal in a hybrid language enriched with nominals and public announcement operators. Next, we show that model-checking for MLSR is PSPACE-complete, while its satisfiability problem is undecidable. Lastly, we consider an issue of fine-structure: the expressive power gained by adding the stepwise removal modality to fragments of first-order logic. (shrink)

Theistic modal realism argues for an extension of Lewis's modal realism capable of accommodating a theistic God. By affording elegant solutions to many atheistic challenges, the view is of great theoretical utility for the theist. However, it has been objected that within a Lewisian framework God cannot be causally efficacious on pain of collapsing intuitively distinct modal notions. In this article I explain why these worries are ill-founded and show how God's existence and causal power over (...) the pluriverse can be consistently understood. If successful, the proposal offers a congenial theistic way to adopt modal realism and address the atheological problems. (shrink)

Dispositionalism is the theory of modality according to which all (metaphysical and natural) modal truths are made true by some actual irreducibly dispositional property. The relationship between Dispositionalism and time is yet to be satisfactorily explored. In this paper we contribute to this task by examining how Dispositionalism deals with ‘dated truths’: propositions involving a specific time, e.g. “It might rain at 12.30”. We examine two possible accounts: the first, 'Dated Manifestations Strategy', is the idea that powers are very (...) fine-grained, and tend towards temporally very specific manifestations. We argue that such strategy should not be adopted, for it leads to unnecessary violations of ontological parsimony; it is unable to accommodate an ontology of platonic universals; and it is incapable of offering a principled explanation of the forward-looking nature of powers. We offer an alternative account, the "Duration Strategy", which relies on an independently determined arrow of time and the existence of some “duration facts” that specify how long a power takes to bring about its manifestation. We argue that the Duration Strategy is to be preferred. We then flesh out the account by exploring the connection between powers, duration facts, and processes. (shrink)

We introduce the subject of modal model theory, where one studies a mathematical structure within a class of similar structures under an extension concept that gives rise to mathematically natural notions of possibility and necessity. A statement φ is possible in a structure (written φ) if φ is true in some extension of that structure, and φ is necessary (written φ) if it is true in all extensions of the structure. A principal case for us will be the class (...) Mod(T) of all models of a given theory T—all graphs, all groups, all fields, or what have you—considered under the substructure relation. In this article, we aim to develop the resulting modal model theory. The class of all graphs is a particularly insightful case illustrating the remarkable power of the modal vocabulary, for the modal language of graph theory can express connectedness, k-colorability, finiteness, countability, size continuum, size ℵ1, ℵ2, ℵω, ℶω, first ℶ-fixed point, first ℶ-hyper-fixed point, and much more. A graph obeys the maximality principle φ(a)→φ(a) with parameters if and only if it satisfies the theory of the countable random graph, and it satisfies the maximality principle for sentences if and only if it is universal for finite graphs. (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)

The modal object calculus is the system of logic which houses the (proper) axiomatic theory of abstract objects. The calculus has some rather interesting features in and of itself, independent of the proper theory. The most sophisticated, type-theoretic incarnation of the calculus can be used to analyze the intensional contexts of natural language and so constitutes an intensional logic. However, the simpler second-order version of the calculus couches a theory of fine-grained properties, relations and propositions and serves as a (...) framework for defining situations, possible worlds, stories, and fictional characters, among other things. In the present paper, we focus on the second-order calculus. The second-order modal object calculus is so-called to distinguish it from the second-order modal predicate calculus. Though the differences are slight, the extra expressive power of the object calculus significantly enhances its ability to resolve logical and philosophical concepts and problems. (shrink)

In this paper, I distinguish between two varieties of actualism—hardcore actualism and softcore actualism—and I critically discuss Ross Cameron’s recent arguments for preferring a softcore actualist account of the truthmakers for modal truths over hardcore actualist ones. In the process, I offer some arguments for preferring the hardcore actualist account of modal truthmakers over the softcore actualist one.

I propose that we approach the epistemology of modality by putting modal metaphysics first and, specifically, by investigating the metaphysics of essence. Following a prominent Neo-Aristotelian view, I hold that metaphysical necessity depends on the nature of things, namely their essences. I further clarify that essences are core properties having distinctive superexplanatory powers. In the case of natural kinds, which is my focus in the paper, superexplanatoriness is due to the fact that the essence of a kind is what (...) causes all the many properties and behaviors that are typically shared by all the instances of the kind. Accordingly, we know what is necessarily true of kinds by knowing what is essential to them in the sense of actually playing such causal-explanatory roles. Modal reasoning aimed at discovering metaphysical necessity thus proceeds via essentialist deduction: we move from essentialist truths to reach necessary truths. (shrink)

This chapter explores a potential analogy between mereological principles and laws of nature. Against a backdrop of what Marmodoro has termed ‘power structuralism’ (and a rejection of a Humean worldview), the connection between parthood and modality may be richer than has hitherto been considered. Mereological principles delineate possibilities for parts and wholes, and putting powers at the centre of a discussion about parthood can furnish a novel conception of mereological laws, much as dispositionalism has done so for natural laws; (...) namely, these principles express connections between fundamental dispositional properties. By extending dispositionalism to comprehend mereology in this way, we can help fulfil its promise to provide a foundational, naturalistic metaphysics, as foundational mereological debates then begin to mirror those relating to dispositionalist views of laws of nature: we may treat natural and mereological laws in tandem, as holding either necessarily or contingently, with associated strategies for dealing with supposed counterexamples to one’s preferred set of mereological principles. We can thus bring new life to the debate over whether questions of composition admit of contingent or only necessary answers. (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)

A powerful challenge to some highly influential theories, this book offers a thorough critical exposition of modal realism, the philosophical doctrine that many possible worlds exist of which our own universe is just one. Chihara challenges this claim and offers a new argument for modality without worlds.

Dispositionality is a modal notion of a certain sort. When an object is said to have a disposition, we typically understand this to mean that under certain circumstances, the object would behave in a certain way. For instance, a fragile object is disposed to break when dropped onto a concrete surface. It need not actually break - its being fragile has implications that, so to speak, point beyond the actual world. According to dispositionalism, all modal features of the (...) world may be accounted for in terms of its dispositional features. My aim in this paper is to assess the prospects for dispositionalism by examining the most promising theories. Sections 1 and 2 clarify the assumptions and desiderata of a successful dispositionalist theory of modality. Section 3 introduces the principles governing the dispositionalist theories that apparently meet the desiderata. Sections 4 through 6 show that dispositionalism nonetheless faces three problems: while dispositions help account for modal features of the world that are local, diachronic, or gradable, they cannot account for certain modal features of the world that are global, synchronic, or absolute. I end by discussing the costs of preserving dispositionalism. (shrink)

We investigate an enrichment of the propositional modal language L with a "universal" modality ■ having semantics x ⊧ ■φ iff ∀y(y ⊧ φ), and a countable set of "names" - a special kind of propositional variables ranging over singleton sets of worlds. The obtained language ℒ $_{c}$ proves to have a great expressive power. It is equivalent with respect to modal definability to another enrichment ℒ(⍯) of ℒ, where ⍯ is an additional modality with the semantics (...) x ⊧ ⍯φ iff Vy(y ≠ x → y ⊧ φ). Model-theoretic characterizations of modal definability in these languages are obtained. Further we consider deductive systems in ℒ $_{c}$ . Strong completeness of the normal ℒ $_{c}$ logics is proved with respect to models in which all worlds are named. Every ℒ $_{c}$ -logic axiomatized by formulae containing only names (but not propositional variables) is proved to be strongly frame-complete. Problems concerning transfer of properties ([in]completeness, filtration, finite model property etc.) from ℒ to ℒ $_{c}$ are discussed. Finally, further perspectives for names in multimodal environment are briefly sketched. (shrink)

"Powers and Capacities in Philosophy" is designed to stake out an emerging, discipline-spanning neo-Aristotelian framework grounded in realism about causal powers. The volume brings together for the first time original essays by leading philosophers working on powers in relation to metaphysics, philosophy of natural and social science, philosophy of mind and action, epistemology, ethics and social and political philosophy. In each area, the concern is to show how a commitment to real causal powers affects discussion at the level in question. (...) In metaphysics, for example, realism about powers is now recognized as providing an alternative to orthodox accounts of causation, modality, properties and laws. Dispositional realist philosophers of science, meanwhile, argue that a powers ontology allows for a proper account of the nature of scientific explanation. In the philosophy of mind there is the suggestion that agency is best understood in terms of the distinctive powers of human beings. Those who take virtue theoretic approaches in epistemology and ethics have long been interested in the powers that allow for knowledge and/or moral excellence. In social and political philosophy, finally, powers theorists are interested in the powers of sociological phenomena such as collectivities, institutions, roles and/or social relations, but also in the conditions of possibility for the cultivation of the powers of individuals. The book will be of interest to philosophers working in any of these areas, as well as to historians of philosophy, political theorists and critical realists. (shrink)

There has been much discussion of powers or real dispositions in the past decade, but there remains an issue that has been inadequately treated. This concerns the precise modal value that comes with dispositionality. We contend in this paper that dispositionality involves a non-alethic, sui generis, irreducible modality. Dispositions only tend towards their manifestations; they do not necessitate them. Tendency is, of course, a dispositional term itself, so this last statement offers little by way of illumination. But given our (...) thesis on the irreducible nature of dispositionality, we maintain that it cannot be explicated correctly in non-dispositional terms. Nevertheless, we all have experience of dispositionality at work, through the exercise or our own powers and the action of other powers upon us. The notion of dispositionality that we acquire is one that involves a modality stronger than pure contingency but weaker than necessity. The recognition of this distinct modal value for dispositionality is one of the biggest oversights in the growing literature in the area. Yet it is there for all to see in even the most mundane example. (shrink)

This dissertation is about flexibility as a dimension of reality, an objective—independent of mind and language—phenomenon typically referred to as ‘metaphysical modality’. It develops a novel modal account of why reality could be different: that is, why claims like “Possibly, there are talking donkeys,” or “Humphrey could have won the election” are true or false. I contend that primitive dispositional properties called ‘powers’ explain such claims, and do so better than possible-world accounts of modality. The problem with possible-world accounts (...) is that they fail to capture what we mean by modal terms like ‘possibly’, ‘can’, or ‘necessarily’. The phenomenon they capture with possible worlds cannot adequately explain, for instance, that Humphrey regrets not winning the election because: he could have made a difference. Humphrey is told that he could have won the election because some entity represents him as such. But what does some entity’s representing Humphrey have to do with whether Humphrey could have won the election? Simply calling that entity a ‘possible world’ is no help. Powers do better in this regard, preserving a common-sense notion of modality where, because of what a power can do it acts as a cross-roads in history, marking places where reality could have unfolded differently. As such, powers are more clearly modally significant than possible worlds. The conclusion shows how to use powers to underwrite possible-world semantics without possible worlds. (shrink)

The British Journal for the Philosophy of Science, axy042.

When embedding data are used to argue against semantic theory A and in favor of semantic theory B, it is important to ask whether A could make sense of those data. It is possible to ask that question on a case-by-case basis. But suppose we could show that A can make sense of all the embedding data which B can possibly make sense of. This would, on the one hand, undermine arguments in favor of B over A on the basis (...) of embedding data. And, provided that the converse does not hold—that is, that A can make sense of strictly more embedding data than B can—it would also show that there is a precise sense in which B is more constrained than A, yielding a pro tanto simplicity-based consideration in favor of B. In this paper I develop tools which allow us to make comparisons of this kind, which I call comparisons of potential expressive power. I motivate the development of these tools by way of exploration of the recent debate about epistemic modals. Prominent theories which have been developed in response to embedding data turn out to be strictly less expressive than the standard relational theory, a fact which necessitates a reorientation in how to think about the choice between these theories. (shrink)

Is it metaphysically possible for a world to contain power properties but no nonpower properties? Recently, much progress has been made by powers theorists to defend the coherence of such a possibility. But unfortunately, it remains unclear how the powers in a power world are individuated. The problem is that the most obvious principle of individuation for properties in a power world is one that is circular. In this paper, it is argued that this circularity is generated (...) by a modal assumption, which is that different families of powers exist in different possible worlds. By rejecting this assumption, a noncircular principle of individuation for power properties can be formulated. Moreover, this solution is not ad hoc because there are independent reasons for rejecting the aforementioned modal assumption. (shrink)

We consider some modal languages with a modal operator $D$ whose semantics is based on the relation of inequality. Basic logical properties such as definability, expressive power and completeness are studied. Also, some connections with a number of other recent proposals to extend the standard modal language are pointed at.

Thomas Hobbes often includes powers and abilities in his descriptions of the world. Meanwhile, Hobbes’s philosophical picture of the world appears quite reductive, and he seems sometimes to say that nothing exists but bodies in motion. In more extreme versions of such a picture, there would be no room for powers. Hobbes is not an eliminativist about powers, but his view does tend toward ontological minimalism. It would be good to have an account of what Hobbes thinks powers are, and (...) how they fit into his understanding of the world. In this chapter, I investigate Hobbes’s account of the metaphysics of powers and abilities. Section 1 considers three important aspects of Hobbes’s account of powers: the connection between powers and causes; the modal aspects of powers; and the connection between powers and motions. Sections 2 and 3 then consider interpretive arguments about whether Hobbes identifies powers with underlying corporeal features. (shrink)