Upward monotonic semantics for necessity modals give rise to Ross’s Puzzle: they predict that □φ entails □(φ ∨ ψ), but common intuitions about arguments of this form suggest they are invalid. It is widely assumed that the intuitive judgments involved in Ross’s Puzzle can be explained in terms of the licensing of ‘Diversity’ inferences: from □(φ ∨ ψ), interpreters infer that the truth of each disjunct (φ, ψ) is compatible with the relevant set of worlds. I introduce two (...) pieces of data that this analysis fails to explain. Analyzing this data, I argue, suggests that necessity modals with embedded disjunctions license ‘Independence’ inferences: from the truth of □(φ ∨ ψ), interpreters infer that φ-without-ψ and ψ-without-φ are each compatible with the relevant set of worlds. I outline a bilateral inquisitive semantics for necessity modals that predicts the validity of the Independence inferences. I then argue that the resulting theory should be understood as one on which disjunctions denote pluralities of propositions, and necessity modals behave like collective predicates applied to these pluralities. (shrink)

This paper develops an account of the meaning of `ought', and the distinction between weak necessity modals (`ought', `should') and strong necessity modals (`must', `have to'). I argue that there is nothing specially ``strong'' about strong necessity modals per se: uses of `Must p' predicate the (deontic/epistemic/etc.) necessity of the prejacent p of the actual world (evaluation world). The apparent ``weakness'' of weak necessity modals derives from their bracketing whether the (...) class='Hi'>necessity of the prejacent is verified in the actual world. `Ought p' can be accepted without needing to settle that the relevant considerations (norms, expectations, etc.) that actually apply verify the necessity of p. I call the basic account a modal-past approach to the weak/strong necessity modal distinction (for reasons that become evident). Several ways of implementing the approach in the formal semantics/pragmatics are critically examined. The account systematizes a wide range of linguistic phenomena: it generalizes across flavors of modality; it elucidates a special role that weak necessity modals play in discourse and planning; it captures contrasting logical, expressive, and illocutionary properties of weak and strong necessity modals; and it sheds light on how a notion of `ought' is often expressed in other languages. These phenomena have resisted systematic explanation. In closing I briefly consider how linguistic inquiry into differences among necessity modals may improve theorizing on broader philosophical issues. (shrink)

This paper develops an update semantics for weak necessity modals like ‘ought’ and ‘should’. I start with the basic approach to the weak/strong necessity modal distinction developed in Silk 2018: Strong necessity modals are given their familiar semantics of necessity, predicating the necessity of the prejacent of the actual world (evaluation world). The apparent “weakness” of weak necessity modals derives from their bracketing the assumption that the relevant worlds in which the (...) prejacent is necessary (deontically, epistemically, etc.) need be candidates for actuality. ‘Should φ’ can be accepted without needing to settle that the relevant considerations (norms, preferences, expectations, etc.) that actually apply, given the facts, verify the necessity of φ. I formalize these ideas within an Update with Centering framework. The meaning of ‘Should φ’ is explained, fundamentally, in terms of how its use updates attention toward possibilities in which φ is necessary. The semantics is also extended to deontic conditionals. The proposed analyses capture various contrasting logical properties and discourse properties of ‘should’ and ‘must’ — e.g., in sensitivities to standing contextual assumptions, entailingness, and force — and provide an improved treatment of largely neglected data concerning information-sensitivity. (shrink)

1 This paper has been presented at the workshop “Time and Modality: A Round Table on Tense, Mood, and Modality”, Paris, December 2005, at a CUNY linguistics colloquium in May 2006, and at the 6th Workshop on Formal Linguistics in Florian´opolis, Brazil, August 2006. We thank the audiences at those presentations, in particular Orin Percus, Tim Stowell, Marcel den Dikken, Anna Szabolcsi, Chris Warnasch, Roberta Pires de Oliveira, Renato Miguel Basso, and Ana M¨uller. We thank Noam Chomsky, Cleo Condoravdi, and (...) Irene Heim for very helpful conversations about this material. We thank Bridget Copley for sharing with us her recent manuscript “What Should Should.. (shrink)

This paper investigates when and how children figure out the force of modals: that possibility modals (e.g., _can_/_might_) express possibility, and necessity modals (e.g., _must_/_have to_) express necessity. Modals raise a classic subset problem: given that necessity entails possibility, what prevents learners from hypothesizing possibility meanings for necessity modals? Three solutions to such subset problems can be found in the literature: the first is for learners to rely on downward-entailing (DE) environments (...) (Gualmini and Schwarz in J. Semant. 26(2):185–215, 2009 ); the second is a bias for strong (here, necessity) meanings; the third is for learners to rely on pragmatic cues stemming from the conversational context (Dieuleveut et al. in Proceedings of the 2019 Amsterdam colloqnium, pp. 111–122, 2019a ; Rasin and Aravind in Nat. Lang. Semant. 29:339–375, 2020 ). This paper assesses the viability of each of these solutions by examining the modals used in speech to and by 2-year-old children, through a combination of corpus studies and experiments testing the guessability of modal force based on their context of use. Our results suggest that, given the way modals are used in speech to children, the first solution is not viable and the second is unnecessary. Instead, we argue that the conversational context in which modals occur is highly informative as to their force and sufficient, in principle, to sidestep the subset problem. Our child results further suggest an early mastery of possibility—but not necessity—modals and show no evidence for a necessity bias. (shrink)

Kolodny and MacFarlane have made a pioneering contribution to our understanding of how the interpretation of deontic modals can be sensitive to evidence and information. But integrating the discussion of information-sensitivity into the standard Kratzerian framework for modals suggests ways of capturing the relevant data without treating deontic modals as “informational modals” in their sense. I show that though one such way of capturing the data within the standard semantics fails, an alternative does not. Nevertheless I (...) argue that we have good reasons to adopt an information-sensitive semantics of the general type Kolodny and MacFarlane describe. Contrary to the standard semantics, relative deontic value between possibilities sometimes depends on which possibilities are live. I develop an ordering semantics for deontic modals that captures this point and addresses various complications introduced by integrating the discussion of information-sensitivity into the standard semantic framework. By attending to these complexities, we can also illuminate various roles that information and evidence play in logical arguments, discourse, and deliberation. (shrink)

There is an ongoing debate in the metaphysics of dispositions regarding which type of modality governs their manifestation. This paper assumes as its default position the view that dispositions manifest by conditional necessity; that is, when in appropriate circumstances dispositions manifest necessarily. From this standpoint, the paper engages critically with an existing alternative in the literature, put forward most prominently by Mumford and Anjum, and known as dispositional modality. According to this latter view, even when in appropriate manifestation conditions, (...) dispositions only merely tend towards their manifestation. By raising difficulties for this alternative, the paper offers indirect support for the conditional necessity view. (shrink)

I survey a number of views about how we can obtain knowledge of modal propositions, propositions about necessity and possibility. One major approach is that whether a proposition or state of affairs is conceivable tells us something about whether it is possible. I examine two quite different positions that fall under this rubric, those of Yablo and Chalmers. One problem for this approach is the existence of necessary a posteriori truths and I deal with some of the ways in (...) which these authors respond to the problem, including the use of two-dimensional modal semantics. Conventionalism about modality offers a complementary approach to modal epistemology, prompting us to identify our knowledge of modal truths with our mastery of linguistic or conceptual conventions. Finally, I discuss an approach to modal epistemology deriving from David Lewis's work that seeks to identify structural features of the modal space over which necessity and possibility are defined. (shrink)

First published in 1999. Routledge is an imprint of Taylor & Francis, an informa company.

In philosophical logic necessity is usually conceived as a sentential operator rather than as a predicate. An intensional sentential operator does not allow one to express quantified statements such as 'There are necessary a posteriori propositions' or 'All laws of physics are necessary' in first-order logic in a straightforward way, while they are readily formalized if necessity is formalized by a predicate. Replacing the operator conception of necessity by the predicate conception, however, causes various problems and forces (...) one to reject many philosophical accounts involving necessity that are based on the use of operator modal logic. We argue that the expressive power of the predicate account can be restored if a truth predicate is added to the language of first-order modal logic, because the predicate 'is necessary' can then be replaced by 'is necessarily true'. We prove a result showing that this substitution is technically feasible. To this end we provide partial possible-worlds semantics for the language with a predicate of necessity and perform the reduction of necessities to necessary truths. The technique applies also to many other intensional notions that have been analysed by means of modal operators. (shrink)

Readings of Hegel's account of modality tend to emphasize the “necessity of contingency” thesis. In this paper, I argue that this is not the primary aim of Hegel's “Actuality” chapter in the Science of Logic. Instead of arguing simply for the necessity of contingency, Hegel argues for the identity between contingency and necessity. I offer a reading of formal, real, and absolute modality in Hegel's Logic that shows how this identity claim is established, demonstrating that necessity (...) is not simply that which cannot be otherwise, but a process whereby something becomes what it is in becoming its other. (shrink)

The paper argues against a commitment to metaphysical necessity, semantic modalities are enough. The best approaches to elucidate the semantic modalities are (still) versions of lingustic ersatzism and fictionalism, even if only developed in parts. Within these necessary properties and the difference between natural and semantic laws can be accounted for. The proper background theory for this is an updated version of Logical Empiricism, which is congenial to recent trends in Structural Realism. The anti-metaphysical attitude of Logical Empiricism deserves (...) revitalization. Another target besides metaphysical necessity are substantial forms of iterated modalities, as used, for instance, in the philosophy of religion. (shrink)

This paper states and examines a modal argument for universal necessity, that is: for the necessary truth of every true proposition. Deep issues in the metaphysics of modality are bound up with the argument, as is revealed in the attempt to defend, or refute, it.

Interest in the metaphysics and logic of possible worlds goes back at least as far as Aristotle, but few books address the history of these important concepts. This volume offers new essays on the theories about the logical modalities held by leading philosophers from Aristotle in ancient Greece to Rudolf Carnap in the twentieth century. The story begins with an illuminating discussion of Aristotle's views on the connection between logic and metaphysics, continues through the Stoic and mediaeval traditions, and then (...) moves to the early modern period with particular attention to Locke and Leibniz. The views of Kant, Peirce, C. I. Lewis and Carnap complete the volume. Many of the essays illuminate the connection between the historical figures studied, and recent or current work in the philosophy of modality. The result is a rich and wide-ranging picture of the history of the logical modalities. (shrink)

We consider a version of so called T x W logic for historical necessity in the sense of R.H. Thomason (1984), which is somewhat special in three respects: (i) it is explicitly based on two-dimensional modal logic in the sense of Segerberg (1973); (ii) for reasons of applicability to interesting fields of philosophical logic, it conceives of time as being discrete and finite in the sense of having a beginning and an end; and (iii) it utilizes the technique of (...) systematic frame constants in order to handle the problem of irreflexivity in tense logics, well known since Gabbay (1981). Axiomatizations are given for two infinite hierarchies of two-dimensional modal tense logics, one without and one with the characteristic operators for historical necessity and possibility. Strong and weak completeness results are obtained for both hierarchies as well as a result to the effect that two approaches to their semantics are equivalent, much in the spirit of Di Maio and Zanardo (1996) and von Kutschera (1997). (shrink)

Non-modalists about essence reject the idea that metaphysical modality is prior to essence, e.g., in the sense that the latter can be reduced to or defined in terms of the former. On the contrary, according to these theorists, the explanation, if anything, proceeds in the opposite direction: metaphysical modality does not explain, but is instead explained in terms of, essence. Thus, for non-modalists like Aristotle, Kit Fine and E. J. Lowe, one of the primary theoretical roles of essence is to (...) provide an explanatory basis for metaphysical necessity and possibility. This chapter explores a range of different types of explanatory connections which raise the question of how the non-modalist’s program of explaining metaphysical modality in terms of essence is best carried out. The considerations advanced in this chapter suggest that non-modalists must proceed by way of a non-logical case-by-case engagement with specific cases, since no logical “one-size-fits- all” strategy appears to be available. (shrink)

I discuss one version of a puzzle about the identity of a statue with the lump of clay of which it is made. The case is one in which the statue and lump agree in all their non-modal features. While this is a favorable case for the claim that they are identical, we nonetheless have discrepant intuitions about their potentialities, which appear irreconcilable. Critical analyses are given of recent treatments by Allan Gibbard, Kit Fine, and Stephen Yablo. An ontologically conservative (...) solution to the puzzle is offered which has the following features: the statue and lump of clay are said to be identical, our discrepant modal intuitions about the statue and lump are validated, identity is necessary, and is a relation between objects, not concepts, Leibniz' Law is not constrained, only a standard modal logic and semantics is needed, and our modal logical intuitions are preserved. In part, this last consists in proving that standard modal logics have certain structural features. In addition, the proposed account allows that names have the same function in and out of modal contexts, namely just to refer. As well, it allows genuine de re modality, i.e. that things have genuine modal properties. How the account meets general concerns about de re modality and essentialism is discussed. The proposed method of solution is also shown to apply to a number of other modal puzzles. (shrink)

Operators can be compared in at least two respects: expressive strength and deductive strength. Inspired by Hintikka’s treatment of question embedding verbs, the variations of noncontingency operator, and also the various combinations of modal operators and Boolean connectives, we propose a logic with strong noncontingency operator as the only primitive modality. The novel operator is deductively but not expressively stronger than both noncontingency operator and essence operator, and expressively but not deductively weaker than the necessity operator. The frame-definability power (...) of this new logic is in between standard modal logic and noncontingency logic. A notion of bisimulation is proposed to characterize this logic within standard modal logic and first-order logic. Axiomatizations over various frame classes are presented, among which the minimal logic is related to the treatment of an alternative semantics of the agreement operator proposed by Lloyd Humberstone. (shrink)

In “Naming with Necessity”, it is argued that Kripke’s thesis that proper names are rigid designators is best seen as being motivated by an individual-driven picture of modality, which has two parts. First, inherent in proper-name usage is the expectation that names refer to modally robust individuals: individuals that can sustain modal predications like ‘is necessarily human’. Second, these modally robust individuals are the fundamental building blocks on the basis of which possible worlds should be conceived in a modal (...) semantics intended to mirror the conceptual apparatus behind ordinary modal talk. The individual-driven picture is distinct from two views inspired by Kripke, direct reference theory and Millianism. The former covers only the first half of the picture, while the latter explicitly gives up on that half even, opting to remain neutral about what expectation expressions impose on the nature of their referents. (shrink)

Metaphysics, as I understand it, is the attempt to construct theories which give correct accounts in general terms of pervasive structural features of reality. Though not precise and not intended as an explicit definition, this characterization is comprehensive enough to include both descriptive and revisionary varieties of metaphysical theory. The enterprise of descriptive metaphysics, Strawson tells us, consists in describing “the actual structure of our thought about the world.” Presumably a philosopher would favor this approach to metaphysics if he or (...) she believed either that the actual structure of our thought about the world provides, at least for the most part, an accurate portrait of the world’s structure or that the actual structure of our thought at any time provides privileged access, or perhaps our only access, at that time to the structure of the world. Revisionary metaphysics, by contrast, is concerned to produce a structure of thought about the world better than the one we actually have. Obviously a philosopher would adopt this approach if he or she believed that the actual structure of our thought about the world provides, in at least some important respects, an inaccurate portrait of the world’s structure and stands in need of revision in the interests of correctness. And clearly a philosopher might hold that the actual structure of our thought is quite accurate in some respects and need only be described to yield correct theory and yet is thoroughly inaccurate in others and requires substantial revision if correct theory is to be the outcome. Philosophers may, as I suppose most of them do, practice by turns descriptive and revisionary kinds of metaphysics. No global commitment to one approach or the other is required; the choice between approaches can be allowed to rest on the exigencies of local problems. (shrink)

ABSTRACTThree experiments examined how people reason about what is possible or necessary when a conditional is true. Participants were asked to indicate whether it was necessary, possible or impossible for a specific instance to conform to one of the truth-table cases, given the truth of the conditional. It was found that most participants, inconsistently, judged the pq case as necessary but the ¬pq or ¬p¬q cases as possible. Logically, these two kinds of judgments are contradictory. Moreover, a true conditional doesn’t (...) imply that a specific instance under the conditional must be pq. Therefore, people demonstrate a necessity illusion for pq cases which contradicts their commitment to the possibility of ¬pq or ¬p¬q cases. Existing accounts of conditionals are unable to explain the contradiction and the necessity illusion. We propose an inference dissociation account and explore the theoretical implications of this necessity illusion. (shrink)

This paper challenges the Kripkean interpretation of a posteriori necessities. It will be demonstrated, by an analysis of classic examples, that the modal content of supposed a posteriori necessities is more complicated than the Kripkean line suggests. We will see that further research is needed concerning the a priori principles underlying all a posteriori necessities. In the course of this analysis it will emerge that the modal content of a posteriori necessities can be best described in terms of a Finean (...) conception of modality – by giving essences priority over modality. The upshot of this is that we might be able to establish the necessity of certain supposed a posteriori necessities by a priori means. (shrink)

Volume 41, Issue 1, February 2020, Page 97-100.

This is identical with the first edition (see 21: 2716) except for the addition of a Supplement containing 5 previously published articles and the bringing of the bibliography (now 73 items) up to date. The 5 added articles present clarifications or modifications of views expressed in the first edition. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

Recently it has become almost the received wisdom in certain quarters that Kripke models are appropriate only for something like metaphysical modalities, and not for logical modalities. Here the line of thought leading to Kripke models, and reasons why they are no less appropriate for logical than for other modalities, are explained. It is also indicated where the fallacy in the argument leading to the contrary conclusion lies. The lessons learned are then applied to the question of the status of (...) the formula. (shrink)

In this article I contrast two opposing forms of essentialism, definitional and transcendental versus productivist and historical, and trace both forms back to Kripke's Naming and Necessity (1980). Definitional essentialism, as developed by Fine, centers on kind-membership. Historical essentialism, as anticipated by Prior and developed by Almog, puts origin at its center. The article focuses on the fundamentally distinct manners in which these two views handle the necessity of origin thesis. In the final section of the article, inspired (...) by a Nietzschean genealogical methodology, I pursue a naturalization strategy and conclude that rather than origin being necessary, it is essentialist necessity that reduces to origin. (shrink)

What is this discipline called history of philosophy? What standards are relevant to its assessment? There aren’t single, straightforward answers to these quest.

Philosophers since Aristotle have traditionally held that impossibilities make up the nature of logic. Sanford Shieh investigates an important but underexplored break with this tradition: Frege and Russell questioned whether there really are such things as possibilities or necessities, and sought the foundations of logic elsewhere.

God is often conceived as a necessary being, but if gratuitous evil is even possible, then God cannot be necessary. Two arguments are developed that the possibility of gratuitous evil is more probable than divine necessity. Thus, probably, it is impossible for God to be a necessary being. The main argument is then followed with some reflection on what this conclusion means for philosophical theism.

This article investigates the prospect of giving de dicto- and de re-necessity a uniform treatment. The historical starting point is a puzzle raised by Aristotle's claim, advanced in one of the modal chapters of his Prior Analytics, that universally privative apodeictic premises simply convert. As regards the Prior and the Posterior Analytics, the data suggest a representation of propositions of the type in question by doubly modally qualified formulae of modal predicate logic that display a necessity operator in (...) two distinct positions. Can the N-operator occurring in these positions be given a unified semantical treatment (which would justify dispensing with a notational differentiation)? A positive answer, based on a suitably shaped truth condition for N-formulae, is given, and is supported in the final section with an alternative proof theoretically based conception of a property's essential belonging to an individual. (shrink)

Many logicians have tried to formalize a modal logic from the Prior Analytics, but the general view is that Aristotle has failed to offer a consistent modal logic there. This paper explains that Aristotle is not interested in modal logic as such. Modalities for him pertain to the relations of predication, without challenging the assertoric system of deductions simpliciter. Thus, demonstrations or dialectical deductions have modal predicates and yet are still deductions simpliciter. It is a matter of distinguishing inferential (...) class='Hi'>necessity that applies to every deduction from the modal predicates in the two premises and conclusion. The modality of demonstrations can be either necessary or possible. The necessity is predicative, i.e., independent of inferential necessity. While the possible demonstration challenges the predicative necessity of the necessary demonstration, it preserves the inferential necessity of the deduction simpliciter. (shrink)

"Analytic philosophy has leveled many challenges to Kant's ascription of necessary properties and relations to objects in his Critique of Pure Reason. Some of these challenges can be answered, it is argued here, largely in terms of techniques belonging to analytic philosophy itself, in particular, to its philosophy of language. This Kantian response is the primary objective of this book. It takes the form of a compromise between the real existence of the objects that we can intuit and that get (...) our knowledge started - dubbed initiators - and the ideality of the necessary properties and relations that Kant ascribes to our sensible representations of initiators, which he entitles appearances. Whereas the real existence of initiators is independent of us and our senses, the necessity of these properties and relations of appearances is due to their origins in the mind."--BOOK JACKET. (shrink)

A possible world semantics for standard modal languages is presented, where the valuation functions are allowed to be partial, the truth--functional connectives are interpreted according to weak Kleene matrices, and the necessity operator is given a "weak" interpretation. Completeness and incompleteness results for some (axiomatic) systems are then established. Extensions of these modal logics in which figure "statability" operators are also examined.

The word "modem" in the title of this book refers primarily to post-medieval discussions, but it also hints at those medieval mo dal theories which were considered modem in contradistinction to ancient conceptions and which in different ways influenced philosophical discussions during the early modem period. The me dieval developments are investigated in the opening paper, 'The Foundations of Modality and Conceivability in Descartes and His Predecessors', by Lilli Alanen and Simo Knuuttila. Boethius's works from the early sixth century belonged (...) to the sources from which early medieval thinkers obtained their knowledge of ancient thought. They offered extensive discus sions of traditional modal conceptions the basic forms of which were: (1) the paradigm of possibility as a potency striving to realize itself; (2) the "statistical" interpretation of modal no tions where necessity means actuality in all relevant cases or omnitemporal actuality, possibility means actuality in some rel evant cases or sometimes, and impossibility means omnitemporal non-actuality; and (3) the "logical" definition of possibility as something which, being assumed, results in nothing contradic tory. Boethius accepted the Aristotelian view according to which total possibilities in the first sense must prove their met tle through actualization and possibilities in the third sense are assumed to be realized in our actual history. On these presump tions, all of the above-mentioned ancient paradigms imply the Principle of Plenitude according to which no genuine possibility remains unrealized. (shrink)

On Anselmian theism, God is, amongst other things, a necessary being. On genuine modal realism, possible worlds are maximal mereological sums of spatiotemporally connected individuals. I argue in this paper that AT and GMR are either incompatible or their conjunction leads to—amongst other things—modal collapse. Specifically, I argue: regardless of whether God is concrete or abstract, His necessary existence either is inconsistent with AT-GMR or it leads to, amongst other things, modal collapse for AT-GMR. I conclude the paper by contending (...) that, if I am correct, the ATist will have an argument against the truth of GMR, and the GMRist will have an argument against the truth of AT. (shrink)

A prevailing thought is that generics have a covert modal operator at logical form. I claim that if this is right, the covert generic modality is a weak necessity modal. In this paper, I pr...

Non-classical generalizations of classical modal logic have been developed in the contexts of constructive mathematics and natural language semantics. In this paper, we discuss a general approach to the semantics of non-classical modal logics via algebraic representation theorems. We begin with complete lattices L equipped with an antitone operation ¬ sending 1 to 0, a completely multiplicative operation ◻, and a completely additive operation ◊. Such lattice expansions can be represented by means of a set X together with binary relations (...) ⊲, R, and Q, satisfying some first-order conditions, used to represent (L,¬), ◻, and ◊, respectively. Indeed, any lattice L equipped with such a ¬, a multiplicative ◻, and an additive ◊ embeds into the lattice of propositions of a frame (X,⊲,R,Q). Building on our recent study of "fundamental logic", we focus on the case where ¬ is dually self-adjoint (a≤¬b implies b≤¬a) and ◊¬a≤¬◻a. In this case, the representations can be constrained so that R=Q, i.e., we need only add a single relation to (X,⊲) to represent both ◻ and ◊. Using these results, we prove that a system of fundamental modal logic is sound and complete with respect to an elementary class of bi-relational structures (X,⊲,R). (shrink)

The chapter defends an evolutionary explanation of modal knowledge from knowledge of counterfactual conditionals. Knowledge of counterfactuals is evolutionarily useful, as it enables us to learn from mistakes. Given the standard semantics for counterfactuals, there are several equivalences between modal claims and claims involving counterfactuals that can be used to explain modal knowledge. Timothy Williamson has suggested an explanation of modal knowledge that draws on the equivalence of ‘Necessarily p’ with ‘If p were false, a contradiction would be the case’. (...) He postulates a cognitive process that draws on this equivalence and that is supposed to underlie our modal judgements. The existence of this cognitive process would, however, have consequences that conflict with results from empirical psychology. The chapter argues that the equivalence of ‘Necessarily p’ with ‘For all q, if q were true then p would be true’ should instead be used to explain knowledge of necessity. This explanation requires giving an account of how we know truths of the form ‘For all q, if q were true then p would be true’. In order to provide such an account, the chapter draws on a different suggestion by Williamson about knowledge of generalizations. According to this suggestion, we come to know truths of the form ‘All Fs are G’ by imagining a generic F and judging that it is G. Applied to our case, the suggestion would be that we come to know that p is counterfactually implied by all propositions (and hence that p is necessary) by entertaining a generic proposition and judging that it counterfactually implies p. It would even suffice to entertain a generic possible proposition and judge that it counterfactually implies p, for it can be shown that the claim ‘For all possible q, if q were true then p would be true’ is equivalent to the original claim ‘For all q, if q were true then p would be true’ and hence is equivalent to ‘Necessarily p’. It might seem that, from an evolutionary perspective, probabilistic reasoning is just as useful as reasoning involving counterfactuals. The chapter argues, however, that this would not undermine the envisaged explanation of modal knowledge. The chapter concludes by suggesting avenues of empirical research that might shed light on the cognitive processes that actually underlie our evaluations of modal claims and on the relation between these processes and those involved in counterfactual reasoning. The results of such empirical research would be highly relevant epistemologically, since they will ultimately determine which (if any) equivalence between modal claims and claims involving counterfactuals should be used to explain our modal knowledge. (shrink)

In the past three decades there has been a rapid development of the formal machinery for modal logic. Quantified modal logic has developed along with a semantics and model theory that is appropriate to it. With this technical development there has been relatively little discussion of what modality is all about. There are two fundamental questions that have gone unanswered. First, to what does necessity amount? Is this a new logical notion, or is it something that can be further (...) analyzed in terms of other notions that we already have at our disposal? The second question is what makes truths involving necessity true? What is their ontological grounding in the world? This essay is directed at the first of these questions. ;There are three possible reductions of metaphysical modality. First, there is the reduction suggested by the semantics for modal logic: a reduction in terms of possible worlds. Second, there is the reduction in terms of cognition. What is possible is what is conceivable. Third, there is the reduction in terms of language. Necessities arise from the structures of language and/or language use. ;I argue that none of these is successful. All of them suffer either from presupposing some form of metaphysical necessity in the reductive base, rendering them circular and not truly reductive, or they do not do justice to the modality being reduced. ;Since necessity is not reducible to any non-modal features of the world, we need to determine whether we ought to reject it as unacceptable on this basis, or whether we ought to retain it, but treat is as a new primitive that is introduced into a philosophical or logical theory. I urge the latter course is the one that we ought to take because without it too many things will likewise be deemed unacceptable. Causal necessity and explanation, normally accepted theories or knowledge and perception, logic and logical validity, and one common manner of distinguishing sets from properties will be deemed unacceptable if de re necessity is unacceptable. All of these presuppose de re metaphysical necessity in some way. I conclude that de re metaphysical necessity ought to be retained in our theory as primitive, unanalyzable notion. (shrink)

This book sets out a Kant-inspired theory of modality, driven by a methodology which takes seriously questions about the function of modal judgment as a guide to a metaphysics of modality. It argues that we need logical modal concepts as a condition on our ability to think, and metaphysical modal concepts as a condition on our ability to think objectively. Concordant with this, it argues that logical necessity has its source in the laws of thought and that metaphysical (...) class='Hi'>necessity is relative to conditions on objective thought. This this account of metaphysical necessity, which is termed “Modal Transcendentalism”, is then further developed, covering questions concerning necessary and contingent existence, de re necessity, essentialism, and modal epistemology. (shrink)

The Master Argument, recorded by Epictetus, indicates that Diodorus had deduced a contradiction from the conjoint assertion of three propositions. The Argument, which has to do with necessity and contingency and therefore with freedom, has attracted the attention of logicians above all. There have been many attempts at reconstructing it in logical terms, without excessive worry about historical plausibility and with the foregone conclusion that it was sophistic since it directly imperilled our common sense notion of freedom. This text (...) takes exception to recent tradition, translating the propositions into logical terms. The propositions figuring in The Master Argument are interpreted in terms of temporal modal logic where both the modalities and the statements they govern have chronological indices. This means that the force of the argument comes not from purely logical or modal considerations, but from our experience of time. (shrink)

Summary: The paper provides an argument for modal primitivism, the view that necessity is not defined and is therefore part of the structure of reality. It then raises the explanation-challenge for primitivists: how can modal truths be explained by hyper-intensional truths, if necessity is not defined in terms of hyper-intensional phenomena? To address the challenge, the paper introduces 'sophisticated modal primitivism' which gives a substantive analysis of the notion of a 'source of necessity'. The final part of (...) the paper offers some applications of that novel piece of ideology. (shrink)