Vagueness manifests itself (among other things) in our inability to find boundaries to the extension of vague predicates. A semantic theory of vagueness plans to justify this inability in terms of the vague semantic rules governing language and thought. According to a supporter of semantic theory, the inability to find such a boundary is not dependent on epistemic limits and an omniscient being like God would be equally unable. Williamson (Vagueness, 1994 ) argued that cooperative omniscient beings adequately instructed would (...) find a precise boundary in a sorites series and that, for this reason, the semantic theory misses its target, while Hawthorne (Philosophical Studies 122:1–25, 2005 ) stood with the semantic theorists and argued that the linguistic behaviour of a cooperative omniscient being like God would clearly demonstrate that he does not find a precise boundary in the sorites series. I argue that Hawthorne’s definition of God’s cooperative behaviour cannot be accepted and that, contrary to what has been assumed by both Williamson and Hawthorne, an omniscient being like God cannot be a cooperative evaluator of a semantic theory of vagueness. (shrink)

I present some puzzling cases regarding knowledge and its relation to rational credence. They seem to entail a failure of an apparently correct principle: if S knows P, then the epistemic justi...

The primary appeal of stakeholder theory in business ethics derives from its promise to help solve two large and often morally difficult problems: (1) how to manage people fairly and efficiently and (2) how to determine the extent of a firm's moral responsibilities beyond its obligations to enhance its profits and economic value. This article investigates a variety of conceptual quandaries that stakeholder theory faces in addressing these two general problems. It argues that these quandaries pose intractable obstacles for stakeholder (...) theory which prevent it from delivering on its large promises. Acknowledging that various versions of stakeholder theory have made a contribution in elucidating the complex nature of firms and business decision making, the article argues that it is time to move on. More precise explications of the nature of modern firms focusing on the application of basic moral principles to different business contexts and situations are likely to prove more accurate and useful. (shrink)

The notorious problem of the many makes it difficult to resist the conclusion that almost coincident with any ordinary object are a vast number of near-indiscernible objects. As Unger was aware in his presentation of the problem, this abundance raises a concern as to how—and even whether—we achieve singular thought about ordinary objects. This paper presents, clarifies, and defends a view which reconciles a plenitudinous conception of ordinary objects with our having singular thoughts about those objects. Indeed, this strategy has (...) independent application in the case of singular thoughts about other putatively ‘abundant’ phenomena, such as locations or lumps of matter. In essence, singular thought-vehicles need not express just one singular content. If there are many objects, one’s singular thought-vehicle may express as many thought-contents. (shrink)

The appearance in 1945 of the idea of the open texture of empirical concepts, which anticipated Friedrich Waismann’s thesis of a many-level-structure of language, led to a re-evaluation of “context”. It widens the sense of context that we are accustomed to mentioning as being Wittgenstein’s conception of meaning in his later philosophy. The new idea Waismann brought into the landscape is how to “clarify the context”, which is in a way a very non-Wittgensteinian question as well as an “explanation of (...) context”, where open texture plays a key role. But despite the amount of literature about open texture, this idea of Waismann is still not properly understood. Open texture must be situated as an obstacle to exhaustiveness of definition for internal reasons not only because of unforeseen conditions that could always arise in the future, but also by virtue of an a priori aspect of the texture of concepts. Thus, the main goal of this paper is to propose an interpretation of open texture as an immanent property of a concept, that is, as something that is underlying its nature. (shrink)

Vague predicates, those that exhibit borderline cases, pose a persistent problem for philosophers and logicians. Although they are ubiquitous in natural language, when used in a logical context, vague predicates lead to contradiction. This paper will address a question that is intimately related to this problem. Given their inherent imprecision, why do vague predicates arise in the first place? I discuss a variation of the signaling game where the state space is treated as contiguous, i.e., endowed with a metric that (...) captures a similarity relation over states. This added structure is manifested in payoffs that reward approximate coordination between sender and receiver as well as perfect coordination. I evolve these games using a variation of Herrnstein reinforcement learning that better reflects the generalizing learning strategies real-world actors use in situations where states of the world are similar. In these simulations, signaling can develop very quickly, and the signals are vague in much the way ordinary language predicates are vague—they each exclusively apply to certain items, but for some transition period both signals apply to varying degrees. Moreover, I show that under certain parameter values, in particular when state spaces are large and time is limited, learning generalization of this sort yields strategies with higher payoffs than standard Herrnstein reinforcement learning. These models may then help explain why the phenomenon of vagueness arises in natural language: the learning strategies that allow actors to quickly and effectively develop signaling conventions in contiguous state spaces make it unavoidable. (shrink)

Two of the main contenders in the debate about personal persistence over time are the neo-Lockean psychological continuity view and animalism as defended by Olson and Snowdon. Both are wrong. The position I shall argue for, which I call, following Olson, the hybrid view, takes psychological continuity as a sufficient but, pace the neo-Lockeans, not necessary condition for personal persistence. It sides with the animalist in allowing that mere biological continuity is also sufficient. So I am, in a sense, a (...) psychological continuity theorist. But I am also in a sense, a biological theorist. (shrink)

There’s an argument around from so-called “linguistic theories of vagueness”, plus some relatively uncontroversial considerations, to powerful metaphysical conclusions. David Lewis employs this argument to support the mereological principle of unrestricted composition, and Theodore Sider employs a similar argument not just for unrestricted composition but also for the doctrine of temporal parts. This sort of argument could be generalised, to produce a lot of other less palatable metaphysical conclusions. However, arguments to Lewis’s and Sider’s conclusions on the basis of considerations (...) about vagueness are uncompelling, even if we accept the crucial premises about vagueness. And a good thing too, since the generalised form of the argument would prove far too much. (shrink)

A lot of good philosophy is done in the armchair, but is nevertheless a posteriori. This paper clarifies and then defends that claim. Among the a posteriori activities done in the armchair are assembling and evaluating commonplaces; formulating theoretical alternatives; and integrating well-known past a posteriori discoveries. The activity that receives the most discussion, however, is the application of theoretical virtues to choose philosophical theories: the paper argues that much of this is properly seen as a posteriori.

The surviving sources on the Stoic theory of division reveal that the Stoics, particularly Chrysippus, believed that bodies, places and times were such that all of their parts themselves had proper parts. That is, bodies, places and times were composed of gunk. This realisation helps solve some long-standing puzzles about the Stoic theory of mixture and the Stoic attitude to the present.

In this paper, I raise an objection to Philip Goff’s “Revelation Thesis” as articulated in his Consciousness and Fundamental Reality. In Sect. 1 I present the Revelation Thesis in the context of Goff’s broader defence of pan-psychism. In Sect. 2 I argue that the Revelation Thesis entails the identity of indiscriminable phenomenal properties. In Sect. 3 I argue that the identity of indiscriminable phenomenal properties is false. The upshot is that the Revelation Thesis is false.

The Rachels–Temkin spectrum arguments against the transitivity of better than involve good or bad experiences, lives, or outcomes that vary along multiple dimensions—e.g., duration and intensity of pleasure or pain. This paper presents variations on these arguments involving combinations of good and bad experiences, which have even more radical implications than the violation of transitivity. These variations force opponents of transitivity to conclude that something good is worse than something that isn’t good, on pain of rejecting the good altogether. That (...) is impossible, so we must reject the spectrum arguments. (shrink)

On a widespread naturalist view, the meanings of mathematical terms are determined, and can only be determined, by the way we use mathematical language—in particular, by the basic mathematical principles we’re disposed to accept. But it’s mysterious how this can be so, since, as is well known, minimally strong first-order theories are non-categorical and so are compatible with countless non-isomorphic interpretations. As for second-order theories: though they typically enjoy categoricity results—for instance, Dedekind’s categoricity theorem for second-order PA and Zermelo’s quasi-categoricity (...) theorem for second-order ZFC—these results require full second-order logic. So appealing to these results seems only to push the problem back, since the principles of second-order logic are themselves non-categorical: those principles are compatible with restricted interpretations of the second-order quantifiers on which Dedekind’s and Zermelo’s results are no longer available. In this paper, we provide a naturalist-friendly, non-revisionary solution to an analogous but seemingly more basic problem—Carnap’s Categoricity Problem for propositional and first-order logic—and show that our solution generalizes, giving us full second-order logic and thereby securing the categoricity or quasi-categoricity of second-order mathematical theories. Briefly, the first-order quantifiers have their intended interpretation, we claim, because we’re disposed to follow the quantifier rules in an open-ended way. As we show, given this open-endedness, the interpretation of the quantifiers must be permutation-invariant and so, by a theorem recently proved by Bonnay and Westerståhl, must be the standard interpretation. Analogously for the second-order case: we prove, by generalizing Bonnay and Westerståhl’s theorem, that the permutation invariance of the interpretation of the second-order quantifiers, guaranteed once again by the open-endedness of our inferential dispositions, suffices to yield full second-order logic. (shrink)

In Knowledge and Its Limits Timothy Williamson argues against the luminosity of phenomenal states in general by way of arguing against the luminosity of feeling cold, that is, against the view that if one feels cold, one is at least in a position to know that one does. In this paper I consider four strategies that emerge from his discussion, and argue that none succeeds.

I develop a novel argument against the claim that ordinals are sets. In contrast to Benacerraf’s antireductionist argument, I make no use of covert epistemic assumptions. Instead, my argument uses considerations of ontological dependence. I draw on the datum that sets depend immediately and asymmetrically on their elements and argue that this datum is incompatible with reductionism, given plausible assumptions about the dependence profile of ordinals. In addition, I show that a structurally similar argument can be made against the claim (...) that cardinals are sets. (shrink)

Epistemicism is the view that seemingly vague predicates are not in fact vague. Consequently, there must be a sharp boundary between a man who is bald and one who is not bald. Although such a view is often met with incredulity, my aim is to provide a defense of epistemicism in this essay. My defense, however, is backhanded: I argue that the formal commitments of epistemicism are the result of good practical reasoning, not metaphysical necessity. To get to that conclusion, (...) I spend most of the essay arguing that using a formal system like classical logic to manage seemingly vague situations requires practical principles to mediate between the formalism and what it aims to represent. (shrink)

Intellectualists about knowledge how argue that knowing how to do something is knowing the content of a proposition (i.e, a fact). An important component of this view is the idea that propositional knowledge is translated into behavior when it is presented to the mind in a peculiarly practical way. Until recently, however, intellectualists have not said much about what it means for propositional knowledge to be entertained under thought's practical guise. Carlotta Pavese fills this gap in the intellectualist view by (...) modeling practical modes of thought after Fregean senses. In this paper, I take up her model and the presuppositions it is built upon, arguing that her view of practical thought is not positioned to account for much of what human agents are able to do. (shrink)

I present three invented languages, in order to support a claim that vagueness and demonstrativity are related. One of them handles vagueness like English handles demonstratives, the second handles demonstratives like English handles vagueness, and the third combines the resources of the first two. The argument depends on the claim that all three can be learned and used by anyone who can speak English.

This paper intends to further the understanding of the formal properties of (higher-order) vagueness by connecting theories of (higher-order) vagueness with more recent work in topology. First, we provide a “translation” of Bobzien's account of columnar higher-order vagueness into the logic of topological spaces. Since columnar vagueness is an essential ingredient of her solution to the Sorites paradox, a central problem of any theory of vagueness comes into contact with the modern mathematical theory of topology. Second, Rumfitt’s recent topological reconstruction (...) of Sainsbury’s theory of prototypically defined concepts is shown to lead to the same class of spaces that characterize Bobzien’s account of columnar vagueness, namely, weakly scattered spaces. Rumfitt calls these spaces polar spaces. They turn out to be closely related to Gärdenfors’ conceptual spaces, which have come to play an ever more important role in cognitive science and related disciplines. Finally, Williamson’s “logic of clarity” is explicated in terms of a generalized topology (“locology”) that can be considered an alternative to standard topology. Arguably, locology has some conceptual advantages over topology with respect to the conceptualization of a boundary and a borderline. Moreover, in Williamson’s logic of clarity, vague concepts with respect to a notion of a locologically inspired notion of a “slim boundary” are (stably) columnar. Thus, Williamson’s logic of clarity also exhibits a certain affinity for columnar vagueness. In sum, a topological perspective is useful for a conceptual elucidation and unification of central aspects of a variety of contemporary accounts of vagueness. (shrink)

Suppose you're unable to discriminate the colors of two objects. According to the triangulation view, their colors might nonetheless look different to you, and that's something you can discover as a result of further comparisons. The primary motivation for this view is its apparent ability to solve a puzzle involving a series of pairwise indiscriminable objects. I argue that, due to visual noise, the triangulation view doesn't really solve the puzzle.

This paper offers an analysis of metalinguistic comparatives such as more dumb than crazy in which they differ from ordinary comparatives in the scale on which they compare: ordinary comparatives use scales lexically determined by particular adjectives, but metalinguistic ones use a generally-available scale of imprecision or ‘pragmatic slack’. To implement this idea, I propose a novel compositional implementation of the Lasersohnian pragmatic-halos account of imprecision—one that represents clusters of similar meanings as Hamblin alternatives. In the theory that results, existential (...) closure over alternatives mediates between alternative-sets and meanings in which imprecision has been resolved. I then articulate a version of this theory in which the alternatives are not related meanings but rather related utterances, departing significantly from Lasersohn’s original conception. Although such a theory of imprecision is more clearly ‘metalinguistic’, the evidence for it from metalinguistic comparatives in English is surprisingly limited. The overall picture that emerges is one in which the grammatical distinction between ordinary and metalinguistic comparatives tracks the independently motivated distinction between vagueness and imprecision. (shrink)

This paper deals with the possibility of faultless disagreement in law. It does this by looking to other spheres in which faultless disagreement appears to be possible, mainly in matters of taste and ethics. Three possible accounts are explored: the realist account, the relativist account, and the expressivist account. The paper tries to show that in the case of legal disagreements, there is a place for an approach that can take into account our intuitions in the sense that legal disagreements (...) are genuine and at times faultless. (shrink)

In this paper, I develop and motivate a novel formulation of the safety condition in terms of etiological proper function. After testing this condition against the most pressing objections to safety-theoretic accounts of knowledge in the literature, my conclusion will be the following: once safety is suitably understood in terms of etiological proper function, it stands a better chance as the right anti-Gettier condition on knowledge.

Those inclined to believe in the existence of propositions as traditionally conceived might seek to reduce them to some other type of entity. However, parsimonious propositionalists of this type are confronted with a choice of competing candidates – for example, sets of possible worlds, and various neo-Russellian and neo-Fregean constructions. It is argued that this choice is an arbitrary one, and that it closely resembles the type of problematic choice that, as Benacerraf pointed out, bedevils the attempt to reduce numbers (...) to sets – should the number 2 be identified with the set Ø or with the set Ø, Ø? An “argument from arbitrary identification” is formulated with the conclusion that propositions (and perhaps numbers) cannot be reduced away. Various responses to this argument are considered, but ultimately rejected. The paper concludes that the argument is sound: propositions, at least, are sui generis entities. (shrink)

Abstract: Despite all the critical scrutiny they have received recently, contextualist views in philosophy are still not well understood. Neither contextualists nor their opponents have been entirely clear about what contextualist theses amount to and what they are based on. In this article I show that there are actually two kinds of contextualist view that rest on two very different semantic phenomena, namely, semantic incompleteness and semantic indeterminacy . I explain how contextualist approaches can be used to dissolve certain debates (...) in philosophy. According to such approaches, the same philosophical thesis can be correctly endorsed in some contexts and correctly denied in others: it is thus pointless to seek a context-independent solution to debates about this thesis. My purpose is not to defend particular contextualist views but to lay out the general framework on which they rest: this allows us to see more clearly the similarities and differences among contextualist views defended in various areas of philosophy. (shrink)

Scott Soames argues that consideration of the practice of legal judgement gives us good reason to favor the partial-definition/context-sensitive theory of vagueness against epistemicism. Despite the fact that the value of power-delegation through vagueness is evidenced in practice, Soames says, epistemicism cannot account for it theoretically, while the partial-definition/context-sensitive theory is capable of it. In this paper, I examine the two possible arguments against epistemicism that can be extracted from Soames’s account: (i) an argument based on unknown obligations, and (ii) (...) an argument based on power-delegation through vagueness. The first argument tries to convince us that, as based on epistemicism, the law has already decided the borderline cases, so that judges have obligatory decisions even in such cases: therefore epistemicism is inconsistent with the discretion of judges in borderline cases. I show that even if we sympathize with Soames’s intuitions concerning the legal practice, the argument he offers is not conclusive since it is either invalid, unsound, or paradoxical. The second argument holds that only the gaps which the partial-definition/context-sensitive theory predicts give judges the possibility of lawmaking in borderline cases. However, by categorizing the vague laws as imperfect laws, the judges can claim the right of lawmaking without any need to refer to gaps in the law. By neutralizing these arguments, I argue that epistemicism is able to explain the phenomena just as well as the partial-definition/context-sensitive theory. (shrink)

Several philosophers offer explanations of linguistic vagueness by appealing to the referential context-dependence of vague terms. Timothy Williamson argues pre-emptively that any such approach must fail, on the grounds that context-dependence is neither necessary nor sufficient for vagueness. He supports this claim, in turn, by example. This paper argues that his examples fail to show that context-dependence is either unnecessary or insufficient for vagueness, and hence that he has failed by his own lights to show that it cannot explain vagueness.

Uncertainty and vagueness/imprecision are not the same: one can be certain about events described using vague predicates and about imprecisely specified events, just as one can be uncertain about precisely specified events. Exactly because of this, a question arises about how one ought to assign probabilities to imprecisely specified events in the case when no possible available evidence will eradicate the imprecision (because, say, of the limits of accuracy of a measuring device). Modelling imprecision by rough sets over an approximation (...) space presents an especially tractable case to help get one’s bearings. Two solutions present themselves: the first takes as upper and lower probabilities of the event X the (exact) probabilities assigned X ’s upper and lower rough-set approximations; the second, motivated both by formal considerations and by a simple betting argument, is to treat X ’s rough-set approximation as a conditional event and assign to it a point-valued (conditional) probability. (shrink)

According to one account, vagueness is "metaphysical." The friend of metaphysical vagueness believes that, for some object and some property, there can be no determinate fact of the matter whether that object exemplifies that property. A second account maintains that vagueness is due only to ignorance. According to the epistemic account, vagueness is explained completely by and is nothing over and above our not knowing some relevant fact or facts. These are the minority views. The dominant position maintains that there (...) is a third possible variety of vagueness, linguistic vagueness. And, it goes on to insist, all vagueness is of this third variety. I shall argue, however, that linguistic vagueness is not a third variety of vagueness. Either it is a species of metaphysical vagueness or a kind of ignorance. And this, I argue, makes trouble for the claim that all vagueness is linguistic. (shrink)

In this paper I develop a semantic theory of vagueness that is immune to worries regarding the use of precise mathematical tools. I call this view semantic quietism. This view has the advantage of being clearly compatible with the phenomenon of vagueness. The cost is that it cannot capture every robust semantic fact.

It is notoriously difficult to model the range of application of vague predicates relative to a suitable sorites series. In this paper I offer some critical remarks against an interesting view that has received little attention in the literature. According to it, the sharp cut-offs we find in our semantic models are just artifacts of the theory, and, as such, they are harmless. At the end I discuss a contextualist view that, at a cost, may be able to get around (...) the problems related to sharp cut-offs incurred in by other theories of vagueness. Es sumamente difícil modelar el rango de aplicación de predicados vagos relativo a una serie sorites apropiada. En este artículo ofrezco algunos comentarios críticos en contra de una postura interesante que ha recibido poca atención en la literatura. De acuerdo con ella, los cortes precisos que encontramos en modelos semánticos son simplemente artefactos de la teoría, y, como tales, son inofensivos. Al final del artículo discuto una postura contextualista que, no sin sacrificios, podría ser capaz de evadir los problemas relacionados con cortes precisos que otras teorías de la vaguedad poseen. (shrink)

Entities of many kinds, not just material things, have been credited with parts. Armstrong , for example, has taken propositions and properties to be parts of their conjunctions, sets to be parts of sets that include them, and geographical regions and events to be parts of regions and events that contain them. The justification for bringing all these diverse relations under a single ‘part–whole’ concept is that they share all or most of the formal features articulated in mereology . But (...) the concept has also prompted an ontological thesis that has been expressed in various ways: that wholes are ‘no ontological addition’ to their parts ; that to list both a whole and its parts is ‘double counting’; and that there is ‘no more’ to a whole than its parts: for example, that there is no more to a conjunction than the conjuncts that are its parts, and whose truth or falsity determines whether it is true or false. For brevity, I shall express the thesis in the last of these ways, as the claim that entities with parts are ‘nothing but’ those parts. (shrink)

The principle of Summation, which is a technically sharpened version of the familiar claim that a whole is a sum of its parts, is presented by Peter van Inwagen as a trivial truth. I argue to the contrary, that it is incompatible with the natural assumption that a whole may gain or lose parts non-instantaneously. For, as I show, the latter assumption implies that something can be determinately a whole without being determinately a sum of parts, and this, in turn, (...) indicates the falsity of Summation. I point out that the tension between Summation and the possibility of non-instantaneous gain or loss of parts compels us to rethink the relations between the concepts of whole and sum, and may have far reaching consequences for the mereology of physical objects. (shrink)

Supervaluational treatments of vagueness are currently quite popular among those who regard vagueness as a thoroughly semantic phenomenon. Peter Unger's 'problem of the many' may be regarded as arising from the vagueness of our ordinary physical-object terms, so it is not surprising that supervaluational solutions to Unger's problem have been offered. I argue that supervaluations do not afford an adequate solution to the problem of the many. Moreover, the considerations I raise against the supervaluational solution tell also against the solution (...) to the problem of the many which is suggested by adherents of the epistemic theory of vagueness. (shrink)

That reference is inscrutable is demonstrated, it is argued, not only by W. V. Quine's arguments but by Peter Unger's "Problem of the Many." Applied to our own language, this is a paradoxical result, since nothing could be more obvious to speakers of English than that, when they use the word "rabbit," they are talking about rabbits. The solution to this paradox is to take a disquotational view of reference for one's own language, so that "When I use 'rabbit,' I (...) refer to rabbits" is made true by the meaning of the word "refer." The reference relation is extended to other languages by translation. The explanation for this peculiarly egocentric conception of semantics-questions of others' meanings are settled by asking what I mean by words of my language-is to be found in our practice of predicting and explaining other people's behavior by empathetic identification. I understand other people's behavior by asking what I would do in their place. (shrink)

The problem of artificial precision is a major objection to any theory of vagueness based on real numbers as degrees of truth. Suppose you are willing to admit that, under sufficiently specified circumstances, a predication of “is red” receives a unique, exact number from the real unit interval [0, 1]. You should then be committed to explain what is it that determines that value, settling for instance that my coat is red to degree 0.322 rather than 0.321. In this note (...) I revisit the problem in the important case of Łukasiewicz infinite-valued propositional logic that brings to the foreground the rôle of maximally consistent theories. I argue that the problem of artificial precision, as commonly conceived of in the literature, actually conflates two distinct problems of a very different nature. (shrink)

Motivated by weaknesses with traditional accounts of logical epistemology, considerable attention has been paid recently to the view, known as anti-exceptionalism about logic, that the subject matter and epistemology of logic may not be so different from that of the recognised sciences. One of the most prevalent claims made by advocates of AEL is that theory choice within logic is significantly similar to that within the sciences. This connection with scientific methodology highlights a considerable challenge for the anti-exceptionalist, as two (...) uncontentious claims about scientific theories are that they attempt to explain a target phenomenon and prove their worth through successful predictions. Thus, if this methodological AEL is to be viable, the anti-exceptionalist will need a reasonable account of what phenomena logics are attempting to explain, how they can explain, and in what sense they can be said to issue predictions. This paper makes sense of the anti-exceptionalist proposal with a new account of logical theory choice, logical predictivism, according to which logics are engaged in both a process of prediction and explanation. (shrink)

This paper offers a rejoinder to an argument by Schiffer against semantic accounts of vagueness (typically relying on supervaluationist techniques) based on indirect discourse. The argument, as far as I know original with Schiffer, occurs in “Two Issues of Vagueness” (Schiffer 1998). It is not addressed at supervaluationism as such, but at the philosophical account of vagueness which typically relies on it. Supervaluationism is not by itself a theory, but a logical technique with several applications. In one such application, supervaluationism (...) serves to alleviate a tension between, on the one hand, the rejection of bivalence for some utterances which characterizes what I take to be the correct view on vagueness (vagueness as semantic indecision – ‘VSI’ henceforth –, to put it in the terms of a well-known defender of the view, David Lewis), and, on the other, well-established facts about the semantics of logical expressions. I will address Schiffer’s argument by putting forward some considerations on the concept of de re thoughts which I take to undermine it. These considerations are not ad hoc, but highly germane to VSI; or so I will try to show. (shrink)

I explore the logic of the conditional, using credence judgments to argue against Duality and in favor of Conditional Excluded Middle. I then explore how to give a theory of the conditional which validates the latter and not the former, developing a variant on Kratzer (1981)'s restrictor theory, as well as a proposal which combines Stalnaker (1968)'s theory of the conditional with the theory of epistemic modals I develop in Mandelkern 2019a. I argue that the latter approach fits naturally with (...) a conception of conditionals as referential devices which allow us to talk about particular worlds. (shrink)

The thin red line ( TRL ) is a theory about the semantics of future-contingents. The central idea is that there is such a thing as the ‘actual future’, even in the presence of indeterminism. It is inspired by a famous solution to the problem of divine foreknowledge associated with William of Ockham, in which the freedom of agents is argued to be compatible with God’s omniscience. In the modern branching time setting, the theory of the TRL is widely regarded (...) to suffer from several fundamental problems. In this paper we propose several new TRL semantics, each with differing degrees of success. This leads up to our final semantics, which is a cross between the TRL and supervaluationism. We discuss the notions of truth, validity and semantic consequence which result from our final semantics, and demonstrate some of its pleasing results. This account, we believe, answers the main objection in the literature, and thus places the TRL on the same level as any other competing semantics for future contingents. (shrink)

Timothy Williamson claims that margin for error principles govern all cases of inexact knowledge. I show that this claim is unfounded: there are cases of inexact knowledge where Williamson’s argument for margin for error principles does not go through. The problematic cases are those where the value of the relevant parameter is fixed across close cases. I explore and reject two responses to my objection, before concluding that Williamson’s account of inexact knowledge is not compelling.

Timothy Williamson's response to the question why we cannot know where the sharp boundaries marked by vague terms lie involves the claim that vague terms are unstable. Several theorists would not accept this claim, and it is tempting to think that this gives them a good objection to Williamson. By clarifying the structure of Williamson's response to the title question, I show that this objection is wrong-headed, and reveal a new line of attack.