It is sometimes said that there are two, competing versions of W. V. O. Quine’s unrelenting empiricism, perhaps divided according to temporal periods of his career. According to one, logic is exempt from, or lies outside the scope of, the attack on the analytic-synthetic distinction. This logic-friendly Quine holds that logical truths and, presumably, logical inferences are analytic in the traditional sense. Logical truths are knowable a priori, and, importantly, they are incorrigible, and so immune from revision. The other, radical (...) reading of Quine does not exempt logic from the attack on analyticity and a priority. Logical truths and inferences are themselves part of the web of belief, and the same global methodology applies to logic as to any other part of the web, such as theoretical chemistry or ordinary beliefs about ordinary objects. Everything, including logic, is up for grabs in our struggle for holistic confirmation. The purpose of this paper is to examine the law of non-contradiction, and the concomitant principle of ex falso quodlibet, from the perspective of the principles advocated by the radical Quine. I show that he has no compelling reason to accept either of these. To put it bluntly, neither the law of non-contradiction nor the rule of ex falso quodlibet is empirically confirmed, and these principles fare poorly on the various criteria for theory acceptance on the methodology of the radical Quine. So the radical Quine is led rather quickly and rather directly into something in the neighborhood of Graham Priest’s dialetheism. (shrink)

One version of Moore’s Paradox is the challenge to account for the absurdity of beliefs purportedly expressed by someone who asserts sentences of the form ‘p & I do not believe that p’. The absurdity of these beliefs is philosophically puzzling, given that Moorean sentences are contingent and often true; and express contents that are unproblematic when presented in the third-person. In this paper I critically examine the most popular proposed solution to these two puzzles, according to which Moorean beliefs (...) are absurd because Moorean sentences are instances of pragmatic paradox; that is to say, the propositions they express are necessarily false-when-believed. My conclusion is that while a Moorean belief is a pragmatic paradox, it is not just another pragmatic paradox, because this diagnosis does not explain all the puzzling features of Moorean beliefs. In particularly, while this analysis is plausible in relation to the puzzle posed by characteristic of Moorean sentences, I argue that it fails to account for. I do so in the course of an attempt to formulate the definition of a pragmatic paradox in more precise formal terms, in order to see whether the definition is satisfied by Moorean sentences, but not by their third-person transpositions. For only an account which can do so could address adequately. After rejecting a number of attempted formalizations, I arrive at a definition which delivers the right results. The problem with this definition, however, is that it has to be couched in first-person terms, making an essential use of ‘I’. Thus the problem of accounting for first-/third-person asymmetry recurs at a higher order, which shows that the Pragmatic Paradox Resolution fails to identify the source of such asymmetry highlighted by Moore’s Paradox. (shrink)

'Epistemic' theories of vagueness notoriously claim that (despite the appearances to the contrary) all of our vague terms have sharp boundaries, it's just that we can't know what they are. Epistemic theories are typically criticized for failing to explain (1) the source of the ignorance postulated, and (2) how our terms could come to have such precise boundaries. Both of these objections will, however, be shown to rest on certain 'presentist' assumptions about the relation between use and meaning, and if (...) allows that the meaning constitutive elements of our linguistic practices can extend into the future, the possibility of a new sort of 'normative epistemicism' emerges. (shrink)

Temporal externalists argue that ascriptions of thought and utterance content can legitimately reflect contingent conceptual developments that are only settled after the time of utterance. While the view has been criticized for failing to accord with our “ordinary linguistic practices”, such criticisms (1) conflate our ordinary ascriptional practices with our more general beliefs about meaning, and (2) fail to distinguish epistemically from pragmatically motivated linguistic changes. Temporal externalism relates only to the former sort of changes, and the future usage relevant (...) to what we mean reflects reason-driven practices that are rational for us to defer to. (shrink)

In this paper I present two arguments against the thesis that we experience qualia. I argue that if we experienced qualia then these qualia would have to be essentially vague entities. And I then offer two arguments, one a reworking of Gareth Evans' argument against the possibility of vague objects, the other a reworking of the Sorites argument, to show that no such essentially vague entities can exist. I consider various objections but argue that ultimately they all fail. In particular (...) I claim that the stock responses to the Sorites argument fail against my reworking of the argument because they require us to make a distinction between a determinate reality and how that reality appears to us, whereas in the case of qualia we can make no such distinction. I conclude that there can be no such things as qualia. (shrink)

The presentation of the “dual picture of vagueness” in my earlier work is supplemented here with a number of additional considerations. I emphasize how the picture lends itself naturally to treatments of the contribution of a typical degree adjective to propositional content and to truth conditions. A number of reasonable refinements of the picture are presented, especially concerning occasions of use of a degree adjective in which a class containing a sorites series is somehow involved in content fixing, but in (...) such a way that an extension ultimately gets fixed for the predicate. I also develop the observation that standard theories of the logical and semantic paradoxes rely on the idea that the content-fixing mechanisms for the paradoxical expressions work well in general but fail in some localized cases, and that while standard theories of the sorites paradox are clearly not based on this idea at all, the dual theory is fully based on the idea. Next, I offer a few remarks on some recent theories of vagueness and the sorites that are broadly in the spirit of the dual picture, emphasizing the aspects where the latter compares favorably against those recent theories. Finally, the question whether the dual theory is statable with truth according to the theory itself is considered in more detail than in my earlier presentation. (shrink)

This book, provides a critical approach to all major logical paradoxes: from ancient to contemporary ones. There are four key aims of the book: 1. Providing systematic and historical survey of different approaches – solutions of the most prominent paradoxes discussed in the logical and philosophical literature. 2. Introducing original solutions of major paradoxes like: Liar paradox, Protagoras paradox, an unexpected examination paradox, stone paradox, crocodile, Newcomb paradox. 3. Explaining the far-reaching significance of paradoxes of vagueness and change for philosophy (...) and ontology. 4. Proposing a novel, well justified and, as it seems, natural classification of paradoxes. (shrink)

– We offer a new motivation for imprecise probabilities. We argue that there are propositions to which precise probability cannot be assigned, but to which imprecise probability can be assigned. In such cases the alternative to imprecise probability is not precise probability, but no probability at all. And an imprecise probability is substantially better than no probability at all. Our argument is based on the mathematical phenomenon of non-measurable sets. Non-measurable propositions cannot receive precise probabilities, but there is a natural (...) way for them to receive imprecise probabilities. The mathematics of non-measurable sets is arcane, but its epistemological import is far-reaching; even apparently mundane propositions are liable to be affected by non-measurability. The phenomenon of non-measurability dramatically reshapes the dialectic between critics and proponents of imprecise credence. Non-measurability offers natural rejoinders to prominent critics of imprecise credence. Non-measurability even reverses some of the critics’ arguments—by the very lights that have been used to argue against imprecise credences, imprecise credences are better than precise credences. (shrink)

I argue that the possibility of posthumous harm ought to be rejected. My argument centers on a kind of repugnancy case involving posthumous harm. Supposing the existence of posthumous harm, a person whose wellbeing was extremely high while she was alive could incur small posthumous harms over a long enough period such that it is true of that person that she had a life not worth living. I respond to various objections and in the end conclude that rejecting posthumous harm (...) is preferable to all other options. (shrink)

De um modo geral, queríamos mostrar que a filosofia tem suas próprias áreas, mas tem também subáreas em interdisciplinaridade com as ciências. As ciências e as disciplinas acadêmicas em geral têm problemas, cuja a solução pode ser encontrada empiricamente, por meio de experimentos, entrevistas, documentos, ou formalmente, por meio de cálculos etc, porém os problemas das filosofias dessas disciplinas são justamente os problemas mais fundamentais dessas disciplinas, que fundam o quadro conceitual e de pesquisa das mesmas, e que só poderiam (...) ser respondidos por meio de uma extensa argumentação. A filosofia de cada uma dessas disciplinas é uma mistura (a) de metafísica da disciplina, perguntando-se qual a natureza e justificação das entidades que formam o quadro teórico da disciplina, i.e., quais delas realmente existem na realidade (não sendo meros instrumentos para obter resultados) e quais as suas categorizações fundamentais, naturezas e funções teóricas, (b) de epistemologia dessa disciplina, ao nos perguntarmos sobre como tal área poderia obter conhecimento de modo confiável e se ela de fato o faz, e (c) de teorias do valor, ao nos perguntarmos, por exemplo, sobre qual o valor moral do desenvolvimento de uma certa disciplina e, finalmente, (d) a lógica, que perpassa tudo, ao nos perguntarmos sobre a consistência das teses assumidas pela disciplina. Não é à toa que falamos que a filosofia é mãe de todas as ciências. Ela é mãe tanto num sentido geracional, pois a maioria das ciências foram desenvolvimentos particulares, empíricos ou de cálculo, das questões filosóficas sobre um certo tema, quanto num sentido fundamental, pois é a filosofia que fornece os fundamentos mais gerais, metafísicos, epistêmicos, valorativos e lógicos, na construção do quadro teórico de cada ciência e na qualidade dos métodos para se aproximar da verdade que a disciplina utiliza. A biologia, por exemplo, foi criada por Aristóteles, tal como os primeiros desenvolvimentos da meteorologia (na verdade, esta começa com os pré-socráticos), e grande parte do fundamento da física atual jaz nas discussões de filosofia da física. Sendo você filósofo ou cientista de outra área, a filosofia promete te dar as bases para uma reflexão geral ou sobre sua área, que seja muito mais informada e profunda do que aquilo que você poderia realizar sem ela. /// In general, we wanted to show that philosophy has its own areas, but it also has subareas in interdisciplinarity with the sciences. The sciences and academic disciplines in general have problems, the solution of which can be found empirically, through experiments, interviews, documents, or formally, through calculations etc., but the problems of the philosophies of these disciplines are precisely the most fundamental problems. of these disciplines, which build their conceptual and research framework, and which could only be answered through extensive argumentation. The philosophy of each of these disciplines is a mixture (a) of metaphysics of the discipline, asking what is the nature and justification of the entities that form the theoretical framework of the discipline, ie, which ones really exist in reality (not being mere instruments for achieving results) and what are its fundamental categorizations, natures and theoretical functions, (b) the epistemology of this discipline, when we ask ourselves how such an area could obtain knowledge reliably and if it does, and (c) theories of value, when we ask ourselves, for example, about the moral value of the development of a certain discipline and, finally, (d) the logic, which permeates everything, when we ask ourselves about the consistency of the theses assumed by the discipline. It is not for nothing that we say that philosophy is the mother of all sciences. It is a mother both in a generational sense, as most sciences were particular empirical or formal developments of philosophical questions on a certain topic, and in a fundamental sense, as it is philosophy that provides the most general, metaphysical, epistemic, evaluative and logical foundations, in the construction of the theoretical framework of each science and in the quality of the methods to approach the truth that the discipline uses. Biology, for example, was created by Aristotle, like the first developments in meteorology (in fact, it starts with the pre-Socratics), and much of the foundation of current physics lies in discussions of the philosophy of physics. Whether you are a philosopher or scientist from another area, philosophy promises to give you the basis for a general reflection or about your area, which is much more informed and profound than what you could accomplish without it. (shrink)

ABSTRACTIn a recent paper, Alexander Greenberg defends a truth norm of belief according to which if one has some doxastic attitude towards p, one ought to believe that p if and only if p is true. He responds, in particular, to the ‘blindspot’ objection to truth norms such as da: in the face of true blindspots, such as it is raining and nobody believes that it is raining, truth norms such as da are unsatisfiable; they entail that one ought to (...) believe p, but if one does believe p, they entail that it is not the case that one ought to believe p. In this paper, it is argued that Greenberg’s response to the blindspot objection is unsatisfactory. (shrink)

Moore’s paradox, the infamous felt bizarreness of sincerely uttering something of the form “I believe grass is green, but it ain’t”—has attracted a lot of attention since its original discovery (Moore 1942). It is often taken to be a paradox of belief—in the sense that the locus of the inconsistency is the beliefs of someone who so sincerely utters. This claim has been labeled as the priority thesis: If you have an explanation of why a putative content could not be (...) coherently believed, you thereby have an explanation of why it cannot be coherently asserted. (Shoemaker 1995). The priority thesis, however, is insufficient to give a general explanation of Moore-paradoxical phenomena and, moreover, it’s false. I demonstrate this, then show how to give a commitment-theoretic account of Moore Paradoxicality, drawing on work by Bach and Harnish. The resulting account has the virtue of explaining not only cases of pragmatic incoherence involving assertions, but also cases of cognate incoherence arising for other speech acts, such as promising, guaranteeing, ordering, and the like. (shrink)

ABSTRACT Timothy Williamson offers the ordinary practice, the lottery and the Moorean argument for the ‘knowledge account’ that assertion is the only speech-act that is governed by the single rule that one must know its content. I show that these fail to support it and that the emptiness of the knowledge account renders mysterious why breaking the knowledge rule should be a source of criticism. I argue that focussing exclusively on the sincerity of the speech-act of letting one know engenders (...) a category mistake about the nature of constraints on assertion. After giving an analysis of assertion I propose that the norm of a type of assertion is the epistemic state one needs for one’s speech-act to succeed in being an assertion of that type and that the epistemic state in question is determined by the point of the type of assertion. One is practically irrational in violating the norm. (shrink)

The notion of an ideal reasoner has several uses in epistemology. Often, ideal reasoners are used as a parameter of (maximum) rationality for finite reasoners (e.g. humans). However, the notion of an ideal reasoner is normally construed in such a high degree of idealization (e.g. infinite/unbounded memory) that this use is unadvised. In this dissertation, I investigate the conditions under which an ideal reasoner may be used as a parameter of rationality for finite reasoners. In addition, I present and justify (...) the research program of computational epistemology, which investigates the parameter of maximum rationality for finite reasoners using computer simulations. (shrink)

This is a critical discussion of the accuracy-first approach to epistemic norms. If you think of accuracy (gradational or categorical) as the fundamental epistemic good and think of epistemic goods as things that call for promotion, you might think that we should use broadly consequentialist reasoning to determine which norms govern partial and full belief. After presenting consequentialist arguments for probabilism and the normative Lockean view, I shall argue that the consequentialist framework isn't nearly as promising as it might first (...) appear. (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)

The Paradox of the Surprise Examination has been a testing ground for a variety of frameworks in formal epistemology, from epistemic logic to probability theory to game theory and more. In this paper, I treat a related paradox, the Paradox of the Undiscoverable Position, as a test case for the possible-worlds style representation of epistemic states. I argue that the paradox can be solved in this framework, further illustrating the power of possible-worlds style modeling. The solution also illustrates an important (...) distinction between anti-performatory and unassimilable announcements of information. (shrink)

Review of Horgan and Potrc (2008). I discuss both their linguistic and ontological theses.

The idea of higher-order vagueness is usually associated with conceptions of vagueness that focus on the existence of borderline cases. What sense can be made of it within a conception of vagueness that focuses on tolerance instead? A proposal is offered here. It involves understanding ‘definitely’ not as a sentence operator but as a predicate modifier, and more precisely as an intensifier, that is, an operator that shifts the predicate extension along a scale. This idea is combined with the author’s (...) earlier approach to the semantics of vague expressions, which builds on the idea of a central gap associated with a predicate. The central gap approach is generalized to handle arbitrarily many iterations of ‘definitely’. (shrink)

In what follows, I strive to present the elements of a philosophical doctrine, which can be defined as dialectical contextualism. I proceed first to define the elements of this doctrine: dualities and polar contraries, the principle of dialectical indifference and the one-sidedness bias. I emphasize then the special importance of this doctrine in one specific field of meta-philosophy: the methodology for solving philosophical paradoxes. Finally, I describe several applications of this methodology on the following paradoxes: Hempel's paradox, the surprise examination (...) paradox and the Doomsday Argument. (shrink)

In 1907 Borel published a remarkable essay on the paradox of the Heap (“Un paradoxe économique: le sophisme du tas de blé et les vérités statistiques”), in which Borel proposes what is likely the first statistical account of vagueness ever written, and where he discusses the practical implications of the sorites paradox, including in economics. Borel’s paper was integrated in his book Le Hasard, published 1914, but has gone mostly unnoticed since its publication. One of the originalities of Borel’s essay (...) is that it puts forward a model of vagueness as imprecision, making particular use of the Gaussian law of measurement errors to model categorization. The aim of our paper is to give a presentation of the historical context of Borel’s essay, to spell out the mathematical details of his model, and to provide a critical assessment of his theory. Three aspects of Borel’s account are particularly discussed: the first concerns the comparison between Borel’s statistical account and posterior degree-theoretic accounts of vagueness. The second concerns the anti-epistemicist flavor of Borel’s approach, whereby the idea of statistical fluctuation is used to undermine the notion of sharp boundary for vague predicates. The third concerns the problematic link between Borel’s model of vagueness as imprecision and the notion of semantic indeterminacy. An English translation of Borel’s original essay is appended to this paper (Erkenntnis, this issue). (shrink)

The thesis that mental content is normative is ambiguous and has many forms. This article deals only with the thesis that normativity is connected to our mental attitudes rather than with the content of the attitudes, and more specifically with the view that it is connected to belief. A number of writers have proposed various versions of a ‘norm of truth’ attached to belief. I examine various versions of this claim, and defend it against recent criticisms according to which this (...) norm lacks normative force, that it violates the principle that ‘ought implies can,’ and that it is viciously circular. I defend the view that we should distinguish the statement of the objective norm and the way it is regulated, and that this distinction can answer most of the criticisms of the norm of truth for belief. (shrink)

This unique anthology of new, contributed essays offers a range of perspectives on various aspects of ontic vagueness. It seeks to answer core questions pertaining to onticism, the view that vagueness exists in the world itself. The questions to be addressed include whether vague objects must have vague identity, and whether ontic vagueness has a distinctive logic, one that is not shared by semantic or epistemic vagueness. The essays in this volume explain the motivations behind onticism, such as the plausibility (...) of mereological vagueness and indeterminacy in quantum mechanics and they offer various arguments both for and against ontic vagueness; onticism is also compared with other, competing theories of vagueness such as semanticism, the view that vagueness exists only in our linguistic representation of the world. Gareth Evans’s influential paper of 1978, “Can There Be Vague Objects?” gave a simple but cogent argument against the coherence of ontic vagueness. Onticism was subsequently dismissed by many. However, in recent years, researchers have become aware of the logical gaps in Evans’s argument and this has triggered a new wave of interest in onticism. Onticism is now widely regarded as at least a coherent view. Reflecting this growing consensus, the present anthology for the first time puts together essays that are focused on onticism and its various facets and it fills in the lacuna in the literature on vagueness, a much-discussed subject in contemporary philosophy. (shrink)

We investigate, for several modal logics but concentrating on KT, KD45, S4 and S5, the set of formulas B for which ${\square B}$ is provably equivalent to ${\square A}$ for a selected formula A (such as p, a sentence letter). In the exceptional case in which a modal logic is closed under the (‘cancellation’) rule taking us from ${\square C \leftrightarrow \square D}$ to ${C \leftrightarrow D}$ , there is only one formula B, to within equivalence, in this inverse image, (...) as we shall call it, of ${\square A}$ (relative to the logic concerned); for logics for which the intended reading of “ ${\square}$ ” is epistemic or doxastic, failure to be closed under this rule indicates that from the proposition expressed by a knowledge- or belief-attribution, the propositional object of the attitude in question cannot be recovered: arguably, a somewhat disconcerting situation. More generally, the inverse image of ${\square A}$ may comprise a range of non-equivalent formulas, all those provably implied by one fixed formula and provably implying another—though we shall see that for several choices of logic and of the formula A, there is not even such an ‘interval characterization’ of the inverse image (of ${\square A}$ ) to be found. (shrink)

In the norms of assertion literature there has been continued focus on a wide range of odd-sounding assertions that have been collected under the umbrella of Moore’s Paradox. Our aim in these brief remarks is not to attempt to settle the question of what makes an utterance Moorean decisively, but rather to present some new data bearing on it, and to argue that this new data is best explained by a new account of Moorean absurdity.

This volume presents mathematical game theory as an interface between logic and philosophy.

The Surprise Exam Paradox continues to perplex and torment despite the many solutions that have been offered. This paper proposes to end the intrigue once and for all by refuting one of the central pillars of the Surprise Exam Paradox, the 'No Friday Argument,' which concludes that an exam given on the last day of the testing period cannot be a surprise. This refutation consists of three arguments, all of which are borrowed from the literature: the 'Unprojectible Announcement Argument,' the (...) 'Wright & Sudbury Argument,' and the 'Epistemic Blindspot Argument.' The reason that the Surprise Exam Paradox has persisted this long is not because any of these arguments is problematic. On the contrary, each of them is correct. The reason that it has persisted so long is because each argument is only part of the solution. The correct solution requires all three of them to be combined together. Once they are, we may see exactly why the No Friday Argument fails and therefore why we have a solution to the Surprise Exam Paradox that should stick. (shrink)

Ci imbattiamo in un confine ogni volta che pensiamo a un’entità demarcata rispetto a ciò che la circonda. C’è un confine (una superficie) che delimita l’interno di una sfera dal suo esterno; c’è un confine (una frontiera) che separa il Maryland dalla Pennsylvania. Talvolta la collocazione esatta di un confine non è chiara o è in qualche modo controversa (come quando si cerchi di tracciare i limiti del monte Everest, o il confine del nostro corpo). Talaltra il confine non corrisponde (...) a una discontinuità fisica o a una differenziazione qualitativa (come nel caso dei confini del Wyoming, o della demarcazione tra la metà superiore e la metà inferiore di una sfera omogenea). Ma, che sia netto o confuso, naturale o artificiale, sembra esservi per ogni oggetto un confine che lo separa dal resto del mondo. Anche gli eventi hanno confini, quantomeno confini temporali. Le nostre vite sono delimitate dalle nostre nascite e morti; una partita di calcio comincia alle quindici in punto e termina col fischio finale dell’arbitro alle sedici e quarantacinque. E a volte si dice che anche le entità astratte, come i concetti o gli insiemi, hanno dei propri confini. Se tutto questo parlare di confini abbia davvero un senso, e se rifletta la struttura del mondo o solo l’attività organizzatrice del nostro intelletto, è però oggetto di profonda controversia filosofica. (shrink)

This paper proposes a new framework to solve the surprise examination paradox. I survey preliminary the main contributions to the literature related to the paradox. I introduce then a distinction between a monist and a dichotomic analysis of the paradox. With the help of a matrix notation, I also present a dichotomy that leads to distinguish two basically and structurally different notions of surprise, which are respectively based on a conjoint and a disjoint structure. I describe then how Quine's solution (...) and Hall's reduction apply to the version of the paradox corresponding to the conjoint structure. Lastly, I expose a solution to the version of the paradox based on the disjoint structure. (shrink)

In ‘Towards a Solution to the Sorites Paradox’, Graham Priest gives us a new account of the sorites based on fuzzy logic. The novelty lies in the suggestion that truth-value assignments should themselves be treated as fuzzy objects, i.e., objects about which we can make fuzzy identity statements. I argue that Priest’s solution does not have the explanatory force that Priest advocates. That is, it does not explain why we find the existence of a cut-off point counter-intuitive. I also argue (...) that this sort of explanation calls for a general theory that goes beyond the special case of linguistic vagueness, for the phenomenon is at bottom not linguistic. (shrink)

It is generally agreed that vague predicates like ‘red’, ‘rich’, ‘tall’, and ‘bald’, have borderline cases of application. For instance, a cloth patch whose color lies midway between a definite red and a definite orange is a borderline case for ‘red’, and an American man five feet eleven inches in height is (arguably) a borderline case for ‘tall’. The proper analysis of borderline cases is a matter of dispute, but most theorists of vagueness agree at least in the thought that (...) borderline cases for vague predicate ‘ ’ are items whose satisfaction of ‘ ’ is in some sense unclear or problematic: it is unclear whether or not the patch is red, unclear whether or not the man is tall.1 For example, Lynda Burns cites a widespread view as holding that borderline cases “are not definitely within the positive or negative extension of the predicate. … Border- line cases are seen as falling within a gap between the cases of definite application of the predicate and cases of definite application of its negation” (1995, 30). Michael Tye writes that the “concept of a border- line case is the concept of a case that is neither definitely in nor defi- nitely out” (1994b, 18). (shrink)

On two standard views of vagueness, vagueness as to whether Harry is bald entails that nobody knows whether Harry is bald—either because vagueness is a type of missing truth, and so there is nothing to know, or because vagueness is a type of ignorance, and so even though there is a truth of the matter, nobody can know what that truth is. Vagueness as to whether Harry is bald does entail that nobody clearly knows that Harry is bald and that (...) nobody clearly knows that Harry is not bald. But it does not entail that nobody knows that Harry is bald or that nobody knows that Harry is not bald. Hence, the two standard views of vagueness are mistaken. (shrink)

In an information state where various agents have both factual knowledge and knowledge about each other, announcements can be made that change the state of information. Such informative announcements can have the curious property that they become false because they are announced. The most typical example of that is 'fact p is true and you don't know that', after which you know that p, which entails the negation of the announcement formula. The announcement of such a formula in a given (...) information state is called an unsuccessful update. A successful formula is a formula that always becomes common knowledge after being announced. Analysis of information systems and 'philosophical puzzles' reveals a growing number of dynamic phenomena that can be described or explained by unsuccessful updates. This increases our understanding of such philosophical problems. We also investigate the syntactic characterization of the successful formulas. (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)

I provide a method of measuring the inconsistency of a set of sentences from 1-consistency, corresponding to complete consistency, to 0-consistency, corresponding to the explicit presence of a contradiction. Using this notion to analyze the lottery paradox, one can see that the set of sentences capturing the paradox has a high degree of consistency (assuming, of course, a sufficiently large lottery). The measure of consistency, however, is not limited to paradoxes. I also provide results for general sets of sentences.

In §2-4, I survey three extant ways of making sense of indeterminate truth and find each of them wanting. All the later sections of the paper are concerned with showing that the most promising way of making sense of indeterminate truth is via either a theory of truthmaker gaps or via a theory of truthmaking gaps. The first intimations of a truthmaker–truthmaking gap theory of indeterminacy are to be found in Quine (1981). In §5, we see how Quine proposes to (...) solve Unger’s problem of the many via positing the possibility of groundless truth. In §6, I elaborate the truthmaker gap model of indeterminacy first sketched by Sorensen (2001, ch.11) and use it to give a reductive analysis of indeterminate truth. In §7, I briefly assess what kind of formal framework can best express the possibility of truthmaker gaps. In §8, I contrast what I dub ‘the ordinary conception of worldly indeterminacy’ with Williamson’s conception of worldly indeterminacy. In §9, I show how one can distinguish linguistic from worldly indeterminacy on a truthmaker gap conception. In §10, I briefly sketch the relationship between truthmaker gaps and ignorance. In §11, I assess whether a truthmaker gap conception of vagueness is really just a form of epistemicism. In §12, I propose that truthmaker gaps can yield a plausible model of (semantic) presupposition failure. In §13, in response to the worry that a truthmaker gap conception of indeterminacy is both parochial and controversial—since it commits us to an implausibly strong theory of truthmaking—I set forth a truthmaking gap conception of indeterminacy. In §14, I answer the worry that groundless truths, of whatever species, are just unacceptably queer. A key part of this answer is that a truthmaker–truthmaking gap model of indeterminacy turns out to be considerably less queer than any model of indeterminacy which gives up on Tarski’s T-schema for truth (and cognate schemas). (shrink)

For Moore, it is a paradox that although I would be absurd in asserting that (it is raining but I don.

That it can explain the phenomenon of transparency, namely the fact that if you resolve whether p, you have thereby resolved whether to believe that p, was originally put forward as a great virtue of normativist conceptions of belief. However, non-normativists have convincingly shown that the permissive version of the truth norm of belief, which is one of the most plausible and promising versions of it, cannot in fact accommodate this phenomenon. Alarmed by this situation, in this paper I re-assess (...) the transparency phenomenon and its relation to different versions of the truth norm of belief. I argue that, contrary to how it appears, it is not even clear that the most tenable injunctive versions of the truth norm explain this phenomenon. I then argue that the transparency phenomenon consists of two distinct aspects which should be, but have not been, distinguished. What I call the ‘question-shifting’ aspect is explained by the truth norm, irrespective of how it is formulated, while what I call the ‘answer-shifting’ aspect is explanatorily empty and does not require any explanation, be it normative or otherwise. Therefore, understood properly, explaining transparency does remain a strength of normativist accounts of belief, and has no implications for which particular formulation of the truth norm we may adopt. (shrink)

This is a paper about the nature of metaphysical laws and their relation to the phenomenon of vagueness. Metaphysical laws are introduced as analogous to natural laws, and metaphysical indeterminism is modeled on causal indeterminacy. This kind of indeterminacy is then put to work in developing a novel theory of vagueness and a solution to the sorites paradox.

G.E. Moore noticed the oddity of statements like: “It's raining, but I don't believe it.” This oddity is often seen as analogous to the oddity of believing akratically, or believing what one believes one should not believe, and has been appealed to in denying the possibility of akratic belief. I describe a Belief Akratic's Paradox, analogous to Moore's paradox and centered on sentences such as: “I believe it's raining, but I shouldn't believe it.” I then defend the possibility of akratic (...) belief against appeals to this analogy, arguing both that akratic belief does not require belief-akratic-paradoxical belief, and that the latter is importantly different from Moorean belief. I conclude by considering the implications of these arguments for an understanding of both Moorean and akratic belief. (shrink)

We examine the paradox of the surprise examination using dynamic epistemic logic. This logic contains means of expressing epistemic facts as well as the effects of learning new facts, and is therefore a natural framework for representing the puzzle. We discuss a number of different interpretations of the puzzle in this context, and show how the failure of principle of success, that states that sentences, when learned, remain to be true and come to be believed, plays a central role in (...) understanding the puzzle. (shrink)