This paper argues that, insofar as we doubt the bivalence of the Continuum Hypothesis or the truth of the Axiom of Choice, we should also doubt the consistency of third-order arithmetic, both the classical and intuitionistic versions. -/- Underlying this argument is the following philosophical view. Mathematical belief springs from certain intuitions, each of which can be either accepted or doubted in its entirety, but not half-accepted. Therefore, our beliefs about reality, bivalence, choice and consistency should all be aligned.

ABSTRACT John MacFarlane’s truth relativism makes use of two notions of propositional truth: a monadic assessment sensitive one taken to be our ordinary truth notion, and a non-monadic one that is meant to account for the assessment sensitivity of the former notion. Some authors contend that any theory introducing a technical non-monadic truth notion has to make sense of it by defining or characterizing it in terms of ordinary monadic truth. First, I give some reasons why the relativist should not (...) discard this approach to make sense of the notion of truth relative to a context of assessment. Second, I argue that an illuminating characterization of this notion must provide an answer to a dilemma Paul Boghossian poses to the relativist. Third, I single out the characterization that can answer this dilemma. Finally, I contend that the relativist still needs to show that this solution works for each case subject to a relativist treatment. (shrink)

This volume includes a target paper, taking up the challenge to revive, within a modern (formal) framework, a medieval solution to the Liar Paradox which did ...

This book concerns the foundations of epistemic modality and hyperintensionality and their applications to the philosophy of mathematics. I examine the nature of epistemic modality, when the modal operator is interpreted as concerning both apriority and conceivability, as well as states of knowledge and belief. The book demonstrates how epistemic modality and hyperintensionality relate to the computational theory of mind; metaphysical modality and hyperintensionality; the types of mathematical modality and hyperintensionality; to the epistemic status of large cardinal axioms, undecidable propositions, (...) and abstraction principles in the philosophy of mathematics; to the modal and hyperintensional profiles of the logic of rational intuition; and to the types of intention, when the latter is interpreted as a hyperintensional mental state. Chapter 2 argues for a novel type of expressivism based on the duality between the categories of coalgebras and algebras, and argues that the duality permits of the reconciliation between modal cognitivism and modal expressivism. I also develop a novel topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel dynamic epistemic two-dimensional hyperintensional semantics. Chapter 3 provides an abstraction principle for epistemic (hyper-)intensions. Chapter 4 advances a topic-sensitive two-dimensional truthmaker semantics, and provides three novel interpretations of the framework along with the epistemic and metasemantic. Chapter 5 applies the fixed points of the modal μ-calculus in order to account for the iteration of epistemic states in a single agent, by contrast to availing of modal axiom 4 (i.e. the KK principle). The fixed point operators in the modal μ-calculus are rendered hyperintensional, which yields the first hyperintensional construal of the modal μ-calculus in the literature and the first application of the calculus to the iteration of epistemic states in a single agent instead of the common knowledge of a group of agents. Chapter 6 advances a solution to the Julius Caesar problem based on Fine's `criterial' identity conditions which incorporate conditions on essentiality and grounding. Chapter 7 provides a ground-theoretic regimentation of the proposals in the metaphysics of consciousness and examines its bearing on the two-dimensional conceivability argument against physicalism. The topic-sensitive epistemic two-dimensional truthmaker semantics developed in chapters 2 and 4 are availed of in order for epistemic states to be a guide to metaphysical states in the hyperintensional setting. -/- Chapters 8-12 provide cases demonstrating how the two-dimensional hyperintensions of hyperintensional, i.e. topic-sensitive epistemic two-dimensional truthmaker, semantics, solve the access problem in the epistemology of mathematics. Chapter 8 examines the interaction between my hyperintensional semantics and the axioms of epistemic set theory, large cardinal axioms, the Epistemic Church-Turing Thesis, the modal axioms governing the modal profile of Ω-logic, Orey sentences such as the Generalized Continuum Hypothesis, and absolute decidability. These results yield inter alia the first hyperintensional Epistemic Church-Turing Thesis and hyperintensional epistemic set theories in the literature. Chapter 9 examines the modal and hyperintensional commitments of abstractionism, in particular necessitism, and epistemic hyperintensionality, epistemic utility theory, and the epistemology of abstraction. I countenance a hyperintensional semantics for novel epistemic abstractionist modalities. I suggest, too, that observational type theory can be applied to first-order abstraction principles in order to make first-order abstraction principles recursively enumerable, i.e. Turing machine computable, and that the truth of the first-order abstraction principle for hyperintensions is grounded in its being possibly recursively enumerable and the machine being physically implementable. Chapter 10 examines the philosophical significance of hyperintensional Ω-logic in set theory and discusses the hyperintensionality of metamathematics. Chapter 11 provides a modal logic for rational intuition and provides a hyperintensional semantics. Chapter 12 avails of modal coalgebras to interpret the defining properties of indefinite extensibility, and avails of hyperintensional epistemic two-dimensional semantics in order to account for the interaction between the interpretational and objective modalities and truthmakers thereof. This yields the first hyperintensional category theory in the literature. I invent a new mathematical trick in which first order structures are treated as categories, and Vopenka's principle can be satisfied because of the elementary embeddings between the categories and generate Vopenka cardinals while bypassing the category of Set in category theory. Chapter 13 examines modal responses to the alethic paradoxes. Chapter 14 examines, finally, the modal and hyperintensional semantics for the different types of intention and the relation of the latter to evidential decision theory. (shrink)

This book is an inquiry into the philosophical concern with truth as one joint subject in philosophy of language and metaphysics and presents a theory of truth, substantive perspectivism (SP). Emphasizing our basic pre-theoretic understanding of truth (i.e., what is captured by the axiomatic thesis of truth that the nature of truth consists in capturing the way things are), and in the deflationism vs. substantivism debate background, SP argues for the substantive nature of non-linguistic truth and its notion’s indispensable substantive (...) explanatory role, both of which are not only intrinsically beyond what the linguistic function of the truth predicate can tell but are fundamentally related to the raison d’être of the truth predicate. Taking a holistic approach, SP endeavors to do justice to various reasonable perspectives, which are somehow contained in many competing accounts of truth, through a coordinate system: SP interprets such perspectives as distinct but related perspective-elaboration principles that distinctively (regarding distinct dimensions of the truth concern and/or for the sake of distinct purposes) elaborate, but are also unified by, the truth axiom thesis. To look at the issue from a broader vision, the book also takes a cross-tradition approach exploring the relationship between Daoist thinking of truth and thinking about truth in analytic philosophy.This book will enhance our systematic understanding of the issue through its holistic approach, broaden our vision on the issue via its cross-tradition approach, and enrich the conceptual and explanatory resources in treating the issue. (shrink)

This chapter focuses on alternative logics. It discusses a hierarchy of logical reform. It presents case studies that illustrate particular aspects of the logical revisionism discussed in the chapter. The first case study is of intuitionistic logic. The second case study turns to quantum logic, a system proposed on empirical grounds as a resolution of the antinomies of quantum mechanics. The third case study is concerned with systems of relevance logic, which have been the subject of an especially detailed reform (...) program. Finally, the fourth case study is paraconsistent logic, perhaps the most controversial of serious proposals. (shrink)

We introduce a framework that can be used to model both mathematics and human reasoning about mathematics. This framework involves stochastic mathematical systems (SMSs), which are stochastic processes that generate pairs of questions and associated answers (with no explicit referents). We use the SMS framework to define normative conditions for mathematical reasoning, by defining a “calibration” relation between a pair of SMSs. The first SMS is the human reasoner, and the second is an “oracle” SMS that can be interpreted as (...) deciding whether the question–answer pairs of the reasoner SMS are valid. To ground thinking, we understand the answers to questions given by this oracle to be the answers that would be given by an SMS representing the entire mathematical community in the infinite long run of the process of asking and answering questions. We then introduce a slight extension of SMSs to allow us to model both the physical universe and human reasoning about the physical universe. We then define a slightly different calibration relation appropriate for the case of scientific reasoning. In this case the first SMS represents a human scientist predicting the outcome of future experiments, while the second SMS represents the physical universe in which the scientist is embedded, with the question–answer pairs of that SMS being specifications of the experiments that will occur and the outcome of those experiments, respectively. Next we derive conditions justifying two important patterns of inference in both mathematical and scientific reasoning: (i) the practice of increasing one’s degree of belief in a claim as one observes increasingly many lines of evidence for that claim, and (ii) abduction, the practice of inferring a claim’s probability of being correct from its explanatory power with respect to some other claim that is already taken to hold for independent reasons. (shrink)

According to some Philosophy for Children theorists, the pedagogy of the Community of Inquiry hinges upon the acceptance of a pragmatist epistemology. The underlying idea is that it is possible to participate, and to justify participation, in a community of inquiry only if some pragmatist view of truth and knowledge is true and accepted by the participants engaged in dialogue. In this article we argue that this claim is false. In this way, we want to free the pedagogy of the (...) Community of Inquiry from some epistemological assumptions that we regard as unwarranted. To support our contention, we shall highlight two distinctions that are important in order to appreciate the connection between epistemology and education: first, the distinction between the disposition of intellectual humility and the belief in fallibilism; second, the belief in the existence of Cartesian certainties and the attitude of psychological certainty. Finally, we also argue that to vindicate dialogic inquiry it is neither necessary to adopt a pragmatist theory of truth, nor is it necessary to regard warranted judgement as the primary aim of inquiry. In contrast, we argue that truth is the aim of inquiry, and so is the aim of children when they participate in a dialogic inquiry. In this way we also suggest a justification of philosophy with children that does not instrumentalize it. (shrink)

Mental files, in Recanati's framework, function as 'singular terms in the language of thought' ; they serve to think about objects in the world (and to store information about them). But they have a derived, metarepresentational function : they serve to represent how other subjects think about objects in the world. To account for the metarepresentational use of files, Recanati introduces the notion of an 'indexed file', i.e. a vicarious file that stands, in the subject's mind, for another subject's file (...) about an object. Using that notion, he argues, one can provide an analysis of attitude ascriptions and the conniving use of empty singular terms. (shrink)

This paper aims to provide a mathematically tractable background against which to model both modal cognitivism and modal expressivism. I argue that epistemic modal algebras, endowed with a hyperintensional, topic-sensitive epistemic two-dimensional truthmaker semantics, comprise a materially adequate fragment of the language of thought. I demonstrate, then, how modal expressivism can be regimented by modal coalgebraic automata, to which the above epistemic modal algebras are categorically dual. I examine five methods for modeling the dynamics of conceptual engineering for intensions and (...) hyperintensions. I develop a novel topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel dynamic epistemic two-dimensional hyperintensional semantics. I examine then the virtues unique to the modal expressivist approach here proffered in the setting of the foundations of mathematics, by contrast to competing approaches based upon both the inferentialist approach to concept-individuation and the codification of speech acts via intensional semantics. (shrink)

John MacFarlane explores how we might make sense of the idea that truth is relative. He provides new, satisfying accounts of parts of our thought and talk that have resisted traditional methods of analysis, including what we mean when we talk about what is tasty, what we know, what will happen, what might be the case, and what we ought to do.

Consider the following 'principles':2(Norm of Belief Schema) Necessarily, a belief of is correct (relative to some scenario) if and only if p (at that scenario) — where 'p' has the aforementioned content .(Generalized Norm of Belief) Necessarily, for all propositions , a belief of is correct (relative to some scenario) if and only if is true (at that scenario).Both 'principles' appear to capture the aim(s) of belief. (NBS) particularizes the aims to beliefs of distinct content-types. (GNB) generalizes these aims of (...) beliefs as truth. Properly understood, the instances of (NBS) appear to be at least approximately true as does (GNB). Of course, one might harbor concerns about whether these are mere .. (shrink)

Recent years have seen an explosion of interest in the semantics of knowledge-attributing sentences, not just among epistemologists but among philosophers of language seeking a general understanding of linguistic context sensitivity. Despite all this critical attention, however, we are as far from consensus as ever. If we have learned anything, it is that each of the standard views—invariantism, contextualism, and sensitive invariantism—has its Achilles’ heel: a residuum of facts about our use of knowledge attributions that it can explain only with (...) special pleading. This is not surprising if, as I will argue, there is a grain of truth in each of these views. (shrink)

The age-old question “What is truth?” is not an unambiguous one. There are at least two different meanings. In one sense, it is a semantic question about the meaning of the word “truth” and/or a metaphysical question about the nature of the property of truth, that is, how truth can be defined in terms of other notions, if it is definable at all. In another sense, it is an epistemological question about the criterion or test of truth, that is, how (...) we can recognize or accept (empirical) propositions as true. Ayer, in Language, Truth and Logic (LTL) and some other articles, tried to convince us that when we attempt to elucidate a theory of truth, we are only engaging in the epistemological project of finding the criterion of truth. This anti-semantical and anti-metaphysical view is based on Ayer’s (radical) deflationism about truth. In this chapter, I will argue that since Ayer did not accept that the criterion of truth is intimately related to the concept of truth, he can be seen as a deflationist about the nature of truth and as an advocate of a certain (Schlickian) kind of correspondence conception about the criterion of truth. His position would not be tenable if he had maintained what some of his contemporaries accepted, namely that there is a close connection between the two truth-theoretical tasks: the definitional and the criterial one. (shrink)

A. J. Ayer’s Language, Truth, and Logic had been responsible for introducing the Vienna Circle’s ideas, developed within a Germanophone framework, to an Anglophone readership. Inevitably, this migration from one context to another resulted in the alteration of some of the concepts being transmitted. Such alterations have served to facilitate a number of false impressions of Logical Empiricism from which recent scholarship still tries to recover. In this paper, I will attempt to point to the ways in which LTL has (...) helped to foster the various mistaken stereotypes about Logical Empiricism which were combined into the received view. I will begin by examining Ayer’s all too brief presentation of an Anglocentric lineage for his ideas. This lineage, as we shall see, simply omits the major 19th century Germanophone influences on the rise of analytic philosophy. The Germanophone ideas he presents are selectively introduced into an Anglophone context, and directed towards various concerns that arose within that context. I will focus on the differences between Carnap’s version of the overcoming of metaphysics, and Ayer’s reconfiguration into what he calls the elimination of metaphysics. Having discussed the above, I will very briefly outline the consequences that Ayer’s radicalisation of the Vienna Circle’s doctrines had on the subsequent Anglophone reception of Logical Empiricism. (shrink)

What is the relation between meaning and use? This chapter first defends a non-reductionist understanding of Wittgenstein’s suggestion that ‘the meaning of a word is its use in the language’; facts about meaning cannot be reduced to, or explained in terms of, facts about use, characterized non-semantically. Nonetheless, it is contended, facts about meaning do supervene on non-semantic facts about use. That supervenience thesis is suggested by comments of Wittgenstein’s and is consistent with his view of meaning and rule-following. Semantic (...) supervenience is then defended against two criticisms: first, John McDowell’s suggestion that the supervenience thesis falsifies the epistemology of meaning and fails to accommodate common-sense truths about meaning; second, a series of counter-examples proposed by Stephen Kearns and Ofra Magidor, who argue that worlds may differ semantically without differing non-semantically. It is argued that neither criticism is convincing: we should accept the thesis that semantic facts supervene on non-semantic facts. (shrink)

Surprisingly little has been written about hedged assertion. Linguists often focus on semantic or syntactic theorizing about, for example, grammatical evidentials or epistemic modals, but pay far less attention to what hedging does at the level of action. By contrast, philosophers have focused extensively on normative issues regarding what epistemic position is required for proper assertion, yet they have almost exclusively considered unqualified declaratives. This essay considers the linguistic and normative issues side-by-side. We aim to bring some order and clarity (...) to thinking about hedging, so as to illuminate aspects of interest to both linguists and philosophers. In particular, we consider three broad questions. 1) The structural question: when one hedges, what is the speaker’s commitment weakened from? 2) The functional question: what is the best way to understand how a hedge weakens? And 3) the taxonomic question: are hedged assertions genuine assertions, another speech act, or what? (shrink)

Some philosophers have argued that truth is a norm of judgement and have provided a variety of formulations of this general thesis. In this paper, I shall side with these philosophers and assume that truth is a norm of judgement. What I am primarily interested in here are two core questions concerning the judgement-truth norm: (i) what are the normative relationships between truth and judgement? And (ii) do these relationships vary or are they constant? I argue for a pluralist picture—what (...) I call Normative Alethic Pluralism (NAP)—according to which (i) there is more than one correct judgement-truth norm and (ii) the normative relationships between truth and judgement vary in relation to the subject matter of the judgement. By means of a comparative analysis of disagreement in three areas of the evaluative domain—refined aesthetics, basic taste and morality—I show that there is an important variability in the normative significance of disagreement—I call this the variability conjecture. By presenting a variation of Lynch’s scope problem for alethic monism, I argue that a monistic approach to the normative function of truth is unable to vindicate the conjecture. I then argue that normative alethic pluralism provides us with a promising model to account for it. (shrink)

The problem analysed in this paper is whether we can gain knowledge by using valid inferences, and how we can explain this process from a model-theoretic perspective. According to the paradox of inference (Cohen & Nagel 1936/1998, 173), it is logically impossible for an inference to be both valid and its conclusion to possess novelty with respect to the premises. I argue in this paper that valid inference has an epistemic significance, i.e., it can be used by an agent to (...) enlarge his knowledge, and this significance can be accounted in model-theoretic terms. I will argue first that the paradox is based on an equivocation, namely, it arises because logical containment, i.e., logical implication, is identified with epistemological containment, i.e., the knowledge of the premises entails the knowledge of the conclusion. Second, I will argue that a truth-conditional theory of meaning has the necessary resources to explain the epistemic significance of valid inferences. I will explain this epistemic significance starting from Carnap’s semantic theory of meaning and Tarski’s notion of satisfaction. In this way I will counter (Prawitz 2012b)’s claim that a truth-conditional theory of meaning is not able to account the legitimacy of valid inferences, i.e., their epistemic significance. (shrink)

Analogien lassen sich aus unserem vernünftigen Nachdenken und Argumentieren kaum wegdenken. Ganz zurecht stellen sie eines der klassischen Themen der Argumentationstheorie dar. Doch wie genau sollte die argumentative Rolle von Analogien in Argumentrekonstruktionen dargestellt werden? Das ist die Leitfrage dieses Beitrags. Zunächst wird mit Michael Dummetts Schach-Analogie ein prominentes Beispiel dargestellt und eine genauere Charakterisierung des Analogiebegriffs vorgeschlagen. Danach wird die gängigste Rekonstruktionsform von Analogien diskutiert, das Analogieargument, und in einigen Punkten verfeinert. Vor diesem Hintergrund schlägt der Beitrag eine zweite, (...) alternative Rekonstruktionsform vor, in der zwei analoge Argumente an die Stelle eines einzelnen Analogiearguments treten. Nachdem diese beiden Rekonstruktionsformen an einem weiteren berühmten Beispiel vorgeführt wurden, an Peter Singers Teich-Analogie, wird diskutiert, wie sich diese beiden Varianten gegenseitig ergänzen und welche Stärken und Schwächen sie haben. Es zeigt sich, dass Analogien nicht nur in Form von Analogieargumenten einen zentralen Topos eines Einzelarguments darstellen. Darüber hinaus kann die Untersuchung analoger Argumente bereits selbst als argumentationstheoretische Topik verstanden werden. (shrink)

The book presents a thoroughly elaborated logical theory of generalized truth-values understood as subsets of some established set of truth values. After elucidating the importance of the very notion of a truth value in logic and philosophy, we examine some possible ways of generalizing this notion. The useful four-valued logic of first-degree entailment by Nuel Belnap and the notion of a bilattice constitute the basis for further generalizations. By doing so we elaborate the idea of a multilattice, and most notably, (...) a trilattice of truth values – a specific algebraic structure with information ordering and two distinct logical orderings, one for truth and another for falsity. Each logical order not only induces its own logical vocabulary, but determines also its own entailment relation. We consider both semantic and syntactic ways of formalizing these relations and construct various logical calculi. (shrink)

The question how to turn the principles implicitly governing the concept of truth into an explicit definition of the concept hence coalesced with the question how to get a finite grip on the infinity of T-sentences. Tarski's famous and ingenious move was to introduce a new concept, satisfaction, which could be, on the one hand, recursively defined, and which, on the other hand, straightforwardly yielded an explication of truth. A surprising 'by-product' of Tarski's effort to bring truth under control was (...) the breathtaking finding that truth is in a precisely defined sense ineffable, that no non trivial language can contain a truth-predicate which would be adequate for the very 4 language. This implied that truth proved itself to be strangely 'language-dependent': we can have a concept of truth-in-L for any language L, but we cannot have a concept of truth applicable to every language. In a sense, this means, as Quine put it, that truth belongs to "transcendental metaphysics", and Tarski's 'scientific' investigations seem to lead us back towards a surprising proximity of some more traditional philosophical views on truth. 3. TARSKI'S THEORY AS A PARADIGM So far Tarski himself. Subsequent philosophers then had to find out what his considerations of the concept of truth really mean and what are their consequences; and this now seems to be an almost interminable task. (shrink)

This book brings together philosophers, mathematicians and logicians to penetrate important problems in the philosophy and foundations of mathematics. In philosophy, one has been concerned with the opposition between constructivism and classical mathematics and the different ontological and epistemological views that are reflected in this opposition. The dominant foundational framework for current mathematics is classical logic and set theory with the axiom of choice. This framework is, however, laden with philosophical difficulties. One important alternative foundational programme that is actively pursued (...) today is predicativistic constructivism based on Martin-Löf type theory. Associated philosophical foundations are meaning theories in the tradition of Wittgenstein, Dummett, Prawitz and Martin-Löf. What is the relation between proof-theoretical semantics in the tradition of Gentzen, Prawitz, and Martin-Löf and Wittgensteinian or other accounts of meaning-as-use? What can proof-theoretical analyses tell us about the scope and limits of constructive and predicative mathematics? (shrink)

This anthology of the very latest research on truth features the work of recognized luminaries in the field, put together following a rigorous refereeing process. Along with an introduction outlining the central issues in the field, it provides a unique and unrivaled view of contemporary work on the nature of truth, with papers selected from key conferences in 2011 such as Truth Be Told, Truth at Work, Paradoxes of Truth and Denotation and Axiomatic Theories of Truth. Studying the nature of (...) the concept of ‘truth’ has always been a core role of philosophy, but recent years have been a boom time in the topic. With a wealth of recent conferences examining the subject from various angles, this collection of essays recognizes the pressing need for a volume that brings scholars up to date on the arguments. Offering academics and graduate students alike a much-needed repository of today’s cutting-edge work in this vital topic of philosophy, the volume is required reading for anyone needing to keep abreast of developments, and is certain to act as a catalyst for further innovation and research. (shrink)

La teleosemántica es una teoría teleológica de las representaciones mentales, propugnada por David Papineau, que tiene como propósito ofrecer una explicación naturalista y evolucionista de dichas representaciones, en particular de las creencias. Mi objetivo será analizar las creencias y su relación con la verdad en la obra de Papineau. Según Papineau, los contenidos y las representaciones mentales, específicamente las creencias, cumplen funciones derivadas de la evolución biológica de la especie, y correlativamente, la finalidad de las creencias y los contenidos proviene (...) de las funciones biológicas que cada una de ellas tiene. De acuerdo a Papineau, para que las creencias cumplan sus funciones biológicas deben ser verdaderas, es decir, corresponder con la realidad. Defenderé la idea de que, a diferencia de lo que plantea la teleosemántica, la verdad y la falsedad, o más específicamente, los enunciados verdaderos y falsos son doxásticos, es decir, son enunciados que expresan creencias. Las creencias no tienen que ser verdaderas, sino más bien útiles, de manera que el que sean verdaderas o no es un producto secundario de la creencia. (shrink)

Provisional draft, pre-production copy of my book “The Modal Future” (forthcoming with Cambridge University Press).

This dissertation concerns the foundations of epistemic modality. I examine the nature of epistemic modality, when the modal operator is interpreted as concerning both apriority and conceivability, as well as states of knowledge and belief. The dissertation demonstrates how phenomenal consciousness and gradational possible-worlds models in Bayesian perceptual psychology relate to epistemic modal space. The dissertation demonstrates, then, how epistemic modality relates to the computational theory of mind; metaphysical modality; deontic modality; logical modality; the types of mathematical modality; to the (...) epistemic status of undecidable propositions and abstraction principles in the philosophy of mathematics; to the apriori-aposteriori distinction; to the modal profile of rational propositional intuition; and to the types of intention, when the latter is interpreted as a modal mental state. Examining the nature of epistemic logic itself, I develop a novel approach to conditions of self-knowledge in the setting of the modal μ-calculus, as well as novel epistemicist solutions to Curry's, the liar, and the knowability paradoxes. Solutions to previously intransigent issues concerning the first-person concept; the distinction between fundamental and derivative truths; and the unity of intention and its role in decision theory, are developed along the way. (shrink)

What is the difference between belief and desire? In order to explain the difference, recent philosophers have appealed to the metaphor of.

I consider the problem of reflective knowledge faced by views that treat sensitivity as a sufficient condition for knowledge, or as a major ingredient of the concept, as in the analysis I advance in Scepticism and Reliable Belief. I present the problem as concerning the correct analysis of SATs — beliefs to the effect that one of my current beliefs is true. I suggest that a plausible analysis of SATs should treat them as neither true nor false when they ascribe (...) truth to a non-existent belief. I argue that the problem is inescapable if we construe SATs as ascribing the property of truth to a belief. Deflationism manages to avoid the problem of reflective knowledge, but it does so by violating alethic priority — the principle that our account of representation must be built on our account of truth. I argue that we can avoid the problem of reflective knowledge while preserving alethic priority with a pragmatist account of truth — according to which truth is explicated in terms of the rules that govern the practice of assessing judgments and related items as true or false. (shrink)

Every student of English-speaking analytical metaphysics is taught that the early twentieth century philosophical debate about truth confronted the correspondence theory, supported by Russell, Moore, the early Wittgenstein and, later, J.L. Austin, with the coherence theory advocated by the British Idealists. Sometimes the pragmatist conception of truth deriving from Dewey, William James, and C.S. Peirce is regarded as a third player. And as befits a debate at the dawn of analytical philosophy, the matter in dispute is normally taken to have (...) been the proper analysis of the concept.No doubt this conception nicely explains some of the characteristic turns taken in the debate. Analysis, as traditionally conceived, has to consist in the provision of illuminating conceptual equivalences; and illumination will depend, according to the standard rules of play, on the analysans’ utilizing only concepts which, in the best case, are in some way prior to and independent of the notion being analyzed — or, if that's too much to ask, then concepts which at least permit of some form of explication which does not in turn take one straight back to that notion. (shrink)

Revisionary theories of logic or truth require revisionary theories of mind. This essay outlines nonclassically based theories of rational belief, desire, and decision making, singling out the supervaluational family for special attention. To see these nonclassical theories of mind in action, this essay examines a debate between David Lewis and Derek Parfit over what matters in survival. Lewis argued that indeterminacy in personal identity allows caring about psychological connectedness and caring about personal identity to amount to the same thing. The (...) essay argues that Lewis's treatment of two of Parfit's puzzle cases—degreed survival and fission—presuppose different nonclassical treatments of belief and desire. (shrink)

Writers such as Stalnaker and Dummett have argued that specific features of subjunctive conditional statements undermine the principle of bivalence. This, paper is concerned with rebutting such claims. 1. It is shown how subjective conditionals pose a prima facie threat to bivalence, and how this threat can be dissolved by a distinction between the results of negating a subjective conditional and of negating its consequent. To make this distinction is to side with Lewis against Stalnaker in a dispute about possible (...) worlds semantics for such conditionals, and reasons are given for doing so. 2. These arguments are extended to answer Dummett''s claim that behaviourist and phenomenalist analyses in terms of subjunctive conditions violate bivalence. This answer is shown to be compatible with the principle that hypothetical statements are true only in virtue of categorical facts. (shrink)

The view that truth is the norm of assertion has fallen out of fashion. The recent trend has been to think that knowledge is the norm of assertion. Objections to the knowledge view proceed almost exclusively by appeal to alleged counterexamples. While it no doubt has a role to play, such a strategy relies on intuitions concerning hypothetical cases, intuitions which might not be shared and which might shift depending on how the relevant cases are fleshed out. In this paper, (...) I reject the knowledge view on principled grounds. More specifically, by appeal to a principle which is motivated independently of the debate over the norms of assertion and which is already accepted by many proponents of the knowledge view, I show the knowledge view to be false while simultaneously accounting for why it might seem to be true. In doing so, I provide a novel defence of the unfashionable truth view. (shrink)

Belief is said to be essentially subject to a norm of truth. This view has been challenged on the ground that the truth norm cannot provide guidance on an intuitive inferentialist model of guidance and thus cannot be genuinely normative. One response to the No Guidance argument is to show how the truth norm can guide belief-formation on the inferentialist model of guidance. In this paper, I argue that this response is inadequate in light of emerging empirical evidence about our (...) system of belief-formation. I will then motivate an alternative response and present, in rough outline, a viable, reason-responsive model of epistemic guidance on which the truth norm can guide. (shrink)

What the world needs now is another theory of vagueness. Not because the old theories are useless. Quite the contrary, the old theories provide many of the materials we need to construct the truest theory of vagueness ever seen. The theory shall be similar in motivation to supervaluationism, but more akin to many-valued theories in conceptualisation. What I take from the many-valued theories is the idea that some sentences can be truer than others. But I say very different things to (...) the ordering over sentences this relation generates. I say it is not a linear ordering, so it cannot be represented by the real numbers. I also argue that since there is higher-order vagueness, any mapping between sentences and mathematical objects is bound to be inappropriate. This is no cause for regret; we can say all we want to say by using the comparative truer than without mapping it onto some mathematical objects. From supervaluationism I take the idea that we can keep classical logic without keeping the familiar bivalent semantics for classical logic. But my preservation of classical logic is more comprehensive than is normally permitted by supervaluationism, for I preserve classical inference rules as well as classical sequents. And I do this without relying on the concept of acceptable precisifications as an unexplained explainer. The world does not need another guide to varieties of theories of vagueness, especially since Timothy Williamson (1994) and Rosanna Keefe (2000) have already provided quite good guides. I assume throughout familiarity with popular theories of vagueness. (shrink)

Imperatives cannot be true or false, so they are shunned by logicians. And yet imperatives can be combined by logical connectives: "kiss me and hug me" is the conjunction of "kiss me" with "hug me". This example may suggest that declarative and imperative logic are isomorphic: just as the conjunction of two declaratives is true exactly if both conjuncts are true, the conjunction of two imperatives is satisfied exactly if both conjuncts are satisfied—what more is there to say? Much more, (...) I argue. "If you love me, kiss me", a conditional imperative, mixes a declarative antecedent ("you love me") with an imperative consequent ("kiss me"); it is satisfied if you love and kiss me, violated if you love but don't kiss me, and avoided if you don't love me. So we need a logic of three -valued imperatives which mixes declaratives with imperatives. I develop such a logic. (shrink)

We argue that thinking of the man-machine comparison in terms of a contest involves, in a reasonable scenario, a criterion of success that is neutral. This is because we want to avoid a petitio principii. We submit, however, that, by looking at things this way, one makes the most essential human things invisible. Thus, in a sense, the contest approach is self-defeating.

Abstract I argue against the two most influential readings of Frege's methodology in the philosophy of logic. Dummett's ?semanticist? reading sees Frege as taking notions associated with semantical content?and in particular, the semantical notion of truth?as primitive and as intelligible independently of their connection to the activity of judgment, inference, and assertion. Against this, the ?pragmaticist? reading proposed by Brandom and Ricketts sees Frege as beginning instead from the independent and intuitive grasp that we allegedly have on the latter activity (...) and only then moving on to explain semantical notions in terms of the nature of such acts. Against both readings, I argue, first, that Frege gives clear indication that he takes semantical and pragmatical notions to be equally primitive, such that he would reject the idea that either sort of notion could function as the base for a non-circular explanation of the other. I argue, secondly, that Frege's own method for conveying the significance of these primitive notions?an activity that Frege calls ?elucidation??is, in fact, explicitly circular in nature. Because of this, I conclude that Frege should be read instead as conceiving of our grasp of the semantical and pragmatical dimensions of logic as far more of a holistic enterprise than either reading suggests. (shrink)

According to truth pluralism, sentences from different areas of discourse can be true in different ways. This view has been challenged to make sense of logical validity, understood as necessary truth preservation, when inferences involving different areas are considered. To solve this problem, a natural temptation is that of replicating the standard practice in many-valued logic by appealing to the notion of designated values. Such a simple approach, however, is usually considered a non-starter for strong versions of truth pluralism, since (...) designation seems to embody nothing but a notion of generic truth. In this paper, I explore the analogy with many-valued logic by comparing the problem of mixed inferences with Suszko’s thesis, and argue that the strong pluralist has room to resist the commitment to a generic property of truth by undermining the semantic significance of Suszko’s reduction. (shrink)

The macaque washes a potato in a stream. It does this because it has seen the dirt come off as another macaque washed its potato, and it knows that clean potato.

International Journal of Philosophical Studies 0967-2559 (print)/1466-4542 (online) Original Article.

I argue for an account of semantic paradox that requires minimal logical revision. I first consider a phenomenon that is common to the paradoxes of definability, Russell’s paradox and the Liar. The phenomenon—which I call Repetition—is this: given a paradoxical expression, we can go on to produce a semantically unproblematic expression composed of the very same words. I argue that Kripke’s and Field’s theories of truth make heavy weather of Repetition, and suggest a simpler contextual account. I go on to (...) outline a ‘singularity’ theory of semantical predicates in the spirit of remarks of Gödel. According to this theory, ‘denotes’, ‘extension’ and ‘true’ are context-sensitive expression that apply almost everywhere on a given occasion of use, except for certain singular points. I then turn to revenge paradoxes, and argue that even the dialetheist is subject to revenge. I then examine how the singularity theory responds to revenge. (shrink)

The central premise of Michael Dummett's global argument for anti-realism is the thesis that a speaker's grasp of the meaning of a declarative, indexical-free sentence must be manifested in her uses of that sentence. This enigmatic thesis has been the subject of a great deal of discussion, and something of a consensus has emerged about its content and justification. The received view is that the manifestation thesis expresses a behaviorist and reductive theory of meaning, essentially in agreement with Quine's view (...) of language, and motivated by worries about the epistemology of communication. In the present paper I begin by arguing that this standard interpretation of the manifestation thesis is neither particularly faithful to Dummett's writings nor philosophically compelling. I then continue by reconstructing, from Dummett's texts, an account of the manifestation thesis, and of its justification, that differ sharply from the received view. On my reading, the thesis is motivated not epistemologically, but conceptually. I argue that connections among our conceptions of meaning, assertion, and justification lead to a conclusion about the metaphysics of meaning: we cannot form a clearly coherent conception of how two speakers can attach different meanings to a sentence without at the same time differing in what they count as justifying assertions made with that sentence. I conclude with some suggestions about how Dummett's argument for global anti-realism should be understood, given my account of the manifestation thesis. (shrink)

The paper seeks to answer two new questions about truth and scientific change: What lessons does the phenomenon of scientific change teach us about the nature of truth? What light do recent developments in the theory of truth, incorporating these lessons, throw on problems arising from the prevalence of scientific change, specifically, the problem of pessimistic meta-induction?

In Category Mistakes, Ofra Magidor provides two arguments against the view that category mistakes express propositions that are not truth-evaluable at some world. I argue that her first, Williamsonian argument against this view begs the question, and that her second argument rests on a misleading conception of how semantic defect results in infelicity judgments. I conclude by conceding that she is still correct to stress that the view she opposes face noteworthy foundational and empirical challenges.