I defend the non-cognitivist outlook on knowledge of grammar from the criticisms levelled against it by Jonathan Knowles. The first part of the paper is largely critical. First, I argue that Knowles's argument against Christopher Peacocke and Martin Davies's non-cognitivist account of the psychological reality of grammar fails, and thus that no reason has been given to think that cognitivism is integral to an understanding of Chomskyan theoretical linguistics. Second, I argue that cognitivism is philosophically problematic. In particular, I argue (...) (a) that Knowles misunderstands Stephen Stich and Gareth Evans's points about inferential integration; and (b) that Knowles misunderstands the philosophical status and demands of Evans's Generality Constraint. In the final, non-critical part of the paper, I try to show that the Stich and Evans's constraints, together with a Self-Knowledge Constraint, are genuine constitutive constraints by showing how they have rationality as their underlying organizing principle. I argue further that recognizing the constitutive character of these constraints allows one to distinguish two kinds of psychological explanation; in this sense, the constraints mark a genuine boundary in our theorizing about the mind. (shrink)

According to Wrights minimalism, a notion of truth neutral with respect to realism and antirealism can be built out of the notion of warranted assertibility and a set of a priori platitudes among which the Equivalence Schema has a prominent role. Wright believes that the debate about realism and antirealism will be properly and fruitfully developed if both parties accept the conceptual framework of minimalism. In this paper, I show that this conceptual framework commits the minimalist to the realist thesis (...) that there are mind-independent propositions; with the consequence that minimalism is not neutral to realism and antirealism. I suggest that Wright could avert this conclusion if he rejected the customary interpretation of the Equivalence Schema according to which this Schema applies to propositions. This would however render minimalism unpalatable to philosophers who welcome the traditional reading of the Equivalence Schema and believe that propositions are bearers of truth. (shrink)

The central claim is that the semantic knowledge exercised by people when they speak is practical knowledge. The relevant idea of practical knowledge is explicated, applied to the case of speaking, and connected with an idea of agents’ knowledge. Some defence of the claim is provided.

I have argued that without an adequate solution to the knower paradox Fitch's Proof is- or at least ought to be-ineffective against verificationism. Of course, in order to follow my suggestion verificationists must maintain that there is currently no adequate solution to the knower paradox, and that the paradox continues to provide prima facie evidence of inconsistent knowledge. By my lights, any glimpse at the literature on paradoxes offers strong support for the first thesis, and any honest, non-dogmatic reflection on (...) the knower paradox provides strong support for the second. Whether verificationists want to go the route I've suggested is not for me todecide. As in the previous section my aim has been that of defending the mere viability of verificationism in the face of what many, many philosophers have taken to be its death-knell, namely Fitch's Proof. But, as the final objection makes clear, showing that verificationism can live in the face of Fitch's Proof is one thing; showing that it should live is another project. If nothing else, I hope that this papershows that verificationists still have a project to pursue; Fitch's Proof, contrary to popular opinion, need not bury verificationism.13. (shrink)

: Bereft of the illusion of an epistemic vantage point external to science, what should be our commitment towards the categories, concepts and terms of that very science? Should we, despaired of the possibility to found these concepts on rock bottom, adopt empiricist skepticism? Or perhaps the inexistence of external foundations implies, rather, immunity for scientific ontology from epistemological criticism? Philosophy's "realism debate" died out without providing a satisfactory answer to the dilemma, which was taken over by the neighboring disciplines. (...) The "symmetry principle" of the "StrongProgramme" for the sociology of science-the requirement that truth and error receive the same kind of causal explanations-offered one bold metaphysical answer, under the guise of a methodological decree. Recently, however, it has been argued that this solution is not bold enough, that the social constructivists replaced the naïve presumption of an independent nature which adjudicates our beliefs with a mirror-image presumption of a sui generis society which furnishes these beliefs autonomously. The proper metaphysics for a foundationless epistemology, argues Bruno Latour, is one which grants nature and society, object and subject, equal roles in the success and failure of science and technology; one in which history of society merges with a history of things-in-themselves. The paper analyzes the philosophical and methodological motivations and ramifications of this extraordinary suggestion. (shrink)

I defend a conception of the relationship between the personal and sub-personal levels as interaction withoutreduction.There are downward inferences from the personal to the sub-personal level but we find upward explanatory gaps when we try to construct illuminating accounts of personal level conditions using just sub-personal level notions. This conception faces several serious challenges but the objection that I consider in this paper says that, when theories support downward inferences from the personal to the sub-personal level, this is the product (...) of an unacceptably • mechanistic view of persons. According to this objection, if we were to focus on persons as conscious rational thinkers and agents then the support for putative downward inferences would be undermined. I consider and reject developments of this objection in response to two arguments for downward inferences. (shrink)

According to the anti-Humean theory of motivation, it is possible to be motivated to act by reason alone. According to the Humean theory of motivation, this is impossible. The debate between these two theories remains as vigorous as ever (see for example Pettit 1987, Lewis 1988, Price 1989 and Smith 1994). In this paper I shall argue that the anti-Humean theory of motivation is incompatible with a number of prominent recent theories of content. I shall focus on causal or informational (...) theories of content (such as Dretske 1981, Fodor 1990 and Stalnaker 1984), and on verificationist theories of content (such as Dummett 1993, Putnam 1983 and Wright 1986), though in fact I believe that the same argument applies to several other theories of content as well. (shrink)

Normativism in the theory of meaning and content is the view that linguistic meaning and/or intentional content are essentially normative. As both normativity and its essentiality to meaning/content can be interpreted in a number of different ways, there is now a whole family of views laying claim to the slogan “meaning/content is normative”. In this essay, we discuss a number of central normativist theses, and we begin by identifying different versions of meaning normativism, presenting the arguments that have been put (...) forth for and against them. (shrink)

Although the later Wittgenstein appears as one of the most influential figures in Davidson’s later works on meaning, it is not, for the most part, clear how Davidson interprets and employs Wittgenstein’s ideas. In this paper, I will argue that Davidson’s later works on meaning can be seen as mainly a manifestation of his attempt to accommodate the later Wittgenstein’s basic ideas about meaning and understanding, especially the requirement of drawing the seems right/is right distinction and the way this requirement (...) must be met. These ideas, however, are interpreted by Davidson in his own way. I will then argue that Davidson even attempts to respect Wittgenstein’s quietism, provided that we understand this view in the way Davidson does. Having argued for that, I will finally investigate whether, for Davidson at least, his more theoretical and supposedly explanatory projects, such as that of constructing a formal theory of meaning and his use of the notion of triangulation, are in conflict with this Wittgensteinian quietist view. (shrink)

What is the status of a cat in a virtual reality environment? Is it a real object? Or part of a fiction? Virtual realism, as defended by D. J. Chalmers, takes it to be a virtual object that really exists, that has properties and is involved in real events. His preferred specification of virtual realism identifies the cat with a digital object. The project of this paper is to use a comparison between virtual reality environments and scientific computer simulations to (...) critically engage with Chalmers’s position. I first argue that, if it is sound, his virtual realism should also be applied to objects that figure in scientific computer simulations, e.g. to simulated galaxies. This leads to a slippery slope because it implies an unreasonable proliferation of digital objects. A philosophical analysis of scientific computer simulations suggests an alternative picture: The cat and the galaxies are parts of fictional models for which the computer provides model descriptions. This result motivates a deeper analysis of the way in which Chalmers builds up his realism. I argue that he buys realism too cheap. For instance, he does not really specify what virtual objects are supposed to be. As a result, rhetoric aside, his virtual realism isn’t far from a sort of fictionalism. (shrink)

In this paper, we will discuss what is called the “Manifestation Challenge” to semantic realism, which was originally developed by Michael Dummett and has been further refined by Crispin Wright. According to this challenge, semantic realism has to meet the requirement that knowledge of meaning must be publically manifested in linguistic behaviour. In this regard, we will introduce and evaluate John McDowell’s response to this anti-realistic challenge, which was put forward to show that the challenge cannot undermine realism. According to (...) McDowell, knowledge of undecidable sentences’ truth-conditions can be properly manifested in our ordinary practice of asserting such sentences under certain circumstances, and any further requirement will be redundant. Wright’s further objection to McDowell’s response will be also discussed and it will be argued that this objection fails to raise any serious problem for McDowell’s response and that it is an implausible objection in general. (shrink)

In this paper, I will attempt to develop and defend a common form of intuitive resistance to the companions in guilt argument. I will argue that one can reasonably believe there are promising solutions to the access problem for mathematical realism that don’t translate to moral realism. In particular, I will suggest that the structuralist project of accounting for mathematical knowledge in terms of some form of logical knowledge offers significant hope of success while no analogous approach offers such hope (...) for moral realism. (shrink)

This paper aims to contribute to the analysis of the nature of mathematical modality and hyperintensionality, and to the applications of the latter to absolute decidability. Rather than countenancing the interpretational type of mathematical modality as a primitive, I argue that the interpretational type of mathematical modality is a species of epistemic modality. I argue, then, that the framework of two-dimensional semantics ought to be applied to the mathematical setting. The framework permits of a formally precise account of the priority (...) and relation between epistemic mathematical modality and metaphysical mathematical modality. The discrepancy between the modal systems governing the parameters in the two-dimensional intensional setting provides an explanation of the difference between the metaphysical possibility of absolute decidability and our knowledge thereof. I also advance a topic-sensitive epistemic two-dimensional truthmaker semantics, if hyperintensional approaches are to be preferred to possible worlds semantics. I examine the relation between two-dimensional hyperintensional states and epistemic set theory, providing two-dimensional hyperintensional formalizations of the modal logic of ZFC, large cardinal axioms, $\Omega$-logic, and the Epistemic Church-Turing Thesis. (shrink)

According to Normativism, what an expression means has immediate implications for how a subject should or may (not) employ that expression. Many view this thesis as imposing substantive constraints upon theories of linguistic meaning. In this paper, I shall not consider that view; instead, I shall address the prior issue of whether or not one should accept Normativism. Against certain recent prominent lines of attack common to a number of different anti‐Normativist discussions, I shall defend both the Normativist thesis and (...) an attempt to appeal to a certain platitude in its support. (shrink)

This paper offers a reconstruction of Wittgenstein's discussion on inductive proofs. A "algebraic version" of these indirect proofs is offered and contrasted with the usual ones in which an infinite sequence of modus pones is projected.

According to the “paradox of knowability”, the moderate thesis that all truths are knowable – ... – implies the seemingly preposterous claim that all truths are actually known – ... –, i.e. that we are omniscient. If Fitch’s argument were successful, it would amount to a knockdown rebuttal of anti-realism by reductio. In the paper I defend the nowadays rather neglected strategy of intuitionistic revisionism. Employing only intuitionistically acceptable rules of inference, the conclusion of the argument is, firstly, not ..., (...) but .... Secondly, even if there were an intuitionistically acceptable proof of ..., i.e. an argument based on a different set of premises, the conclusion would have to be interpreted in accordance with Heyting semantics, and read in this way, the apparently preposterous conclusion would be true on conceptual grounds and acceptable even from a realist point of view. Fitch’s argument, understood as an immanent critique of verificationism, fails because in a debate dealing with the justification of deduction there can be no interpreted formal language on which realists and anti-realists could agree. Thus, the underlying problem is that a satisfactory solution to the “problem of shared content” is not available. I conclude with some remarks on the proposals by J. Salerno and N. Tennant to reconstruct certain arguments in the debate on anti-realism by establishing aporias. (shrink)

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 and hyperintensional cognitivism and modal and hyperintensional expressivism. I also develop a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. 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 higher 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 interpretational and objective modalities and the 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 in 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 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 and hyperintensional cognitivism and modal and hyperintensional expressivism. I also develop a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. 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 higher 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 interpretational and objective modalities and the 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 in 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)

Logic: the Basics is an accessible introduction to the core philosophy topic of standard logic. Focussing on traditional Classical Logic the book deals with topics such as mathematical preliminaries, propositional logic, monadic quantified logic, polyadic quantified logic, and English and standard ‘symbolic transitions’. With exercises and sample answers throughout this thoroughly revised new edition not only comprehensively covers the core topics at introductory level but also gives the reader an idea of how they can take their knowledge further and the (...) philosophical questions around logic. -/- Logic: the Basics is essential reading for first-year undergraduate philosophy students on standard introductory logic courses. (shrink)

Alfred Tarski seems to endorse a partial conception of truth, the T-schema, which he believes might be clarified by the application of empirical methods, specifically citing the experimental results of Arne Næss (1938a). The aim of this paper is to argue that Næss’ empirical work confirmed Tarski’s semantic conception of truth, among others. In the first part, I lay out the case for believing that Tarski’s T-schema, while not the formal and generalizable Convention-T, provides a partial account of truth that (...) may be buttressed by an examination of the ordinary person’s views of truth. Then, I address a concern raised by Tarski’s contemporaries who saw Næss’ results as refuting Tarski’s semantic conception. Following that, I summarize Næss’ results. Finally, I will contend with a few objections that suggest a strict interpretation of Næss’ results might recommend an overturning of Tarski’s theory. (shrink)

I propose a pragmatic approach to the kind of reference-shifting occurring in indexicals as used in e.g. written notes and answering machine messages. I proceed in two steps. First, I prepare the ground by showing that the arguments against such a pragmatic approach raised in the recent literature fail. Second, I take a first few steps towards implementing this approach, by sketching a pragmatic theory of reference-shifting, and showing how it can handle cases of the relevant kind. While the immediate (...) scope of the paper is restricted to indexicals and reference-shifting, and the discussion is confined to a specific range of theories and cases, the approach proposed is compatible with a fairly broad range of more or less semantically conservative theories, and many of the conclusions drawn are significant for the evaluation of pragmatic explanations in philosophy more generally. The overall goal is to offer a new perspective on the issues under discussion, and to prompt philosophers to reconsider some of the established methods by which pragmatic explanations are evaluated. (shrink)

Farben sind für uns sowohl objektive, als auch phänomenale Eigenschaften. In seinem Buch argumentiert Fabian Dorsch, daß keine ontologische Theorie der Farben diesen beiden Seiten unseres Farbbegriffes gerecht werden k ann. Statt dessen sollten wir akzeptieren, daß letzterer sich auf zwei verschiedene Arten von Eigenschaften bezieht: die repräsentierten Reflektanzeigenschaften von Gegenständen und die qualitativen Eigenschaften unserer Farbwahrnehmungen, die als sinnliche Gegebenheitsweisen ersterer fungieren. Die Natur der Farben gibt einen detaillierten Überblick über die zeitgenössischen philosophischen und naturwissenschaftlichen Theorien der Farben und (...) bietet sich aufgrund seines systematischen und umfassenden Charakters auch als ein seminar- oder vorlesungsbegleitendes Textbuch an. (shrink)

This dissertation provides a theory of the nature of aesthetic experiences on the basis of a theory of aesthetic values. It results in the formulation of the following necessary conditions for an experience to be aesthetic: it must consist of a representation of an object and an accompanying feeling; the representation must instantiate an intrinsic value; and the feeling must be the recognition of that value and bestow it on the object. Since representations are of intrinsic value for different reasons, (...) there are different kinds of aesthetic experiences . By means of certain conceptual links, it is possible to extend this account to other aesthetic entities thus enabling the formulation of a general theory of the aesthetic in non-aesthetic terms. In particular, aesthetic values are identical with subjective dispositions to elicit aesthetic experiences under normal conditions. Accordingly, I endorse anti-realism about aesthetic values: their existence, nature and exemplification are mind-dependent, while their ascriptions to objects have genuine truth-values. I back up this account by arguing against the alternative positions that either take aesthetic values to be objective or deny the truth-aptness of their attributions. Furthermore, I put forward a relativist variant of anti-realism according to which ascriptions of different aesthetic values to a particular object are all correct, given that the aesthetic experiences involved are made under normal conditions and concern the same aesthetically nonevaluative features of that object. For there is no specifically aesthetic norm by means of which one of the faultless aesthetic experiences can be picked out as the only appropriate one. That aesthetic values nevertheless show a normative dimension is ensured by their conformity to a general account of values as capacities to satisfy, or dissatisfy, rational desires. (shrink)

Explores the stable core of Wittgenstein's philosophy as developed from the Tractatus to the Philosophical Investigations.

Three influential forms of realism are distinguished and interrelated: realism about the external world, construed as a metaphysical doctrine; scientific realism about non-observable entities postulated in science; and semantic realism as defined by Dummett. Metaphysical realism about everyday physical objects is contrasted with idealism and phenomenalism, and several potent arguments against these latter views are reviewed. -/- Three forms of scientific realism are then distinguished: (i) scientific theories and their existence postulates should be taken literally; (ii) the existence of unobservable (...) entities posited by our most successful scientific theories is justified scientifically; and (iii) our best current scientific theories are at least approximately true. It is argued that only some form of scientific realism can make proper sense of certain episodes in the history of science. -/- Finally, Dummett’s influential formulation of semantic issues about realism considered. Dummett argued that in some cases, the fundamental issue is not about the existence of entities, but rather about whether statements of some specified class (such as mathematics) have an objective truth value, independently of our means of knowing it. Dummett famously argued against such semantic realism and in favor of anti-realism. The relation of semantic realism to the metaphysical construal of realism and Dummett’s main argument against semantic realism is examined. (shrink)

This paper offers a new interpretation for Wittgenstein`s treatment of mathematical identities. As it is widely known, Wittgenstein`s mature philosophy of mathematics includes a general rejection of abstract objects. On the other hand, the traditional interpretation of mathematical identities involves precisely the idea of a single abstract object – usually a number –named by both sides of an equation.

Inference versus consequence , an invited lecture at the LOGICA 1997 conference at Castle Liblice, was part of a series of articles for which I did research during a Stockholm sabbatical in the autumn of 1995. The article seems to have been fairly effective in getting its point across and addresses a topic highly germane to the Uppsala workshop. Owing to its appearance in the LOGICA Yearbook 1997 , Filosofia Publishers, Prague, 1998, it has been rather inaccessible. Accordingly it is (...) republished here with only bibliographical changes and an afterword. (shrink)

In his paper ‘Wang’s Paradox’, Michael Dummett provides an argument for why strict finitism in mathematics is internally inconsistent and therefore an untenable position. Dummett’s argument proceeds by making two claims: (1) Strict finitism is committed to the claim that there are sets of natural numbers which are closed under the successor operation but nonetheless have an upper bound; (2) Such a commitment is inconsistent, even by finitistic standards. -/- In this paper I claim that Dummett’s argument fails. I question (...) both parts of Dummett’s argument, but most importantly I claim that Dummett’s argument in favour of the second claim crucially relies on an implicit assumption that Dummett does not acknowledge and that the strict finitist need not accept. (shrink)

After sketching an argument for radical anti-realism that does not appeal to human limitations but polynomial-time computability in its definition of feasibility, I revisit an argument by Wittgenstein on the surveyability of proofs, and then examine the consequences of its application to the notion of canonical proof in contemporary proof-theoretical-semantics.

Normativism in the theory of meaning and content is the view that linguistic meaning and/or intentional content are essentially normative. As both normativity and its essentiality to meaning/content can be interpreted in a number of different ways, there is now a whole family of views laying claim to the slogan “meaning/content is normative”. In this essay, we discuss a number of central normativist theses, and we begin by identifying different versions of meaning normativism, presenting the arguments that have been put (...) forth for and against them. (shrink)

Can an epistemic conception of truth and an endorsement of the excluded middle (together with other principles of classical logic abandoned by the intuitionists) cohabit in a plausible philosophical view? In PART I I describe the general problem concerning the relation between the epistemic conception of truth and the principle of excluded middle. In PART II I give a historical overview of different attitudes regarding the problem. In PART III I sketch a possible holistic solution.

Is linguistic understanding a form of knowledge? I clarify the question and then consider two natural forms a positive answer might take. I argue that, although some recent arguments fail to decide the issue, neither positive answer should be accepted. The aim is not yet to foreclose on the view that linguistic understanding is a form of knowledge, but to develop desiderata on a satisfactory successor to the two natural views rejected here.

I aim to stand the received view about verificationism on its head. It is commonly thought that verificationism is a powerful philosophical tool, which we could deploy very effectively if only it weren’t so hopelessly implausible. On the contrary, I argue. Verificationism - if properly construed - may well be true. But its philosophical applications are chimerical.

State-reduction and the notion of actuality are compared to passage through time and the notion of the present; already in classical relativity the latter give rise to difficulties. The solution proposed here is to treat both tense and value-definiteness as relational properties or facts as relations; likewise the notions of change and probability. In both cases essential characteristics are absent: temporal relations are tenselessly true; probabilistic relations are deterministically true. The basic ideas go back to Everett, although the technical development (...) makes use of the decoherent histories theory of Griffiths, Omnès, and Gell-Mann and Hartle. Alternative interpretations of the decoherent histories framework are also considered. (shrink)

Michael Devitt tells us that metaphysical realism has a kind of immunity from considerations concerning the nature of truth. Part of this immunity comes from Devitt’s insistence that realism is a metaphysical issue, not a semantic one. Most of Devitt’s critics have focused on this point, arguing that a proper understanding of the realism question necessarily involves semantic considerations :65–74, 1991; Miller in Synthese 136:191–217, 2003; Putnam in Comments on Michael Devitt’s ‘Hilary and Me’, in: Baghramian Reading Putnam. Taylor and (...) Francis, Hoboken, 2012; Taylor in Models, truth, and realism. Oxford University Press, New York, 2006). But Devitt also argues at length that semantic considerations should not lead us to give up on realism regardless of whether we admit that the correct characterization of realism is metaphysical in character or not. Devitt’s view hinges on the viability of a strategy which he calls Putting Metaphysics First, which essentially involves giving “a certain temporal and explanatory priority to metaphysical concerns”. Fully explicated, Devitt’s strategy is seen to be based on an epistemological naturalism in the vein of Quine. The main idea is that if we assume a naturalism according to which the only way to know anything is empirically through experience, then we will be able to establish a version of metaphysical realism early on in our investigations. According to Devitt, the empirical evidence for this realism is much stronger than the empirical evidence for the numerous semantical and epistemological views which are put forward in favor of antirealism. So, Devitt argues, we should hold on to the realism that we establish first and build our other theories on top of it. After detailing Devitt’s approach, I offer two objections. The first problem for Devitt is that in the process of putting metaphysics first, he puts epistemological naturalism first. This fact is in tension with his claim that epistemology is a weak starting place and a poor basis of theoretical revision. The second problem is that while our experiences of objects give us evidence that those objects exist, our experiences do not tell us that the objects exist mind-independently in all the ways required for metaphysical realism, or so I contend. Thus, I argue, even if we do put naturalized metaphysics first as Devitt recommends, realism is not secured as a starting point. (shrink)

Are the objects and events that take place in Virtual Reality genuinely real? Those who answer this question in the affirmative are realists, and those who answer in the negative are irrealists. In this paper we argue against the realist position, as given by Chalmers (2017), and present our own preferred irrealist account of the virtual. We start by disambiguating two potential versions of the realist position—weak and strong— and then go on to argue that neither is plausible. We then (...) introduce a Waltonian variety of ictionalism about the virtual, arguing that this sort of irrealist approach avoids the problems of the realist positions, fits with a unifying theory of representational works, and offers a better account of the phenomenology of engaging in virtual experiences. (shrink)

Fitch’s paradox shows, from fairly innocent-looking assumptions, that if there are any unknown truths, then there are unknowable truths. This is generally thought to deliver a blow to antirealist positions that imply that all truths are knowable. The present paper argues that a probabilistic version of antirealism escapes Fitch’s result while still offering all that antirealists should care for.

The pluralist sheds the more traditional ideas of truth and ontology. This is dangerous, because it threatens instability of the theory. To lend stability to his philosophy, the pluralist trades truth and ontology for rigour and other ‘fixtures’. Fixtures are the steady goal posts. They are the parts of a theory that stay fixed across a pair of theories, and allow us to make translations and comparisons. They can ultimately be moved, but we tend to keep them fixed temporarily. Apart (...) from considering rigour of proof as a fixture, I discuss fixed models, invariant notions and fixed information about objects across theories. There are other fixtures, but it is enough to start with these. (shrink)

Drawing on various resources and requirements (as expressed by Dewey, Wittgenstein, Sellars, and Brandom), this paper proposes an externalist view of conceptual mental episodes that does not equate them, even partially, with vehicles of any sort, whether the vehicles be located in the environment or in the head. The social and pragmatic nature of the use of concepts and conceptual content makes it unnecessary and indeed impossible to locate the entities that realize conceptual mental episodes in non-personal or subpersonal contentful (...) entities (vehicles). Persons, who engage in social practices of deontic scorekeeping (Brandom), and who are thus able to produce appropriate inferential behaviour, enact conceptual mental episodes and the basis of their supervenience. (shrink)

Here is one argument against realism. (1) Realists are committed to the classical rules for negation. But (2) legitimate rules of inference must conserve evidence. And (3) the classical rules for negation do not conserve evidence. So (4) realism is wrong. Most realists reject 2. But it has recently been argued that if we allow denied sentences as premisses and conclusions in inferences we will be able to reject 3. And this new argument against 3 generates a new response to (...) the antirealist argument: keep 1 and 2, avoiding 4 by rejecting 3. My aim in this paper is to see how much work in the fight against anti-realism this new response can really do. I argue that there is a powerful objection to the response: 2 is in tension with the claim that denied sentences can be premisses and conclusions in inferences. But I show that, even given this objection, the new response has an important role to play. (shrink)