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)

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)

ABSTRACTEcumenical Alethic Pluralism is a novel kind of alethic pluralism. It is ecumenical in that it widens the scope of alethic pluralism by allowing for a normatively deflated truth property alongside a variety of normatively robust truth properties. We establish EAP by showing how Wright’s Inflationary Arguments fail in the domain of taste, once a relativist treatment of the metaphysics and epistemology of that domain is endorsed. EAP is highly significant to current debates on the nature of truth insofar as (...) it involves a reconfiguration of the dialectic between deflationists and pluralists. (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)

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)

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)

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)

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)

A novel solution to the knowability paradox is proposed based on Kant’s transcendental epistemology. The ‘paradox’ refers to a simple argument from the moderate claim that all truths are knowable to the extreme claim that all truths are known. It is significant because anti-realists have wanted to maintain knowability but reject omniscience. The core of the proposed solution is to concede realism about epistemic statements while maintaining anti-realism about non-epistemic statements. Transcendental epistemology supports such a view by providing for a (...) sharp distinction between how we come to understand and apply epistemic versus non-epistemic concepts, the former through our capacity for a special kind of reflective self-knowledge Kant calls ‘transcendental apperception’. The proposal is a version of restriction strategy: it solves the paradox by restricting the anti-realist’s knowability principle. Restriction strategies have been a common response to the paradox but previous versions face serious difficulties: either they result in a knowability principle too weak to do the work anti-realists want it to, or they succumb to modified forms of the paradox, or they are ad hoc. It is argued that restricting knowability to non-epistemic statements by conceding realism about epistemic statements avoids all versions of the paradox, leaves enough for the anti-realist attack on classical logic, and, with the help of transcendental epistemology, is principled in a way that remains compatible with a thoroughly anti-realist outlook. (shrink)

This volume examines the concept of falsification as a central notion of semantic theories and its effects on logical laws. The point of departure is the general constructivist line of argument that Michael Dummett has offered over the last decades. From there, the author examines the ways in which falsifications can enter into a constructivist semantics, displays the full spectrum of options, and discusses the logical systems most suitable to each one of them. While the idea of introducing falsifications into (...) the semantic account is Dummett's own, the many ways in which falsificationism departs quite radically from verificationism are here spelled out in detail for the first time. The volume is divided into three large parts. The first part provides important background information about Dummett’s program, intuitionism and logics with gaps and gluts. The second part is devoted to the introduction of falsifications into the constructive account and shows that there is more than one way in which one can do this. The third part details the logical effects of these various moves. In the end, the book shows that the constructive path may branch in different directions: towards intuitionistic logic, dual intuitionistic logic and several variations of Nelson logics. The author argues that, on balance, the latter are the more promising routes to take. "Kapsner’s book is the first detailed investigation of how to incorporate the notion of falsification into formal logic. This is a fascinating logico-philosophical investigation, which will interest non-classical logicians of all stripes." Graham Priest, Graduate Center, City University of New York and University of Melbourne. (shrink)

According to Minkoswki, Einstein's special theory of relativity reveals that ‘space by itself, and time by itself are doomed to fade away into mere shadows’. But perceptual experience represents objects as instantiating shapes like squareness — properties of ‘space by itself’. Thus, STR seems to threaten the veridicality of shape experience. In response to this worry, some have argued that we should analyze the contents of our spatial experiences on the model of traditional secondary qualities. On this picture—defended in recent (...) work by Chalmers —an experience of squareness just represents whatever property usually causes such experiences. This view salvages the veridicality of shape experience, but leaves the nature of the properties we perceive outside our ken. I argue that such a move is unwarranted: STR is compatible with the idea that shape experience acquaints us with the spatial character of our world. In defending this claim, I propose a view on which shape experience presents familiar Euclidean spatial properties veridically, while implicitly representing those properties as instantiated in a particular manner — namely, relative to our own frame of reference. (shrink)

This book concerns the foundations of epistemic modality and hyperintensionality and their applications to the philosophy of mathematics. David Elohim examines 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 \textbf{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. Elohim develops a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develops a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. Chapter \textbf{3} provides an abstraction principle for two-dimensional (hyper-)intensions. Chapter \textbf{4} advances a topic-sensitive two-dimensional truthmaker semantics, and provides three novel interpretations of the framework along with the epistemic and metasemantic. Chapter \textbf{5} applies the fixed points of the modal $\mu$-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 $\mu$-calculus are rendered hyperintensional, which yields the first hyperintensional construal of the modal $\mu$-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 \textbf{6} advances a solution to the Julius Caesar problem based on Fine's `criterial' identity conditions which incorporate conditions on essentiality and grounding. Chapter \textbf{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 \textbf{2} and \textbf{4} is availed of in order for epistemic states to be a guide to metaphysical states in the hyperintensional setting. -/- Chapters \textbf{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 \textbf{8} examines the interaction between Elohim's 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 $\Omega$-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 \textbf{9} examines the modal and hyperintensional commitments of abstractionism, in particular necessitism, and epistemic hyperintensionality, epistemic utility theory, and the epistemology of abstraction. Elohim countenances a hyperintensional semantics for novel epistemic abstractionist modalities. Elohim suggests, 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 two-dimensional hyperintensions is grounded in its being possibly recursively enumerable and the machine being physically implementable. Chapter \textbf{10} examines the philosophical significance of hyperintensional $\Omega$-logic in set theory and discusses the hyperintensionality of metamathematics. Chapter \textbf{11} provides a modal logic for rational intuition and provides a hyperintensional semantics. Chapter \textbf{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. Elohim invents 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 \textbf{13} examines modal responses to the alethic paradoxes. Elohim provides a counter-example to epistemic closure for logical deduction. Chapter \textbf{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)

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)

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)

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)

Crispin Wright offers superassertibility as an anti-realist explication of truth. A statement is superassertible, roughly, if there is a state of information available which warrants it and it is warranted by all achievable enlargements of that state of information. However, it is argued, Wright fails to take account of the fact that many of our test procedures are not sure fire, even when applied under ideal conditions. An alternative conception of superassertibility is constructed to take this feature into account. However, (...) it is then argued that when this revised concept of superassertibility is taken as the truth predicate of probability statements, statements whose test procedures are paradigmatically not sure fire, then any anti-realist theory of the sense of such probability statements cannot be compositional, in Dummett's sense of compositional. (shrink)

An increasingly popular moral argument has it that the story of human evolution shows that we can explain the human disposition to make moral judgments without relying on a realm of moral facts. Such facts can thus be dispensed with. But this argument is a threat to moral realism only if there is no realist position that can explain, in the context of human evolution, the relationship between our particular moral sense and a realm of moral facts. I sketch a (...) plausible evolutionary story that illuminates this relationship. First, the sorts of adaptive pressures facing early humans would have produced more than just potent prosocial emotions, as evolutionary antirealists like to claim; it would have produced judgments—often situated within emotions—to the effect that others could reasonably disapprove of some bit of conduct, for an early human who cared deeply about how others might respond to her action enjoyed the benefits of more cooperative exchanges than those early humans who did not. Second, according to objectivist versions of moral constructivism, moral facts just are facts about how others, ideally situated, would respond to one's conduct. Thus if any objectivist moral constructivism story is true, then we can intelligibly assert that a) our capacity for moral judgment is the product of adaptive pressures acting on early humans and b) some moral judgments are objectively true. (shrink)

Frederic Stoutland (1982a, 1982b) has argued that a Davidsonian theory of meaning is incompatible with a realist view of truth, on which the truth-conditions of sentences consist of mind-independent states of affairs or concatenations of extra-linguistic objects. In this paper we show that Stoutland’s argument is a failure.

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.

The connection between theories of truth and meaning is explored. Theories of truth and meaning are connected in a way such that differences in the conception of what it is for a sentence to be true are engendered by differences in the conception of how meanings depend on each other, and on a base of underlying facts. It is argued that this view is common ground between Davidson and Dummett, and that their dispute over realism is really a dispute in (...) the theory of meaning over holism and molecularism. The view offered is contrasted with influential pragmatist and modest views. (shrink)

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 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)

This paper is concerned with connections between scientific and metaphysical realism. It is not difficult to show that scientific realism, as expounded by Psillos (1999) clearly qualifies as a kind of metaphysical realism in the sense of Putnam (1980). The statement of scientific realism therefore must not only deal with underdetermination and the dynamics of scientific theories but also answer the semantic challenges to metaphysical realism. As will be argued, the common core of these challenges is the proposition that a (...) (metaphysical) realist semantics leads to semantic agnosticism in the sense that we are unable to grasp the proper meanings and referents of our linguistic expressions. Having established this, I will focus more specifically on the question of whether scientific realism—in its state-of-the-art account—has the resources to make reference to scientific concepts intelligible such that the semantic challenges can be answered. (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)

Realists claim that, amongst the statements weunderstand, there are some which are true, yetwhose truth potentially transcends the limits ofwhat we can recognize. Dummett and othershave argued that this realist thesis is incompatiblewith an account of understanding in termsof recognitional capacities. But careful analysis revealsthat this contention is mistaken. Thealleged incompatibility presupposes the truth of ametaphysical principle which cannot bevindicated on the basis of an account of understanding.Realists have independent reason toreject this metaphysical principle, as it leads to a collapseof (...) more modest forms of realisminto more contentious ones. According to moderate realism,we neither know that there areactually recognition-transcendent truthsnor do we know taht there are none. Pending apositive case for the metaphysical principle, thisagnosticism is sufficient to warrant therealists' key thesis, viz. that there arepotentially recognition-transcendent truths. Thusrealism, in its more moderate guise, turns outto be the default position. (shrink)

The Manifestation Requirement, advanced by Dummett in his critique of semantic realism, has been criticized for being behavioristic, and the responses have been made that the critics are mistaken. However, the dispute has failed to exhibit the point of the Requirement. In this paper, I shall argue (1) that, in the light of Anscombe's theory of practical knowledge, knowledge of linguistic meaning is to be seen as the knowledge-how that forms the basis of the practical knowledge that an agent has (...) of his own intentional actions, (2) that such knowledge of linguistic meaning is to be based on mutual agreements in a community, and (3) that the Manifestation Requirement is a condition for the possibility of such mutual agreements. As a result, the Manifestation Requirement finds its basis on the idea that language and linguistic acts are tools that we use while continually improving them. (shrink)

This article examines Hilary Putnam's work in the philosophy of mathematics and - more specifically - his arguments against mathematical realism or objectivism. These include a wide range of considerations, from Gödel's incompleteness-theorem and the limits of axiomatic set-theory as formalised in the Löwenheim-Skolem proof to Wittgenstein's sceptical thoughts about rule-following, Michael Dummett's anti-realist philosophy of mathematics, and certain problems – as Putnam sees them – with the conceptual foundations of Peano arithmetic. He also adopts a thought-experimental approach – a (...) variant of Descartes' dream scenario – in order to establish the in-principle possibility that we might be deceived by the apparent self-evidence of basic arithmetical truths or that it might be ‘rational’ to doubt them under some conceivable set of circumstances. Thus Putnam assumes that mathematical realism involves a self-contradictory ‘Platonist’ idea of our somehow having quasi-perceptual epistemic ‘contact’ with truths that in their very nature transcend the utmost reach of human cognitive grasp. On this account, quite simply, ‘nothing works’ in philosophy of mathematics since wecan either cling to that unworkable notion of objective truth or abandon mathematical realism in favour of a verificationist approach that restricts the range of admissible statements to those for which we happen to possess some means of proof or ascertainment. My essay puts the case, conversely, that these hyperbolic doubts are not forced upon us but result from a false understanding of mathematical realism – a curious mixture of idealist and empiricist themes – which effectively skews the debate toward a preordained sceptical conclusion. I then go on to mount a defence of mathematical realism with reference to recent work in this field and also to indicate some problems – as I seethem – with Putnam's thought-experimental approach as well ashis use of anti-realist arguments from Dummett, Kripke, Wittgenstein, and others. (shrink)

There is a widespread opinion that the realist idea that whether a proposition is true or false typically depends on how things are independently of ourselves is bound to turn truth, in Davidson's words, into “something to which humans can never legitimately aspire”. This opinion accounts for the ongoing popularity of “epistemic” theories of truth, that is, of those theories that explain what it is for a proposition (or statement, or sentence, or what have you) to be true or false (...) in terms of some epistemic notion, such as provability, justifiability, verifiability, rational acceptability, warranted assertibility, and so forth, in some suitably characterized epistemic situation. My aim in this paper is to show that the widespread opinion is erroneous and that the (legitimate) epistemological preoccupation with the accessibility of truth does not warrant the rejection of the realist intuition that truth is, at least for certain types of propositions, radically nonepistemic. (shrink)

The thesis includes six essays, each corresponding to a chapter, which have the target of widening the discussion on the limits of knowability through the consideration of some general problematics and the discussion of specific topics. The work is composed of two parts, each of three chapters. In the first part, the discussion is focused on a perspective proper of the philosophy of language. In particular, I consider the discussion on the limits of knowability from the point of view of (...) the debate between semantic realism and antirealism. The second part of the thesis is focused on the discussion on the limits of knowability from a perspective more strictly epistemological and proper of the philosophy of science. (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)

I examine Quine’s and Davidson’s arguments to the effect that classical logic is the one and only correct logic. This conclusion is drawn from their views on radical translation and interpretation, respectively. I focus on the latter, but I first address, independently, Quine’s argument to the effect that the ‘deviant’ logician, who departs from classical logic, is merely changing the subject. Regarding logical pluralism, the question is whether there is more than one correct logic. I argue that bivalence may be (...) subject matter dependent, but that distribution and the law of excluded middle can probably not be dropped whilst maintaining the standard meanings of the connectives. In discussing the ramifications of the indeterminacy of interpretation, I ask whether it forces Davidsonian interpreters to adopt Dummett’s epistemic conception of truth vis-à-vis their interpretations. And, if so, does this cohere with their attributing a nonepistemic notion of truth to their interpretees? This would be a form of logical pluralism. In addition, I discuss Davidson’s arguments against conceptual schemes. Schemes incommensurable with our own could be construed as wholesale deviant logics, or so I argue. And, if so, their possibility would yield, in turn, the possibility of a radical logical pluralism. I also address Davidson’s application of Tarski’s definition of truth. (shrink)

We conceive of many general terms we use as having satisfaction conditions that are objective in that the thought that something meets them neither entails nor is entailed by the thought that we are currently in a position in which we are ready, or warranted, to apply those terms to it. How do we manage to use a given term in such a way that it is thereby endowed, and conceived to be endowed, with satisfaction conditions that are objective in (...) this sense? In the first half of the paper, I present a number of interrelated problems for some extant metasemantical accounts of how use determines objective satisfaction conditions. In the second half, I then propose a novel account that avoids all of these problems. (shrink)

This book concerns the foundations of epistemic modality and hyperintensionality and their applications to the philosophy of mathematics. David Elohim examines 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 \textbf{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. Elohim develops a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develops a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. Chapter \textbf{3} provides an abstraction principle for two-dimensional (hyper-)intensions. Chapter \textbf{4} advances a topic-sensitive two-dimensional truthmaker semantics, and provides three novel interpretations of the framework along with the epistemic and metasemantic. Chapter \textbf{5} applies the fixed points of the modal $\mu$-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 $\mu$-calculus are rendered hyperintensional, which yields the first hyperintensional construal of the modal $\mu$-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 \textbf{6} advances a solution to the Julius Caesar problem based on Fine's `criterial' identity conditions which incorporate conditions on essentiality and grounding. Chapter \textbf{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 \textbf{2} and \textbf{4} is availed of in order for epistemic states to be a guide to metaphysical states in the hyperintensional setting. -/- Chapters \textbf{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 \textbf{8} examines the interaction between Elohim's 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 $\Omega$-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 \textbf{9} examines the modal and hyperintensional commitments of abstractionism, in particular necessitism, and epistemic hyperintensionality, epistemic utility theory, and the epistemology of abstraction. Elohim countenances a hyperintensional semantics for novel epistemic abstractionist modalities. Elohim suggests, 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 two-dimensional hyperintensions is grounded in its being possibly recursively enumerable and the machine being physically implementable. Chapter \textbf{10} examines the philosophical significance of hyperintensional $\Omega$-logic in set theory and discusses the hyperintensionality of metamathematics. Chapter \textbf{11} provides a modal logic for rational intuition and provides a hyperintensional semantics. Chapter \textbf{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. Elohim invents 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 \textbf{13} examines modal responses to the alethic paradoxes. Elohim provides a counter-example to epistemic closure for logical deduction. Chapter \textbf{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 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.

Science and valuation — remarks about the condition of philosophical re ection on science this text is an attempt at a more general look at twentieth‐century philosophical re ection on science conceived as persistent trials to eliminate the non‐eliminateable, i.e. valuations. In this article, I recall the most important concepts of knowledge developed in the twentieth‐century philosophy of science by exposing assumed axiology in, among other things: the Vienna Circle, Karl raimund Popper’s falsi cationism, the historical and social approach of (...) thomas S. Kuhn’s paradigm, and the concept of the ideals of knowledge by Stefan Amsterdamski. I argue that the axiology, and more broadly philosophy is an indelible com‐ ponent of each accepted concept of scienti c knowledge. each concept of knowledge assumes a form of its valuation. (shrink)

In "Revising the Logic of Logical Revision" J. Salerno attempts to undermine Crispin Wright's recent arguments for intuitionism, and to replace Wright and Dummett's arguments with a revisionary argument of his own. I show that Salerno's criticisms of Wright involve both attributing an inference to Wright that no intuitionist would make and fallaciously treating a negative universal as an existential negative. Then I show how very general considerations about the nature of warrant undermine both Wright and Salerno's arguments, when these (...) arguments are applied to discourses with defeasible warrants. While Salerno explicitly restricts his discussion to mathematics, Wright and Dummett intend their revisionary arguments to have much wider scope. (shrink)