The problem of the status of metaphysics -- what it is and what it is for, what use it is - has been with us for millennia, at least since Plato took issue with the Sophists, and continues to the present day. Here I attempt an intervention in this perennial dispute, with the aim of providing some kind of rapprochement between the factions. This intervention is based on how Charles Sanders Peirce (1839-1914) understood metaphysics and the position presented here is (...) thus called `Peircean realism'. The basic idea is that everyone has a metaphysics and has to have one, just to get by in everyday life, and this is no different for scientific inquirers in their professional work. The subject matter of metaphysics is thus presuppositions, whether it is what we rely on to go shopping or to discover the Higgs boson. We rely on these in our activities and expect them to have an effect on outcomes, so when our expectations are frustrated, doubt may be thrown on our presuppositions. We would thus like the ability to inquire into our presuppositions so as not to repeat mistakes, but our instinctive, evolved capacity for reasoning may not be up the job, since it is entwined with what we take for granted. Instead, Peirce develops a science of good reasoning that includes a theory of inquiry, which would allow us to scrutinise our presuppositions, to perform metaphysical inquiry. The starting point for this science of good reasoning is basic principles of combination and organisation, because these are involved in all activity, and these are Peirce's categories of Firstness, Secondness and Thirdness. This is also where I start in the exposition of and argument for Peircean realism as a scientific -- that is, truth-directed -- metaphysics that provides the best possible general presuppositions to the natural and human sciences, the special sciences that deal with matters in their particularity; that Peircean realism is a viable metaphysics for those sciences. This exposition and argument comprises the first part of this thesis. In the second part, the case for Peircean realism is further bolstered by turning a critical eye on positions that are deficient from the Peircean point of view, in that they lack one or other category and thus starve the special sciences of the resources they need, or that they try to ignore metaphysics entirely. All this is meant to demonstrate that metaphysics is unavoidable, that we need all three of Peirce's categories for a viable metaphysics for the special sciences, and that Peircean realism is just such a metaphysics. (shrink)

Paying attention to the inner workings of mathematicians has led to a proliferation of new themes in the philosophy of mathematics. Several of these have to do with epistemology. Philosophers of mathematical practice, however, have not (yet) systematically engaged with general (analytic) epistemology. To be sure, there are some exceptions, but they are few and far between. In this chapter, I offer an explanation of why this might be the case and show how the situation could be remedied. I contend (...) that it is only by conceiving the knowing subject(s) as embodied, fallible, and embedded in a specific context (along the lines of what has been done within social and feminist epistemology) that we can pursue an epistemology of mathematics sensitive to actual mathematical practice. I further suggest that this reconception of the knowing subject(s) does not force us to abandon the traditional framework of epistemology in which knowledge requires justified true belief. It does, however, lead to a fallible conception of mathematical justification that, among other things, makes Gettier cases possible. This shows that topics considered to be far removed from the interests of philosophers of mathematical practice might reveal to be relevant to them. (shrink)

Social metaphysics is a source of important philosophical and moral insight. Furthermore, much social metaphysics appears to be substantive. However, some have recently argued that standard views of metaphysics cannot accommodate substantive social metaphysics. In this paper I offer a new diagnosis of this problem and defend a new solution, showing that this problem is an illuminating lens through which to examine the nature and boundaries of metaphysics. This case instantiates a broad, common pattern generated by attempts to align distinctions (...) between realism and anti-realism, mind-independence and mind-dependence, and legitimate and non-legitimate inquiry. I show that the best response is to abandon the association between substantive metaphysics and mind-independence, and I sketch a new definition of substantivity, given in terms of explanatory power, that makes room for substantive social metaphysics while also offering an attractive basis for general metaphysics. (shrink)

A position that has been called ‘classical indeterminism’ has recently been developed in order to model vagueness: this approach appeals to an object-language ‘determinately’ operator, the semantics of which are defined in such a way as to preserve the principle of bivalence. I suggest that a prominent argument against this strategy, which I call the Field–Williamson argument, fails. The classical indeterminist position in its general form was anticipated by the Aristotelian commentators in their discussions of Aristotle’s famous ‘sea battle’ passage (...) concerning future contingency. But I maintain that, ironically enough, the strategy is less happily applied in this case, where a version of the Field–Williamson argument succeeds. (shrink)

A mental state is luminous if, whenever an agent is in that state, they are in a position to know that they are. Following Timothy Williamson's Knowledge and Its Limits, a wave of recent work has explored whether there are any non‐trivial luminous mental states. A version of Williamson's anti‐luminosity appeals to a safety‐theoretic principle connecting knowledge and confidence: if an agent knows p, then p is true in any nearby scenario where she has a similar level of confidence in (...) p. However, the relevant notion of confidence is relatively underexplored. This paper develops a precise theory of confidence: an agent's degree of confidence in p is the objective chance they will rely on p in practical reasoning. This theory of confidence is then used to critically evaluate the anti‐luminosity argument, leading to the surprising conclusion that although there are strong reasons for thinking that luminosity does not obtain, they are quite different from those the existing literature has considered. In particular, we show that once the notion of confidence is properly understood, the failure of luminosity follows from the assumption that knowledge requires high confidence, and does not require any kind of safety principle as a premise. (shrink)

In this paper, I discuss the currently most popular argument for alethic pluralism, maintaining that the so-called scope problem provides no compelling reason for abandoning the traditional view that truth is one and the same (substantive) property across the various regions of thought or discourse in which it is ascribed or denied to the things we think or say. I disarm the argument by showing that the scope problem does not arise for a number of non-deflationary, monistic views of truth (...) that meet certain semantic and metaphysical constraints, for one can accept any of these views and provide a plausible account of the fact that mental and linguistic tokenings belonging to different regions of discourse involve radically different ways of engaging with reality? from detecting pre-existing facts to constituting them. (shrink)

There is a standard story told about the rise and fall of ordinary language philosophy: it was a widespread, if not dominant, approach to philosophy in Great Britain in the aftermath of World War II up until the early 1960s, but with the development of systematic approaches to the study of language—formal semantic theories on one hand and Gricean pragmatics on the other—ordinary language philosophy more or less disappeared. In this paper we present quantitative evidence to evaluate the standard story (...) of the rise and fall of ordinary language philosophy, building on the topic model of over 30,000 philosophy articles in Weatherson (2022). Using a combination of qualitative judgment and a topic-model-based measurement of similarity between individual articles, we find evidence that supports the first part of the standard story, according to which ordinary language philosophy arises in the 1940s, peaks between the early 1950s and the late 1960s, and then rapidly declines. But we argue that there is also evidence of a "new wave" of ordinary language philosophy in the early 21st century that defies the second part of the standard story. (shrink)

Christopher Hookway has been influential in promoting engagement with pragmatist and naturalist perspectives from classical and contemporary American philosophy. This book reflects on Hookway’s work on the American philosophical tradition and its significance for contemporary discussions of the understanding of mind, meaning, knowledge, and value. -/- Hookway’s original and extensive studies of Charles S. Peirce have made him among the most admired and frequently referenced of Peirce’s interpreters. His work on classical American pragmatism has explored the philosophies of William James, (...) John Dewey, and Josiah Royce, and examined the influence of pragmatist ideas outside of the United States. Additionally, Hookway has participated in a number of celebrated exchanges with some of the most high-profile figures of twentieth- and twenty-first-century philosophy, including Karl-Otto Apel, Philip Pettit, Hilary Putnam, and W.V.O. Quine, through which his treatments of a large range of topics in epistemology and the philosophies of mind and language have been developed and promoted. The chapters in this book—which include contributions from several of Hookway’s former students and colleagues—include studies of Hookway’s engagement with the works of Peirce, James, and Dewey, his contributions to virtue epistemology, and his discussions of hope and pragmatist metaphysics. -/- Pragmatic Reason will be of interest to researchers and advanced students working on American philosophy, the history of analytic philosophy, and epistemology. (shrink)

It seems to be impossible to draw metaphysical conclusions about the world merely from our concepts or our language alone. After all, our concepts alone only concern how we aim to represent the world, not how the world in fact is. In this paper I argue that this is mistaken. We can sometimes draw substantial metaphysical conclusions simply from thinking about how we represent the world. But by themselves such conclusions can be flawed if the concepts from which they are (...) drawn are themselves flawed. I propose that we can overcome these limitations by focusing on a special class of concepts: inescapable concepts. Combining arguments about what the world is like from considerations about our concepts alone, together with an argument that the relevant concepts are inescapable, leads to a novel method for metaphysics, which is broadly neo-Kantian. (shrink)

The view that contradictions cannot be true has been part of accepted philosophical theory since at least the time of Aristotle. In this regard, it is almost unique in the history of philosophy. Only in the last forty years has the view been systematically challenged with the advent of dialetheism. Since Graham Priest introduced dialetheism as a solution to certain self-referential paradoxes, the possibility of true contradictions has been a live issue in the philosophy of logic. Yet, despite the arguments (...) advanced by dialetheists, many logicians and philosophers still hold the opinion that contradictions cannot be true. -/- Rather than advocating the truth of certain contradictions, this thesis offers a different challenge to the classical logician. By showing that it can be philosophically coherent to propose that true contradictions are metaphysically possible, the thesis suggests that the classical logician must do more than she currently has to justify her confidence in the impossibility of true contradictions. Simply fighting off the dialetheist’s putative examples of true contradictions at the actual world isn’t enough to justify the classical logician’s conclusion that true contradictions are impossible. -/- To aid the thesis dialectically, we introduce a new position, absolutism, which hypothesises that it’s metaphysically possible for at least one contradiction to be true, contrasting with the dialetheic hypothesis that some contradictions are true in the actual world. We demonstrate that absolutism can be given a philosophically coherent interpretation, an appropriate logic, and that certain criticisms are completely toothless against absolutism. The challenge put to the classical logician is then: On what logical or philosophical grounds can we rule out the metaphysical possibility of true contradictions? (shrink)

Semantic analysis in early analytic philosophy belongs to a long tradition of adopting geometrical methodologies to the solution of philosophical problems. In particular, it adapts Descartes’ development of formalization as a mechanism of analytic representation, for its application in natural language semantics. This article aims to trace the mathematical roots of Frege, Russel and Carnap’s analytic method. Special attention is paid to the formal character of modern analysis introduced by Descartes. The goal is to identify the particular conception of “form” (...) developed by the analytic tradition, from Descartes to early analytic philosophy, and to determine its relation to similar notions, like ‘function’ and ‘syntax’. Finally, I focus on how Frege, Russell and Carnap’s methods of semantic analysis fit the general characterization of formal analysis previously developed. (shrink)

According to alethic pluralism, sentences belonging to different domains of discourse can be true by having different alethic (i.e., truth-constituting) properties. Against this pluralistic view, Jamin Asay has recently argued that pluralists' appeal to multiple alethic properties is ill-motivated because the main advantages of pluralism can already be obtained within the framework of standard truthmaker theory. In response to this objection, this paper argues that Asay's claim does not hold with respect to one of the central advantages of pluralism, namely, (...) the ability to offer a proper understanding of the realism/anti-realism debate. This is because, first, when simply construed, truthmaker theory can only provide an inadequate understanding of the debate, and second, when construed in certain ways that allow it to avoid inadequacy, it becomes committed to multiple alethic properties. (shrink)

In this short paper, we analyse whether assuming that mathematical objects are “thin” in Linnebo's sense simplifies the epistemology of mathematics. Towards this end, we introduce the notion of transparency and show that not all thin objects are transparent. We end by arguing that, far from being a weakness of thin objects, the lack of transparency of some thin objects is a fruitful characteristic mark of abstract mathematics.

This paper discusses the relation between Crispin Wright’s alethic pluralism and my global expressivism. I argue that on many topics Wright’s own view counts as expressivism in my sense, but that truth itself is a striking exception. Unlike me, Wright never seems to countenance an expressivist account of truth, though the materials needed are available to him in his approaches to other topics.

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)

The article presents a full proof‐theoretic semantics for natural deduction based on an extended inversion principle: the elimination rule for an operator q may invert the introduction rule for q, but also vice versa, the introduction rule for a connective q may invert the elimination rule for q. Such an inversion—extending Prawitz' concept of inversion—gives the following theorem: Inversion for two rules of operator q (intro rule, elim rule) exists iff a reduction of a maximum formula for q exists. The (...) inversion theorem is specified to two logics, Lambek calculus (LC) and intuitionistic linear logic (ILL), with four propositional connectives: two multiplicatives (implication and conjunction) and two additives (conjunction and disjunction), with two quantifiers and two modals. LC is defined by using elimination rules by composition. ILL is defined by using usual general elimination rules. Elimination rules by composition are an exciting alternative to general elimination rules; in some cases, they do not need permutations. (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)

Can it ever be rational to revise one's own logic by one's own lights? In this paper I argue that logic is never rationally revisable, even if one's own logic gives rise to paradoxes and allows one to derive any conclusion whatsoever. Instead of revising logic, we need to revise a certain widely held position in the philosophy of logic, one tied to the standard conception of validity and to the alleged monotonicity of deductive reasoning. I develop the alternative conception (...) of validity and of deductive reasoning, which explains why we are generally entitled to the conclusions of deductive reasoning, even though we rationally do not accept them in certain circumstances tied to paradoxes. (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)

Parsimony considerations are ubiquitous in the literature concerning the nature of mental states. Other things being equal, physicalist views are preferred over dualist accounts on the grounds of the fact that they do not posit new fundamental properties in addition to the physical ones. This paper calls into question the widespread assumption that parsimony can provide reasons for believing that physicalism is a better candidate than dualism for solving the mind–body problem. After presenting the theoretical core of physicalism and dualism, (...) I make explicit the meta-metaphysical assumptions the physicalist relies on when leveraging parsimony to support her view. In particular, the physicalist takes for granted that parsimony has an epistemic value in metaphysics. This point, however, is rather controversial. I argue that the most promising way to account for the epistemic value of parsimony is to ground it in the epistemic value of modesty, a higher-level theoretical virtue that has to do with the epistemic risk of a theory. Unfortunately for the physicalist, the modesty rationale does not ultimately favour physicalism over dualism. (shrink)

I identify two reasons for believing in the objectivity of mathematical knowledge: apparent objectivity and applications in science. Focusing on arithmetic, I analyze platonism and cognitive nativism in terms of explaining these two reasons. After establishing that both theories run into difficulties, I present an alternative epistemological account that combines the theoretical frameworks of enculturation and cumulative cultural evolution. I show that this account can explain why arithmetical knowledge appears to be objective and has scientific applications. Finally, I will argue (...) that, while this account is compatible with platonist metaphysics, it does not require postulating mind-independent mathematical objects. (shrink)

Since Peirce defined the first operators for three-valued logic, it is usually assumed that he rejected the principle of bivalence. However, I argue that, because bivalence is a principle, the strategy used by Peirce to defend logical principles can be used to defend bivalence. Construing logic as the study of substitutions of equivalent representations, Peirce showed that some patterns of substitution get realized in the very act of questioning them. While I recognize that we can devise non-classical notations, I argue (...) that, when we make claims about those notations, we inevitably get saddled with bivalent commitments. I present several simple inferences to show this. The argument that results from those examples is ‘pragmatic’, because the inevitability of the principle is revealed in use (not mention); and it is ‘semiotic’, because this revelation happens in the use of signs. (shrink)

This article aims to show that Wittgenstein’s remarks on religious belief and religious statements can be understood in modest philosophical terms, consistent with the thought that they are neither intended as serving to justify or undermine religious beliefs, nor as the expression of any theorizing about the nature of religious belief or the meaning of religious language. Instead, their philosophical significance is held to consist in their functioning to remind us of what we already know about the latter: such things (...) as in what circumstances one utters religious statements, what the consequences of accepting or rejecting religious beliefs are, and so on. His position is that all attempts to say something more than this are either a mark of philosophical arrogance or a manifestation of one’s own personal commitment to adopting a stance of religious belief or non-belief. As such, they do not furnish us with genuine philosophical insights. I argue that such an interpretation possess two principal merits. Firstly, it demonstrates that there is no tension between Wittgenstein’s remarks on the nature of philosophy and his remarks on religious belief and religious statements. Secondly, it shows that it is possible to philosophize about religion in a manner that does not assume that this has to consist either in presenting an apology for or critique of religion or in formulating philosophical theories regarding the nature of religious belief and the meaning of religious language. (shrink)

While it is common in social epistemology, philosophy of education and sociology to speak of theoretical knowledge, the concept of theoretical knowledge used in ordinary discourse has not been properly examined, and its relations to other types of knowledge remain unclear. This article argues that this ordinary language notion of theoretical knowledge has a distinct meaning different from the meanings of terms for other knowledge types, for example, knowledge‐that, and meta‐cognitive knowledge, and provides an analysis that characterizes theoretical knowledge as (...) distinguished by its indirectness. The article then discusses the implications of this view for the practical role of theoretical knowledge and suggests that a reappraisal of its epistemic significance is due. (shrink)

The text examines the status of the truth in the legal norms, trying to answer the questions of whether they can be subject to a truth assessment and, if such an assessment is possible, how a truth value can be attributed to legal norms. To achieve this goal, first of all, the text discusses some basic linguistic conceptions concerning the nature and truth of legal norms and subsequently, a a complex approach is being proposed for attributing truth-value to legal norms. (...) On On the one hand, the latter’s being studied by the methods of deontic logic and theory of possible worlds, and on the other hand, their relation to truth is being explained by semantic anti-realism. (shrink)

A mental state is luminous if, whenever an agent is in that state, they are in a position to know that they are. Following Timothy Williamson’s Knowledge and Its Limits, a wave of recent work has explored whether there are any non-trivial luminous mental states. A version of Williamson’s anti-luminosity appeals to a safety- theoretic principle connecting knowledge and confidence: if an agent knows p, then p is true in any nearby scenario where she has a similar level of confidence (...) in p. However, the relevant notion of confidence is relatively underexplored. This paper develops a precise theory of confidence: an agent’s degree of confidence in p is the objective chance they will rely on p in practical reasoning. This theory of confidence is then used to critically evaluate the anti-luminosity argument, leading to the surprising conclusion that although there are strong reasons for thinking that luminosity does not obtain, they are quite different from those the existing literature has considered. In particular, we show that once the notion of confidence is properly understood, the failure of luminosity follows from the assumption that knowledge requires high confidence, and does not require any kind of safety principle as a premise. (shrink)

What is the source of logical and mathematical truth? This book revitalizes conventionalism as an answer to this question. Conventionalism takes logical and mathematical truth to have their source in linguistic conventions. This was an extremely popular view in the early 20th century, but it was never worked out in detail and is now almost universally rejected in mainstream philosophical circles. Shadows of Syntax is the first book-length treatment and defense of a combined conventionalist theory of logic and mathematics. It (...) argues that our conventions, in the form of syntactic rules of language use, are perfectly suited to explain the truth, necessity, and a priority of logical and mathematical claims, as well as our logical and mathematical knowledge. (shrink)

The paper defends the argument that the Resemblance Paradox (RP), or the problem of the ‘under-determination of meaning’, and the Rule-Following Paradox (RFP) are two sides of the same paradox threatening meaning from opposite extremes. After presenting the case, the paradox is reconsidered anew and the supposition that the threat is a pervasive one is challenged.

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 \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. 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 \textbf{3} provides an abstraction principle for epistemic (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} are 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 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 $\Omega$-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. 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 \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. 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 \textbf{13} examines modal responses to the alethic paradoxes. I provide a counter-example to epistemic closure for reductio proofs. 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 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 \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. 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 \textbf{3} provides an abstraction principle for epistemic (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} are 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 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 $\Omega$-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. 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 \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. 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 \textbf{13} examines modal responses to the alethic paradoxes. I provide a counter-example to epistemic closure for reductio proofs. 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)

Douglas Edwards is arguably the most prominent contemporary advocate of moderate alethic pluralism. Significantly influenced by Crispin Wright and Michael Lynch, his work on the nature of truth has become widely discussed in the topical literature. Edwards labels his version of moderate alethic pluralism determination pluralism. At first blush, determination pluralism appears philosophically promising. The position deserves thoughtful consideration, particularly because of its capacity to accommodate the scope problem. I argue, however, that upon analysis the view is better understood as (...) a form of metaphysical dualism or what I will call meta-dualism. Furthermore, determination pluralists face a dilemma; there appears to be an instability at the core of their dualistic model. On the one horn of the dilemma, they need a clear metaphysical demarcation at the interface of their two necessary domains. On the other horn, they seem to need to a metaphysically vague boundary at the interface of their two necessary domains. Determination pluralism needs substantial revision. (shrink)

Wittgenstein's paradoxical theses that unproved propositions are meaningless, proofs form new concepts and rules, and contradictions are of limited concern, led to a variety of interpretations, most of them centered on rule-following skepticism. We argue, with the help of C. S. Peirce's distinction between corollarial and theorematic proofs, that his intuitions are better explained by resistance to what we call conceptual omniscience, treating meaning as fixed content specified in advance. We interpret the distinction in the context of modern epistemic logic (...) and semantic information theory, and show how removing conceptual omniscience helps resolve Wittgenstein's paradoxes and explain the puzzle of deduction, its ability to generate new knowledge and meaning. (shrink)

Semantic realism can be characterised as the idea that scientific theories are truth-bearers, and that they are true or false in virtue of the world. This notion is often assumed, but rarely discussed in the literature. I examine how it fares in the context of the semantic view of theories and in connection with the literature on scientific representation. Making sense of semantic realism requires specifying the conditions of application of theoretical models, even for models that are not actually used, (...) which leads to several difficulties. My conclusion is that semantic realism is far more demanding than one would expect. Finally, I briefly examine some pragmatist alternatives. (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)

Michael Dummett has proposed an influential analysis of the meaning of ethnic and racial slurs based on inferential rules. Timothy Williamson, however, finds the analysis problematic. It does not seem to explain how slurs are actually used. Williamson’s challenge for the inferentialist account of slurs has not gone unnoticed. In this article, I first discuss the debate between the inferentialists and Williamson. I argue that the inferentialist responses concentrate on the wrong issue and the real issue in Williamson’s challenge is (...) left untouched. I go on to specify his challenge and offer a solution to the challenge. The solution rests on the idea that the inferential rules for slurs involve a generic component. (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)

The Logocratic Method, and the Logocratic theory that underwrites it, provide a philosophical explanation of three purposes or goals that arguers have for their arguments: to make arguments that are internally strong, or that are dialectically strong, or that are rhetorically strong. This article presents the basic terms and methods of Logocratic analysis and then uses a case study to illustrate the Logocratic explanation of arguments. Highlights of this explanation are: the use of a virtue framework to explicate the three (...) strengths and weaknesses of arguments that are of greatest interest to arguers in many contexts, the Logocratic explication of the structure of abduction generally and of legal abduction specifically, the concept of a system of arguments, and the concept of the dynamic interactive virtue of arguments—a property of systems of arguments in which the system of arguments as a whole is as virtuous as are the component arguments that comprise the system. This is especially important since, according to Logocratic theory, some arguments, such as abduction and analogical argument, are themselves comprised of different logical forms. (shrink)

The answers to the questions in the title depend on the kind of pluralism one is talking about. We will focus here on our own views. The purpose of this article is to trace out some possible connections between these kinds of pluralism. We show how each of them might bear on the other, depending on how certain open questions are resolved.

This essay presents a long, detailed, in many ways critical but also appreciative account, of David Bloor’s recent book The Enigma of the Aerofoil. I take that work as the crowning statement of ideas and principles developed over the past four decades by Bloor and other exponents of the ‘strong programme’ in the sociology of scientific knowledge. It therefore offers both a test-case of that approach and a welcome opportunity to review, clarify and extend some of the arguments brought against (...) it by critical realists. This purpose is particularly well served by Bloor’s having here assembled such a wealth of scientific, historical, political and socio-cultural data concerning one specific, very crucial period of research into theories of aerodynamic lift. His book thus provides an exceptionally useful point of engagement for anyone seeking to adjudicate these issues from a critically angled but engaged and constructive standpoint. (shrink)

Logical pluralists are committed to the idea of a neutral metalanguage, which serves as a framework for debates in logic. Two versions of this neutrality can be found in the literature: an agreed upon collection of inferences, and a metalanguage that is neutral as such. I discuss both versions and show that they are not immune to Quinean criticism, which builds on the notion of meaning. In particular, I show that the first version of neutrality is sub-optimal, and hard to (...) reconcile with the theories of meaning for logical constants, and the second version collapses mathematically, if rival logics, as object languages, are treated with charity in the metalanguage. I substantiate by proving a collapse theorem that generalizes familiar results. Thus, the existence of a neutral metalanguage cannot be taken for granted, and meaning-invariant logical pluralism might turn out to be dubious. (shrink)

There is no interesting entailment either way between theism and various forms of realism. Taking its cue from Dummett’s characterisation of realism and his discussion of it with respect to theistic belief, this paper argues both that theism does not follow from realism, and that God cannot be appealed to in order to secure bivalence for an otherwise indeterminate subject matter. In both cases, significant appeal is made to the position that God is not a language user, which in turn (...) is motivated by an account of understanding as aptitude possession. The resulting picture sits comfortably with the apophatism common within living religious traditions and with the view that the philosophy of religion ought to reorientate itself away from metaphysics towards more practical questions. (shrink)

Questions embedded under responsive predicates and definite descriptions both give rise to a variety of phenomena which can be grouped under the term plurality effects: quantificational variability, cumulativity, and homogeneity effects. This similarity has not gone unnoticed, and many proposals have taken inspiration in theories of definite plurals to account for these effects with embedded questions. Recently these phenomena have received less attention, as the field has focused on the so-called intermediate exhaustive reading of embedded questions instead, after Spector called (...) into question the traditional dichotomy between weak and strong exhaustive readings. As a result, the intermediate exhaustive reading has been accounted for at the expense of empirical coverage in other areas. In this paper, I propose a modular theory which derives the currently much discussed exhaustive readings without giving up the rich semantics necessary to account for plurality effects. My account of quantificational variability, cumulativity, and homogeneity effects builds on recent work on these phenomena in the nominal domain by adopting a categorial approach to embedded questions, while the strong and intermediate exhaustive readings are implemented using an independent strengthening mechanism suggested in Klinedinst and Rothschild :1–23, 2011). The resulting theory not only recovers important results on plurality effects; it offers new, simple solutions for some puzzles presented in George :166–177, 2013) and Paillé and Schwarz Proceedings of WCCFL 36, vol 36, Cascadilla Proceedings Project, Somerville, 2018), naturally derives readings that had been postulated in previous literature, makes correct predictions in many unexplored cases, and is compatible with recent results in psycholinguistics. In the last sections I justify my assumptions and show how possible limitations I inherit from the theories I build on can be accommodated under standard assumptions. (shrink)

Dummett’s notion of indefinite extensibility is influential but obscure. The notion figures centrally in an alternative Dummettian argument for intuitionistic logic and anti-realism, distinct from his more famous, meaning-theoretic arguments to the same effect. Drawing on ideas from Dummett, a precise analysis of indefinite extensibility is proposed. This analysis is used to reconstruct the poorly understood alternative argument. The plausibility of the resulting argument is assessed.

In response to Hirsch's deflationary arguments, Sider attempts to introduce a special Ontologese quantifier to preserve the substantivity of fundamental debates in metaphysics. He claims that this strategy can be effected by two distinct means, one of which is a list of instructions for metaphysicians, which he argues suffice to give the new quantifier a meaning that carves nature at the joints. I argue that these instructions will not allow someone to start speaking Ontologese if their prior language is sufficiently (...) deviant with respect to it, and that natural languages may be in just such a position. (shrink)

Esta enciclopédia abrange, de uma forma introdutória mas desejavelmente rigorosa, uma diversidade de conceitos, temas, problemas, argumentos e teorias localizados numa área relativamente recente de estudos, os quais tem sido habitual qualificar como «estudos lógico-filosóficos». De uma forma apropriadamente genérica, e apesar de o território teórico abrangido ser extenso e de contornos por vezes difusos, podemos dizer que na área se investiga um conjunto de questões fundamentais acerca da natureza da linguagem, da mente, da cognição e do raciocínio humanos, bem (...) como questões acerca das conexões destes com a realidade não mental e extralinguística. A razão daquela qualificação é a seguinte: por um lado, a investigação em questão é qualificada como filosófica em virtude do elevado grau de generalidade e abstracção das questões examinadas (entre outras coisas); por outro, a investigação é qualificada como lógica em virtude de ser uma investigação logicamente disciplinada, no sentido de nela se fazer um uso intenso de conceitos, técnicas e métodos provenientes da disciplina de lógica. O agregado de tópicos que constitui a área de estudos lógico-filosóficos é já visível, pelo menos em parte, no Tractatus Logico-Philosophicus de Ludwig Wittgenstein, uma obra publicada em 1921. E uma boa maneira de ter uma ideia sinóptica do território disciplinar abrangido por esta enciclopédia, ou pelo menos de uma porção substancial dele, é extrair do Tractatus uma lista dos tópicos mais salientes aí discutidos; a lista incluirá certamente tópicos do seguinte género, muitos dos quais se podem encontrar ao longo desta enciclopédia: factos e estados de coisas; objectos; representação; crenças e estados mentais; pensamentos; a proposição; nomes próprios; valores de verdade e bivalência; quantificação; funções de verdade; verdade lógica; identidade; tautologia; o raciocínio matemático; a natureza da inferência; o cepticismo e o solipsismo; a indução; as constantes lógicas; a negação; a forma lógica; as leis da ciência; o número. (shrink)

In recent years an increasing number of psychologists have begun to explore the prevalence, causes and effects of ordinary people’s intuitions about moral realism. Many of these studies have lacked in construct validity, i.e., they have failed to measure moral realism. My aim in this paper accordingly is to motivate and guide methodological improvements. In analysis of prominent existing measures, I develop general recommendations for overcoming ten prima facie serious worries about research on folk moral realism. G1 and G2 require (...) studies’ answer choices to be as metaethically comprehensive as methodologically feasible. G3 and G4 prevent fallacious inferences from intuitions about related debates. G5 and G6 limit first-order moral and epistemic influences. G7 address studies’ instructions. And G8 and G9 suggest tests of important psychological presuppositions. (shrink)

Berkeley’s ‘master argument’ for idealism has been the subject of extensive criticism. Two of his strongest critics, A.N. Prior and J.L. Mackie, argue that due to various logical confusions on the part of Berkeley, the master argument fails to establish his idealist conclusion. Prior argues that Berkeley’s argument ‘proves too little’ in its conclusion, while Mackie contends that Berkeley confuses two different kinds of self-refutation in his argument. This paper proposes a defence of the master argument based on intuitionistic argument. (...) It begins by giving a brief exposition of the master argument and Prior's and Mackie's criticism. The following section explains why we might read the master argument along intuitionistic lines. The final section demonstrates that, according to intuitionistic logic, Berkeley's argument withstands the criticisms of Prior and Mackie. (shrink)