This book takes purism about knowledge as the default position and defends it from the challenges of pragmatic encroachment. The book is divided into two parts, a negative and a positive one. The negative part critically examines existing purist strategies in response to pragmatic encroachment. The positive part provides a new theory of how practical factors can systematically influence our confidence and explores some implications of such influence. In particular, it provides a new purist explanation of the data commonly used (...) to motivate pragmatic encroachment on knowledge. Moreover, it develops a new variety of pragmatic encroachment, not on knowledge but on credence. Thus, my aim in this book is not to provide a full-fledged defence of all kinds of purism. Rather, I argue for purism about knowledge but pragmatic encroachment about credence. This book is a revised version of my PhD dissertation “Belief, Knowledge and Action”. In this revision, I have made some substantive changes, introduced some stylistic changes and added discussions of new relevant literature. (shrink)

This essay aims to provide a modal logic for rational intuition. Similarly to treatments of the property of knowledge in epistemic logic, I argue that rational intuition can be codified by a modal operator governed by the modal $\mu$-calculus. Via correspondence results between fixed point modal propositional logic and the bisimulation-invariant fragment of monadic second-order logic, a precise translation can then be provided between the notion of 'intuition-of', i.e., the cognitive phenomenal properties of thoughts, and the modal operators regimenting the (...) notion of 'intuition-that'. I argue that intuition-that can further be shown to entrain conceptual elucidation, by way of figuring as a dynamic-interpretational modality which induces the reinterpretation of both domains of quantification and the intensions and hyperintensions of mathematical concepts that are formalizable in monadic first- and second-order formal languages. Hyperintensionality is countenanced via a topic-sensitive epistemic two-dimensional truthmaker semantics. (shrink)

We think of logic as objective. We also think that we are reliable about logic. These views jointly generate a puzzle: How is it that we are reliable about logic? How is it that our logical beliefs match an objective domain of logical fact? This is an instance of a more general challenge to explain our reliability about a priori domains. In this paper, I argue that the nature of this challenge has not been properly understood. I explicate the challenge (...) both in general and for the particular case of logic. I also argue that two seemingly attractive responses – appealing to a faculty of rational insight or to the nature of concept possession – are incapable of answering the challenge. (shrink)

I argue that you can have a priori knowledge of propositions that neither are nor appear necessarily true. You can know a priori contingent propositions that you recognize as such. This overturns a standard view in contemporary epistemology and the traditional view of the a priori, which restrict a priori knowledge to necessary truths, or at least to truths that appear necessary.

Philosophers traditionally recognize two main features of mental states: intentionality and phenomenal consciousness. To a first approximation, intentionality is the aboutness of mental states, and phenomenal consciousness is the felt, experiential, qualitative, or "what it's like" aspect of mental states. In the past few decades, these features have been widely assumed to be distinct and independent. But several philosophers have recently challenged this assumption, arguing that intentionality and consciousness are importantly related. This article overviews the key views on the relationship (...) between consciousness and intentionality and describes our favored view, which is a version of the phenomenal intentionality theory, roughly the view that the most fundamental kind of intentionality arises from phenomenal consciousness. (shrink)

In this paper, I explore a question about deductive reasoning: why am I in a position to immediately infer some deductive consequences of what I know, but not others? I show why the question cannot be answered in the most natural ways of answering it, in particular in Descartes’s way of answering it. I then go on to introduce a new approach to answering the question, an approach inspired by Hume’s view of inductive reasoning.

According to foundationalism, some beliefs are justified but do not depend for their justification on any other beliefs. According to access internalism, a subject is justified in believing some proposition only if that subject is aware of or has access to some reason to think that the proposition is true or probable. In this paper I discusses a fundamental challenge to internalist foundationalism often referred to as the Sellarsian dilemma. I consider three attempts to respond to the dilemma – phenomenal (...) conservatism, BonJour’s classical foundationalism, and Fumerton’s classical foundationalism. I argue that, of these three, only the last seems to avoid getting impaled on one or the other horn of the dilemma. I end by responding to some concerns with Fumerton’s account. (shrink)

Defenders of pragmatic encroachment in epistemology (or what I call practicalism) need to address two main problems. First, the view seems to imply, absurdly, that knowledge can come and go quite easily—in particular, that it might come and go along with our variable practical interests. We can call this the stability problem. Second, there seems to be no fully satisfying way of explaining whose practical interests matter. We can call this the “whose stakes?” problem. I argue that both problems can (...) be addressed in roughly the same terms. More exactly, I argue that by first clarifying the whose stakes? problem an answer to the stability problem naturally falls out. (shrink)

My purpose in this paper is to examine the role of intuition in conceptual analysis and to assess whether that role can be parlayed into a plausible defense of a priori knowledge. The focus of my investigation is George Bealer’s attempt to provide such a defense. I argue that Bealer’s account of intuition and its evidential status faces three problems. I go on to examine the two primary arguments that Bealer offers against empiricism: the Starting Points Argument and the Argument (...) from Epistemic Norms. I argue that the Starting Points Argument fails because Bealer fails to show that intuitions are a priori evidence and that the Argument from Epistemic Norms fails because it is open to the Stalemate Problem. I conclude by offering an alternative approach to defending the a priori status of intuitions that avoids the Stalemate Problem. The alternative approach highlights the role of empirical investigation in defending the a priori. (shrink)

The distinction between a priori knowledge and a posteriori knowledge has come under attack in the recent literature by Philip Kitcher, John Hawthorne, C. S. Jenkins, and Timothy Williamson. Evaluating the attacks requires answering two questions. First, have they hit their target? Second, are they compelling? My goal is to argue that the attacks fail because they miss their target. Since the attacks are directed at a particular concept or distinction, they must accurately locate the target concept or distinction. Accurately (...) locating the target concept or distinction requires correctly articulating that concept or distinction. The attacks miss their target because they fail to correctly articulate the target concept or distinction. I go on to present a different challenge to the a priori-a posteriori distinction. This challenge is not directed at the coherence or significance of the distinction. Its target is the traditional view that all knowledge (or justified belief) is either a priori or a posteriori. (shrink)

Priest holds anti-exceptionalism about logic. That is, he holds that logic, as a theory, does not have any exceptional status in relation to the theories of empirical sciences. Crucial to Priest’s anti-exceptionalism is the existence of ‘data’ that can force the revision of logical theory. He claims that classical logic is inadequate to the available data and, thus, needs to be revised. But what kind of data can overturn classical logic? Priest claims that the data is our intuitions about the (...) validity of inferences. In order to make sense of this claim, I will appeal to the Madhyamaka Buddhist philosopher Candrakīrti. I will then pose a problem for Priest’s anti-exceptionalism. Finally, I will suggest a way out of the problem for Priest. Whether or not he accepts my solution, I will let him decide. (shrink)

Much discussion about experimental philosophy and philosophical methodology has been framed in terms of the reliability of intuitions, and even when it has not been about reliability per se, it has been focused on whether intuitions meet whatever conditions they need to meet to be trustworthy as evidence. But really that question cannot be answered independently from the questions, evidence for what theories arrived at by what sorts of inferences? I will contend here that not just philosophy's sources of evidence, (...) but also its inferential resources, are in great need of closer examination. (shrink)

The most pressing worry for panpsychism is arguably the combination problem, the problem of intelligibly explaining how the experiences of microphysical entities combine to form the experiences of macrophysical entities such as ourselves. This chapter argues that the combination problem is similar in kind to other problems of mental combination that are problems for everyone: the problem of phenomenal unity, the problem of mental structure, and the problem of new quality spaces. The ubiquity of combination problems suggests the ignorance hypothesis, (...) the hypothesis that we are ignorant of certain key facts about mental combination, which allows the panpsychist to avoid certain objections based on the combination problem. (shrink)

In this paper, I consider an argument for the claim that any satisfactory epistemology of mathematics will violate core tenets of naturalism, i.e. that mathematics cannot be naturalized. I find little reason for optimism that the argument can be effectively answered.

The distinction between the a priori and the a posteriori is an old and influential one. But both the distinction itself and the crucial notion of a priori knowledge face powerful philosophical challenges. Many philosophers worry that accepting the a priori is tantamount to accepting epistemic magic. In contrast, this Element argues that the a priori can be formulated clearly, made respectable, and used to do important epistemological work. The author's conception of the a priori and its role falls short (...) of what some historical proponents of the notion may have hoped for, but it allows us to accept and use the notion without abandoning either naturalism or empiricism, broadly understood. This Element argues that we can accept and use the a priori without magic. (shrink)

Empiricist philosophers like Carnap invoked analyticity in order to explain a priori knowledge and necessary truth. Analyticity was “truth purely in virtue of meaning”. The view had a deflationary motivation: in Carnap’s proposal, linguistic conventions alone determine the truth of analytic sentences, and thus there is no mystery in our knowing their truth a priori, or in their necessary truth; for they are, as it were, truths of our own making. Let us call this “Carnapian conventionalism”, conventionalismC and cognates for (...) short. This conventionalistC explication of the a priori has been the target of sound criticisms. Arguments like Quine’s in “Truth by Convention” are in our view decisive: the truth of conventionalismC requires that the class of logical truths and logical validities be reductively accounted for as conventionally established; however, no such reduction is forthcoming, because logic is needed to generate the entire class from any given set of conventions properly so-called. Granted that conventionalismC is untenable, we want to take issue with a different, usually made criticism. Although the argument uncovers some difficulties for the way conventionalist claims are defended by some of its advocates, we will try to show that it fails. The criticism thus stands in the way of a proper appreciation of why the Carnapian account of the a priori is not correct. We will try to illustrate this by showing that the criticism we will dispute would dispose of conventionalist claims not only regarding philosophically problematic cases – logical and mathematical truths –, but also regarding cases for which they have some prima facie plausibility. One such case is that of truths that follow from mere abbreviations, “nominal” definitions; ‘someone is a bachelor if and only if he is an unmarried adult male’ can serve at this point for illustration. We will try to articulate a clear sense in which the contents of assertion such as this can be truths by convention. We do not need to prove that a conventionalist claim is true in those cases; it is enough for us to show that it is intelligible, for the arguments we will confront question even this. (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)

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)

Approaching Infinity addresses seventeen paradoxes of the infinite, most of which have no generally accepted solutions. The book addresses these paradoxes using a new theory of infinity, which entails that an infinite series is uncompletable when it requires something to possess an infinite intensive magnitude. Along the way, the author addresses the nature of numbers, sets, geometric points, and related matters. The book addresses the need for a theory of infinity, and reviews both old and new theories of infinity. It (...) discussing the purposes of studying infinity and the troubles with traditional approaches to the problem, and concludes by offering a solution to some existing paradoxes. (shrink)

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

This paper explores the relationship between phenomenal properties and intentional properties. In recent years a number of philosophers have argued that intentional properties are sometimes necessitated by phenomenal properties, but have not explained why or how. Exceptions can be found in the work of Katalin Farkas and Farid Masrour, who develop versions of reductionism regarding phenomenally-necessitated intentionality (or "phenomenal intentionality"). I raise two objections to reductive theories of the sort they develop. Then I propose a version of primitivism regarding phenomenal (...) intentionality. I argue that primitivism avoids the pitfalls of reductionism while promising broad explanatory payoffs. (shrink)

The debate between exceptionalists and anti-exceptionalists about logic is often framed as concerning whether the justification of logical theories is a priori or a posteriori (for short: whether logic is a priori or a posteriori). As we substantiate (S1), this framing more deeply encodes the usual anti-exceptionalist thesis that logical theories, like scientific theories, are abductively justified, coupled with the common supposition that abduction is an a posteriori mode of inference, in the sense that the epistemic value of abduction is (...) (and, indeed, must be) a posteriori. In past work, however, we have argued that this common supposition is incorrect: abduction is an a priori mode of inference, in the sense that the epistemic value of abduction is (and indeed, must be) a priori (Biggs and Wilson 2017a, 2017b, 2019). After sketching our two main argumentative strategies for this conclusion (S2), we go on (S3) to consider its import on the proper understanding of anti-exceptionalism about logic. (shrink)

This paper argues that a priori justification is, in principle, compatible with naturalism—if the a priori is understood in a way that is free of the inessential properties that, historically, have been associated with the concept. I argue that empirical indefeasibility is essential to the primary notion of the a priori ; however, the indefeasibility requirement should be interpreted in such a way that we can be fallibilist about apriori-justified claims. This fallibilist notion of the a priori accords with the (...) naturalist’s commitment to scientific methodology in that it allows for apriori-justified claims to be sensitive to further conceptual developments and the expansion of evidence. The fallibilist apriorist allows that an a priori claim is revisable in only a purely epistemic sense. This modal claim is weaker than what is required for a revisability thesis to establish empiricism, so fallibilist apriorism represents a distinct position. (shrink)

I give a brief overview of Albert Casullo’s Essays on A Priori Knowledge and Justification (2012), followed by a summary of his diagnostic framework for evaluating accounts of a priori knowledge and a priori justification. I then discuss Casullo’s strategy for countering deficiency arguments against empiricism. A deficiency argument against empiricism can be countered by mounting a parallel argument against moderate rationalism that shows moderate rationalism to be defective in a similar way. I argue that a particular deficiency argument put (...) forth by George Bealer in “The Incoherence of Empiricism” (1992) can withstand a parallel challenge mounted by Casullo (2012, Ch.6). -/- I then consider Casullo’s preferred analysis of the concept of a priori justification, which identifies a belief’s being justified by some nonexperiential source as the feature by virtue of which it is justified a priori. On the analysis, an apriori-justfied belief that is justified to a degree that is sufficient for knowledge is not taken to be empirically indefeasible. I argue that Casullo could avail himself of an empirical indefeasibility requirement that is consistent with his minimal and fallibilist conception of a priori knowledge. Doing so would capture a feature of the concept of a priori knowledge that is of particular interest and significance. (shrink)

_ Source: _Page Count 29 Underdetermination arguments for skepticism maintain that our common sense view of the external world is no better, evidentially speaking, than some skeptical competitors. An important and well-known response by dogmatists, those who believe our commonsense view is justified, appeals to abduction or inference to the best explanation. The predominant version of this strategy, going back at least to Locke, invokes Occam’s razor: dogmatists claim the common sense view is simpler than any of its skeptical alternatives (...) and so has more to recommend it, evidentially speaking. This dispute has overshadowed another possible view: skeptical dogmatism. Skeptical dogmatists hold that we are justified in believing that the common sense view is probably false. I argue that skeptical dogmatism presents some interesting complications to the dialectic between the dogmatist and the skeptic. On the one hand, even if the dogmatist’s use of Occam’s razor is sufficient to rebut skepticism, in itself it is not sufficient to refute skeptical dogmatism. On the other hand, skeptics themselves, ironically, must, given the assumptions of the paper, appeal to something like Occam’s razor in order to avoid capitulating to skeptical dogmatism. (shrink)

Sextus Empiricus offers an underappreciated and under-discussed version of dream-based skepticism. Most philosophers interested in dreams and skepticism focus on the question of how you know you are not currently dreaming. Sextus points out that our waking experiences and dreams often conflict. And, the challenge goes, what reason do you have to trust the one over the other? This question presupposes that dreams and waking experiences are distinguishable. Thus the kinds of responses typically offered against dream-based skepticism do not apply. (...) And if we accept an idea upheld by one camp in the contemporary debate over the epistemology of disagreement, Sextus’ challenge is difficult to answer. A G.E. Moore-inspired response to the problem is also proposed and explored. It is argued that Sextus’ version of the problem reveals a certain limitation in that sort of approach to skeptical problems. (shrink)

A self-fulfilling fallacy (SFF) is a fallacious argument whose conclusion is that the very fallacy employed is an invalid or otherwise illegitimate inferential procedure. This paper discusses three different ways in which SFF’s might serve to justify their conclusions. SFF’s might have probative value as honest and straightforward arguments, they might serve to justify the premise of a meta-argument or, following a point made by Roy Sorensen, they might provide a non-inferential basis for accepting their conclusion. The paper concludes with (...) an assessment of the relative merits of these proposals. (shrink)

This paper argues that reading is a source of knowledge. Epistemologists have virtually ignored reading as a source of knowledge. This paper argues, first, that reading is not to be equated with attending to testimony, and second that it cannot be reduced to perception. Next an analysis of reading is offered and the source of knowledge that reading is further delineated. Finally it is argued that the source that reading is, can be both transmissive and generative, is non-basic, once was (...) a non-essential but has become essential for many people, and can be unique. (shrink)

There are three theories in the epistemology of modality that have received sustained attention over the past 20 years: conceivability-theory, counterfactual-theory, and deduction-theory. In this paper we argue that all three face what we call the problem of modal epistemic friction. One consequence of the problem is that for any of the three accounts to yield modal knowledge, the account must provide an epistemology of essence. We discuss an attempt to fend off the problem within the context of the internalism (...) versus externalism debate about epistemic justification. We then investigate the effects that the PMEF has on reductive and non-reductive theories of the relation between essence and modality. (shrink)

I argue that Quinean naturalists’ holism-based arguments against analyticity and apriority are more difficult to resist than is generally supposed, for two reasons. First, although opponents of naturalism sometimes dismiss these arguments on the grounds that the holistic premises on which they depend are unacceptably radical, it turns out that the sort of holism required by these arguments is actually quite minimal. And second, although it’s true, as Grice and Strawson pointed out long ago, that these arguments can succeed only (...) if there isn’t any principled criterion for meaning change, such a criterion turns out to be hard to come by. David Chalmers has recently argued that such a criterion must exist, since the norms governing belief revision are subject to obvious exceptions that can be explained only by appeal to meaning change. But this, I argue, is incorrect: if choices about how to use language are themselves rationally assessable, then there are no such exceptions to be explained. To show that this is so, I formulate a new kind of coherence norm that may be useful for reasoning formally about the relationship between meaning and evidence. (shrink)

Truth by convention, once thought to be the foundation of a uniquely promising approach to explaining our access to the truth in nonempirical domains, is nowadays widely considered an absurdity. Its fall from grace has been due largely to the influence of an argument that can be sketched as follows: our linguistic conventions have the power to make it the case that a sentence expresses a particular proposition, but they can’t by themselves generate truth; whether a given proposition is true—and (...) so whether the sentence that expresses it is true—is a matter of what the world is like, which means it isn’t a matter of convention alone. The consensus is that this argument is decisive against truth by convention. Strikingly, though, it has rarely been formulated with much precision. Here I provide a new rendering of the argument, one that reveals its structure and makes transparent just what assumptions it requires, and then I assess conventionalists’ prospects for resisting each of those assumptions. I conclude that the consensus is mistaken: contrary to what is almost universally thought, there remains a promising way forward for the conventionalist project. Along the way, I clarify conventionalists’ commitments by thinking about what truth by convention would need to be like in order for conventionalism to do the epistemological work it’s intended to do. (shrink)

Paul Benacerraf’s argument that mathematical realism is apparently incompatible with mathematical knowledge has been widely thought to also show that a priori knowledge in general is problematic. Although many philosophers have rejected Benacerraf’s argument because it assumes a causal theory of knowledge, some maintain that Benacerraf nevertheless put his finger on a genuine problem, even though he didn’t state the problem in its most challenging form. After diagnosing what went wrong with Benacerraf’s argument, I argue that a new, more challenging, (...) version of Benacerraf’s problem can be constructed. The new version—what I call the Defeater Version—of Benacerraf’s problem makes use of a no-defeater condition on knowledge and justification. I conclude by arguing that the best way to avoid the problem is to construct a theory of how a priori judgments reliably track the facts. I also suggest four different kinds of theories worth pursuing. (shrink)

In his book, Disagreement, Deference, and Religious Commitment, John Pittard presents and critiques what he calls the “master argument for disagreement-motivated religious skepticism.” This argument purports to show, using only higher-order reasoning and facts about religious disagreement, that nobody’s religious outlook is justified (at least, nobody aware of the argument). The master argument presupposes that any attempt to vindicate one’s religious outlook must employ dispute-independent reasons. Pittard objects to this assumption and argues, instead, for rationalist weak conciliationism: the view that (...) partisan justification can be had when (and only when) one has rational insight into the claim in question. In this paper, I raise a challenge for rationalist weak conciliationism; in short, it is difficult to explain why only rational insight provides partisan justification while maintaining that a wide range of beliefs, including religious beliefs, can be justified in a partisan way. (shrink)

Most philosophers who have endorsed the idea that there is such a thing as phenomenal content—content that supervenes on phenomenal character—have also endorsed what I call Standard Russellianism. According to Standard Russellianism, phenomenal content is Russellian in nature, and the properties represented by perceptual experiences are mind-independent physical properties. In agreement with Sydney Shoemaker [Shoemaker, S. (1994). Philosophy and Phenomenological Research, 54 249–314], I argue that Standard Russellianism is incompatible with the possibility of spectrum inversion without illusion. One defense of (...) (...) Standard Russellianism is to hold that spectrum inversion without illusion is conceivable but not in fact possible. I argue that this response fails. As a consequence, either phenomenal content is not Russellian, or experiences do not represent mind-independent physical properties. (shrink)

W. V. Quine famously claimed that no statement is immune to revision. This thesis has had a profound impact on twentieth century philosophy, and it still occupies centre stage in many contemporary debates. However, despite its importance it is not clear how it should be interpreted. I show that the thesis is in fact ambiguous between three substantially different theses. I illustrate the importance of clarifying it by assessing its use in the debate against the existence of a priori knowledge. (...) I show how the three different readings of the thesis can be used to generate three substantially different and philosophically significant arguments against the a priori. I further challenge each one of these arguments against the a priori. (shrink)

Segundo um influente argumento contra a existência de conhecimento a priori, não há conhecimento a priori porque (i) nenhuma crença é imune à revisão, e (ii) se houvesse conhecimento a priori, algumas crenças seriam irrevisíveis. Uma versão deste argumento foi celebremente defendida por W. V. Quine e ainda é popular entre filósofos naturalistas. O objectivo deste artigo é examinar e rejeitar este argumento contra o a priori. O artigo começa por discutir a tese (i) e o seu papel no modelo (...) da Teia de Crenças de Quine. Defende-se que (i) enfrenta importantes desafios que colocam em risco o seu uso no argumento supra. A premissa (ii) do argumento é então discutida. Philip Kitcher é conhecido pela sua defesa de uma versão da premissa (ii). Os seus argumentos são analisados e rejeitados. A conclusão é que não temos uma boa razão para aceitar (ii), e consequentemente este argumento contra o a priori. O artigo termina com a proposta de uma caracterização do a priori perfeitamente compatível com (i). (shrink)

This paper aims to clarify a debate on philosophical method, and to give a probabilistic argument vindicating armchair philosophy under a wide range of plausible assumptions. The use of intuitions by so-called armchair philosophers has been criticized on empirical grounds. The debate between armchair philosophers and their empirical critics would benefit from greater clarity and precision in our understanding of what it takes for intuition-based approaches to philosophy to make sense. This paper discusses a set of rigorous, probability-based tools for (...) determining what we can and cannot learn from intuitions in various conditions. These tools can tell us whether beliefs can be justified by armchair practices, and what empirical findings would have to show to undermine the use of intuitions in philosophy. Using these tools, the paper shows that armchair philosophy makes sense in a broad range of situations, and that it is quite plausible that we are in those situations at the moment. (shrink)

One mainstream approach to philosophy involves trying to learn about philosophically interesting, non-mental phenomena—ethical properties, for example, or causation—by gathering data from human beings. I call this approach “wide tent traditionalism.” It is associated with the use of philosophers’ intuitions as data, the making of deductive arguments from this data, and the gathering of intuitions by eliciting reactions to often quite bizarre thought experiments. These methods have been criticized—I consider experimental philosophy’s call for a move away from the use of (...) philosophers’ intuitions as evidence, and recent suggestions about the use of inductive arguments in philosophy—and these criticisms point out important areas for improvement. However, embracing these reforms in turn gives wide-tent traditionalists strong reasons to maintain other traditional approaches to philosophy. Specifically, traditionalists’ commitment to using intuitions and to gathering them with bizarre thought experiments is well founded, both philosophically and empirically. I end by considering some problems with gathering trustworthy intuitions, and give suggestions about how best to solve them. (shrink)

The author uses a series of examples to illustrate two versions of a new, nonprobabilist principle of epistemic rationality, the special and general versions of the metacognitive, expected relative frequency principle. These are used to explain the rationality of revisions to an agent’s degrees of confidence in propositions based on evidence of the reliability or unreliability of the cognitive processes responsible for them—especially reductions in confidence assignments to propositions antecedently regarded as certain—including certainty-reductions to instances of the law of excluded (...) middle or the law of noncontradiction in logic or certainty-reductions to the certainties of probabilist epistemology. The author proposes special and general versions of the MERF principle and uses them to explain the examples, including the reasoning that would lead to thoroughgoing fallibilism—that is, to a state of being certain of nothing. The author responds to the main defenses of probabilism: Dutch Book arguments, Joyce’s potential accuracy defense, and the potential calibration defenses of Shimony and van Fraassen by showing that, even though they do not satisfy the probability axioms, degrees of belief that satisfy the MERF principle minimize expected inaccuracy in Joyce’s sense; they can be externally calibrated in Shimony and van Fraassen’s sense; and they can serve as a basis for rational betting, unlike probabilist degrees of belief, which, in many cases, human beings have no rational way of ascertaining. The author also uses the MERF principle to subsume the various epistemic akrasia principles in the literature. Finally, the author responds to Titelbaum’s argument that epistemic akrasia principles require that we be certain of some epistemological beliefs, if we are rational. (shrink)

The distinction between a priori and a posteriori knowledge has been the subject of an enormous amount of discussion, but the literature is biased against recognizing the intimate relationship between these forms of knowledge. For instance, it seems to be almost impossible to find a sample of pure a priori or a posteriori knowledge. In this paper, it will be suggested that distinguishing between a priori and a posteriori is more problematic than is often suggested, and that a priori and (...) a posteriori resources are in fact used in parallel. We will define this relationship between a priori and a posteriori knowledge as the bootstrapping relationship. As we will see, this relationship gives us reasons to seek for an altogether novel definition of a priori and a posteriori knowledge. Specifically, we will have to analyse the relationship between a priori knowledge and a priori reasoning , and it will be suggested that the latter serves as a more promising starting point for the analysis of aprioricity. We will also analyse a number of examples from the natural sciences and consider the role of a priori reasoning in these examples. The focus of this paper is the analysis of the concepts of a priori and a posteriori knowledge rather than the epistemic domain of a posteriori and a priori justification. (shrink)

In this paper I will offer a novel understanding of a priori knowledge. My claim is that the sharp distinction that is usually made between a priori and a posteriori knowledge is groundless. It will be argued that a plausible understanding of a priori and a posteriori knowledge has to acknowledge that they are in a constant bootstrapping relationship. It is also crucial that we distinguish between a priori propositions that hold in the actual world and merely possible, non-actual a (...) priori propositions, as we will see when considering cases like Euclidean geometry. Furthermore, contrary to what Kripke seems to suggest, a priori knowledge is intimately connected with metaphysical modality, indeed, grounded in it. The task of a priori reasoning, according to this account, is to delimit the space of metaphysically possible worlds in order for us to be able to determine what is actual. (shrink)

What I will call “the deviant logician objection” [DLO] is one line of attack against the common and compelling tenet that our justification for logical truths is grounded in our understanding of their constituent concepts. This objection seeks to undermine the possibility of any deep constitutive connection, in the epistemology of logic, between understanding and justification. I will consider varieties of the deviant logician objection developed by Horwich and by Williamson. My thesis is that while the deviant logician objection falls (...) short of proving that this traditional tenet must be rejected, nonetheless it serves to bolster some important refinements. (shrink)

Originally published in 1991, The Laboratory of the Mind: Thought Experiments in the Natural Sciences, is the first monograph to identify and address some of the many interesting questions that pertain to thought experiments. While the putative aim of the book is to explore the nature of thought experimental evidence, it has another important purpose which concerns the crucial role thought experiments play in Brown’s Platonic master argument.In that argument, Brown argues against naturalism and empiricism (Brown 2012), for mathematical Platonism (...) (Brown 2008), and from the Platonist-friendly, abstract universals posited by the Dretske-Tooley-Armstrong (DTA) account of the laws of nature to a more general, physical Platonism. The Laboratory of the Mind is where he takes this final step. (shrink)

BonJour has proposed background conditions on internalist justification, which Kornblith argues are inconsistent with a core internalist ‘credo’ – that subjects internally alike are justificationally alike – signaling the ‘death’ of internalism. The funeral arrangements are premature, though more systematic consideration of background conditions is needed. The majority of BonJour's conditions are not background conditions as their failure makes an epistemically relevant internal difference. This neutralizes Kornblith's criticisms and reveals how the proposed conditions are not departures from internalism. BonJour's background (...) conditions are simply conditions, the credo remains intact, and Kornblith's objections do not spell problems for internalism, let alone death. (shrink)

Does rationality require logical omniscience? Our best formal theories of rationality imply that it does, but our ordinary evaluations of rationality seem to suggest otherwise. This paper aims to resolve the tension by arguing that our ordinary evaluations of rationality are not only consistent with the thesis that rationality requires logical omniscience, but also provide a compelling rationale for accepting this thesis in the first place. This paper also defends an account of apriori justification for logical beliefs that is designed (...) to explain the rational requirement of logical omniscience. On this account, apriori justification for beliefs about logic has its source in logical facts, rather than psychological facts about experience, reasoning, or understanding. This account has important consequences for the epistemic role of experience in the logical domain. In a slogan, the epistemic role of experience in the apriori domain is not a justifying role, but rather an enabling and disabling role. (shrink)