In recent years many influential philosophers have advocated that philosophy is an a priori science. Yet very few epistemology textbooks discuss a priori knowledge at any length, focusing instead on empirical knowledge and empirical justification. As a priori knowledge has moved centre stage, the literature remains either too technical or too out of date to make up a reasonable component of an undergraduate course. Edwin Mares book aims to rectify this. This book seeks to make accessible to (...) students the standard topics and current debates within a priori knowledge, including necessity and certainty, rationalism, empiricism and analyticity, Quine's attack on the a priori, Kantianism, Aristotelianism, mathematical knowledge, moral knowledge, logical knowledge and philosophical knowledge. (shrink)

Kant's philosophy promises to explain various synthetic a priori claims. Yet, as several of his commentators have noted, it is hard to see how these explanations could work unless they themselves rested on unexplained synthetic a priori claims. Since Kant appears to demand explanations for all synthetic a priori claims, it would seem that his project fails on its own terms. I argue, however, that Kant holds that explanations are required only for synthetic a priori claims (...) about (purportedly) experience-independent entities, and that his project rests on a rationalist method of reflection that justifies certain basic synthetic a priori claims. (shrink)

The acquisition and evolution of speech production, discourse and communication can be negatively impacted by brain malformations. We describe, for the first time, a case of developmental dynamic dysphasia (DDD) in a right-handed adolescent boy (subject D) with cortical malformations involving language-eloquent regions (inferior frontal gyrus) in both the left and the right hemispheres. Language evaluation revealed a markedly reduced verbal output affecting phonemic and semantic fluency, phrase and sentence generation and verbal communication in everyday life. Auditory comprehension, repetition, naming, (...) reading and spelling were relatively preserved, but executive function was impaired. Multimodal neuroimaging showed a malformed cerebral cortex with atypical configuration and placement of white matter tracts bilaterally and abnormal callosal fibers. Dichotic listening showed right hemisphere dominance for language and functional magnetic resonance imaging (fMRI) additionally revealed dissociated hemispheric language representation with right frontal activation for phonology and bilateral dominance for semantic processing. Moreover, subject D also had congenital mirror movements (CMM), defined as involuntary movements of one side of the body that mirror intentional movements of the other side. Transcranial magnetic stimulation and fMRI during voluntary unimanual (left and right) hand movements showed bilateral motor cortex recruitment and tractography revealed a lack of decussation of bilateral corticospinal tracts. Genetic testing aimed to detect mutations that disrupt the development of commissural tracts correlating with CMM (e.g., Germline DCC mutations) was negative. Overall, our findings suggest that DDD in subject D resulted from the underdevelopment of the left inferior frontal gyrus with limited capacity for plastic reorganization by its homologous counterpart in the right hemisphere. Corpus callosum anomalies probably contributed to hinder interhemispheric connectivity necessary to compensate language and communication deficits after left frontal involvement. (shrink)

Neste artigo, primeiramente, apresento tese de Kripke sobre a possibilidade de se adquirir conhecimento de verdades contingentes a priori e a crítica de Keith Donnellan a essa tese. Depois, exploro a distinção que Donnellan faz entre (a) saber que uma sentença é verdadeira e (b) conhecer a verdade que essa sentença expressa. Argumento que essa distinção não é relevante apenas no contexto de sua crítica ao contingente a priori, mas sim para nossa prática com nomes próprios de modo (...) geral. Tento mostrar que conhecer o significado de nomes próprios não se resume à nossa competência linguística com eles, mas depende de termos acquaintance com seus portadores. Se isso é verdadeiro, então a tese do contingente a priori, tal como formulada por Kripke, não pode estar correta. (shrink)

The major divide in contemporary epistemology is between those who embrace and those who reject a priori knowledge. Albert Casullo provides a systematic treatment of the primary epistemological issues associated with the controversy. By freeing the a priori from traditional assumptions about the nature of knowledge and justification, he offers a novel approach to resolving these issues which assigns a prominent role to empirical evidence. He concludes by arguing that traditional approaches to the a priori, which focus (...) primarily on the concepts of necessity and analyticity, are misguided. (shrink)

The idea that the epistemology of modality is in some sense a priori is a popular one, but it has turned out to be difficult to precisify in a way that does not expose it to decisive counterexamples. The most common precisifications follow Kripke’s suggestion that cases of necessary a posteriori truth that can be known a priori to be necessary if true ‘may give a clue to a general characterization of a posteriori knowledge of necessary truths’. The (...) idea is that whether it is contingent whether p can be known a priori for at least some broad range of sentences ‘p’. Recently, Al Casullo and Jens Kipper have discussed restrictions of such principles to atomic sentences. We show that decisive counterexamples even to such dramatically restricted Kripke-style principles can be constructed using minimal logical resources. We then consider further restrictions, and show that the counterexamples to the original principles can be turned into counterexamples to the further restricted principles. We conclude that, if there are any true restrictions of Kripke-style principles, then they are so weak as to be of little epistemological interest. (shrink)

Many philosophers are again examining the traditional topic of a priori knowledge, or knowledge that does not depend on sensory experience. This volume collects the most important recent essays on the subject by well-known thinkers such as A.J. Ayer, W.V. Quine, Barry Stroud, C.I. Lewis, Hilary Putnam, Roderick M. Chisholm, Saul A. Kripke, Albert Casullo, R.G. Swinburne, and Philip Kitcher. Including an introduction by the editor and an extensive bibliography, this book provides philosophers and students with an in-depth look (...) at contemporary investigations into the nature of a priori knowledge. (shrink)

This dissertation is about a priori justification and its relationship to experiential evidence. I begin with the assumption that a priori justification is justification that is independent of experience. It has been argued that putative examples of a priori justification are implausible because they are not, in any significant sense, independent of experience. My two central claims are that (a) a subject is plausibly justified a priori in believing a proposition only if the belief is not (...) revisable on empirical grounds, which I will call the empirical unrevisability thesis; and (b) moderate rationalists can resist four empirical challenges considered by many to be decisive against the empirical unrevisability thesis. I begin by developing an account of experiential evidence that is neutral between rationalists and empiricists in order to make clear the distinction between a priori and a posteriori justification. I then argue that a moderate rationalist account of a priori justification is plausible only if the beliefs justified a priori are empirically unrevisable in a qualified sense. I then argue that four classical objections that putative cases of a priori justification are not independent of experience fail, namely, that they are revisable by some instances of contrary testimony, by mistakes in long proofs and memory, that a paradigm example of a priori knowledge was overturned by new evidence in physics, and that psychological data undermines the reliability of sources of a priori justification. I conclude that there is only one potentially threatening case, derived from neurological malfunction, and I leave the solution to this case to future research. (shrink)

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)

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)

This article discusses the role of a priori and a posteriori knowledge and methods in metaphysics and metametaphysics. Issues discussed include the viability of the distinction, the continuity of a priori and a posteriori methods, connections to modal epistemology, and the role of the distinction for science and naturalistic metaphysics.

The terms "a priori" and "a posteriori" refer primarily to how or on what basis a proposition might be known. A proposition is knowable a priori if it is knowable independently of experience. A proposition is knowable a posteriori if it is knowable on the basis of experience. The a priori/a posteriori distinction is epistemological and should not be confused with the metaphysical distinction between the necessary and the contingent or the semantical or logical distinction between the (...) analytic and the synthetic. Two aspects of the a priori/a posteriori distinction require clarification: the conception of experience on which the distinction turns; and the sense in which a priori knowledge is independent of such experience. The latter gives rise to important questions regarding the positive basis of a priori knowledge. (shrink)

In his recent book Constructing the World, David Chalmers defends A Priori Scrutability, the thesis that there is a compact class of truths such that for any truth p, a Laplacian intellect could know a priori that if the truths in that class hold, then p. In this paper, I develop an objection to Chalmers’ thesis that focuses on his treatment of a so-called that’s-all truth. My objection draws on Theodore Sider’s discussion of border-sensitive properties, and also on (...) the causal phenomenon of double prevention. (shrink)

a priori. Since I ended up defending an unpopular answer to this question—"No"—it’s hardly surprising that people have scrutinized the account, or that many have concluded that I stacked the deck in the first place. Of course, this was not my view of the matter. My own judgment was that I’d uncovered the tacit commitments of mathematical apriorists and that the widespread acceptance of mathematical apriorism rested on failure to ask what was needed for knowledge to be a (...) class='Hi'>priori . Nevertheless, my critics have raised important challenges, and have offered rival conceptions that are less demanding. I want to examine their objections to my explication of a priori knowledge, and to explore whether the weaker alternatives succeed in preserving traditional philosophical claims. What follows is a mixture of penitence and intransigence. (shrink)

Sober and Elgin defend the claim that there are a priori causal laws in biology. Lange and Rosenberg take issue with this on Humean grounds, among others. I will argue that Sober and Elgin don’t go far enough – there are a priori causal laws in many sciences. Furthermore, I will argue that this thesis is compatible with a Humean metaphysics and an empiricist epistemology.

The book records a series of philosophical exchanges between its authors, amounting to a debate extended over more than fifteen years. Its subject matter is the nature and scope of reason. A central case at issue is basic logical knowledge, and the justification for basic deductive inferences, but the arguments range far more widely, at stake the distinctions between analytic and synthetic, and between a priori and a posteriori. The discussion naturally involves problems about the conditions for linguistic understanding (...) and competence, and what it might be to grasp a concept or to have an intuition. Since reason is central to philosophical method, there are associated implications for how philosophy itself works, or should work. In particular, the discussion raises fundamental concerns about how to approach epistemology. -/- . (shrink)

In this article I investigate a neglected form of radical skepticism that questions whether any of our logical, mathematical and other seemingly self-evident beliefs count as knowledge. ‘A priori skepticism,’ as I will call it, challenges our ability to know any of the following sorts of propositions: (1.1) The sum of two and three is five. (1.2) Whatever is square is rectangular. (1.3) Whatever is red is colored. (1.4) No surface can be uniformly red and uniformly blue at the (...) same time. (1.5) If ‘if p then q’ is true and ‘p’ is true, then ‘q’ is true. (1.6) No statement can be both true and false at the same time and in the same respect. (1.7) If A is taller than B, and B is taller than C, then A is taller than C. (1.8) Everything is identical to itself. (1.9) If the conclusion of an inductive argument is contingent, it is possible for the premises of that argument to be true and its conclusion to be false. (1.10) George W. Bush could have been a plumber. (1.11) George W. Bush could not have been a prime number. (1.12) ‘2 + 3 = 5’ is necessarily true. (shrink)

The primary aim of this chapter is to evaluate whether considerations about a priori domains and abstract objects favor atheism over theism.

I examine how Kant argues for the transcendental ideality of space. I defend a reading on which Kant accepts the ideality of space because it explains our (actual) knowledge that mathematical judgments are necessarily true. I argue that this reading is preferable over the alternative suggestion that Kant can infer the ideality of space directly from the fact that we have an a priori intuition of space. Moreover, I argue that the reading I propose does not commit Kant to (...) incoherent modal views. If we carefully distinguish between different senses of modality, the fact that our spatial form of intuition is (in some sense) contingent does not undermine the claim that this form can explain how our mathematical judgments are (in some sense) necessary. (shrink)

In this paper I argue for a priori conjectural scientific knowledge about the world. Physics persistently only accepts unified theories, even though endlessly many empirically more successful disunified rivals are always available. This persistent preference for unified theories, against empirical considerations, means that physics makes a substantial, persistent metaphysical assumption, to the effect that the universe has a (more or less) unified dynamic structure. In order to clarify what this assumption amounts to, I solve the problem of what it (...) means to say of a theory that it is unified. There are, I argue, eight different kinds of unity important in theoretical physics, all varieties of one basic idea. This provides us with a precise way of partially ordering physical theories with respect to their degree of unity. It also leads to a hierarchical view of physics, according to which physics makes a number of increasingly insubstantial metaphysical assumptions concerning the comprehensibility and knowability of the universe. Two of these are identified as constituting a priori conjectures. I conclude by arguing that the view developed in the paper resolves the traditional clash between empiricism and rationalism in the philosophy of science, and has important implications for science, and for academic inquiry more generally. (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.

Broadly speaking, a naturalistic approach to epistemology seeks to explain human knowledge – and justification in particular – as a phenomenon in the natural world, in keeping with the tenets of naturalism. Naturalism is typically defined, in part, by a commitment to scientific method as the only legitimate means of attaining knowledge of the natural world. Naturalism is often thought to entail empiricism by virtue of this methodological commitment. However, scientific methods themselves may incorporate a priori elements, so empiricism (...) does not follow from the methodological commitments of naturalism alone. And given a suitably-naturalistic conception of the a priori, a priori forms of justification may be compatible with naturalism generally. A priori justification is, in principle, compatible with naturalism – and hence naturalistic epistemologies – if the a priori is understood in a way that is free of some of the inessential properties that have been associated with the concept. I argue that some of the more prominent strategies for accommodating normative notions within a naturalistic framework allow for the possibility of a priori justification. These include reliabilism, instrumental rationality, and nonfactualism about justification. A priori justification thus need not be seen as standing in opposition to all naturalistic epistemologies. It is only with nonnormative naturalistic epistemologies that a priori justification per se is incompatible, and this only because the notion of justification itself has no role to play within a nonnormative approach to epistemology. (shrink)

One strategy for blocking Chalmers's overall case against physicalism has been to deny his claim that showing that phenomenal properties are in some sense physical requires an a priori entailment of the phenomenal truths from the physical ones. Here I avoid this well-trodden ground and argue instead that an a priori entailment of the phenomenal truths from the physical ones does not require an analysis in the Jackson/Chalmers sense. This is to sever the dualist's link between conceptual analysis (...) and a priori entailment by showing that the lack of the former does not imply the absence of the latter. Moreover, given the role of the argument from conceptual analysis in Chalmers's overall case for dualism, undermining that argument effectively undermines that case as a whole in a way that, I'll argue, undermining the conceivability arguments as stand-alone arguments does not. (shrink)

Hegel’s many remarks that seem to imply that philosophy should proceed completely a priori pose a problem for his philosophy of nature since, on this reading, Hegel offers an a priori derivation of...

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)

Colin McGinn; XI*—A priori and a posteriori Knowledge, Proceedings of the Aristotelian Society, Volume 76, Issue 1, 1 June 1976, Pages 195–208, https://doi.org/.

This is the second in a two part series of articles that attempt to clarify the nature and enduring relevance of Kant's concept of a priori knowledge. (For Part I, see below.) In this article I focus mainly on Saul Kripke's critique of Kant, in Naming and Necessity. I argue that Kripke draws attention to a genuine defect in Kant's epistemological framework, but that he used definitions of certain key terms that were quite different from Kant's definitions. When Kripke's (...) definitions are replaced by Kant's definitions, Kripke's account of the status of naming turns out to be a defense of analytic aposteriority as a significant classification of knowledge that Kant neglected. I also introduce here a new way of understanding such epistemological labels, as defining the perspective adopted by the knowing subject in a given situation, rather than an objective characteristic of certain propositions as such. (shrink)

This paper argues there are crucial points in Nietzsche’s texts where he offers a priori epistemic justification for views he believes are correct. My reading contrasts with the dominant view that Nietzsche’s philosophical naturalism is incompatible with a priori justification. My aim is to develop Nietzsche’s brand of a priori justification, show that he employs this account of justification in the texts, and suggest how it might be compatible with naturalism.

To evaluate Hume's thesis that causal claims are always empirical, I consider three kinds of causal statement: ?e1 caused e2 ?, ?e1 promoted e2 ?, and ?e1 would promote e2 ?. Restricting my attention to cases in which ?e1 occurred? and ?e2 occurred? are both empirical, I argue that Hume was right about the first two, but wrong about the third. Standard causal models of natural selection that have this third form are a priori mathematical truths. Some are obvious, (...) others less so. Empirical work on natural selection takes the form of defending causal claims of the first two types. I provide biological examples that illustrate differences among these three kinds of causal claim. (shrink)

This book answers three questions: (i) What is it for a statement to be analytically true? (ii) What is a priori knowledge? (How does it differ from inherited empirical knowledge? And how does it differ from acquired conceptual (non-empirical) knowledge, such as one's knowledge that not all continuous functions are differentiable?). (iii) Do we have a priori knowledge? It is shown that content-externalism is an 'epistemologicization' of the (logically, not psychologically) innocuous fact that, if a sentence S of (...) natural language expresses a multiply quantified generalization, S also expresses each quantified generalization obtained by permuting the quantifiers in it. It is also shown that, through judicious usage of Kaplan's dthat-operator, the shred of truth in content externalism can be reconciled with the datum that, in virtue of having a given representational content R, a mental state M has causal powers that it would not otherwise have. And it is thereby shown how to reconcile content-externalism, so far as the latter is true, with the legitimacy of individualist approaches to psychology. Finally, it is shown that content-externalism embodies a crude and false conception of the nature of the relationship between the literal meanings of linguistic expressions, on the one hand, and, on the other hand, the contents of the thoughts underlying our usage of such expressions. More precisely, content-externalism presupposes that literal meaning and cognitive content are in lockstep with each other; which, it is shown, is not the case and---what is also shown---only appears to be the case because of a failure on the part of semanticists to know where to draw the line between semantics and pragmatics. (shrink)

Philosophers love a priori knowledge: we delight in truths that can be known from the comfort of our armchairs, without the need to venture out in the world for confirmation. This is due not to laziness, but to two different considerations. First, it seems that many philosophical issues aren’t settled by our experience of the world — the nature of morality; the way concepts pick out objects; the structure of our experience of the world in which we find ourselves (...) — these issues seem to be decided not on the basis of our experience, but in some manner by things prior to (or independently of) that experience. Second, even when we are deeply interested in how our experience lends credence to our claims about the world, the matter remains of the remainder: we learn more about how experience contributes to knowledge when we see what knowledge is available independent of that experience. (shrink)

Robert Hanna works out a unified contemporary Kantian theory of rational human cognition and knowledge. Along the way, he provides accounts of intentionality and its contents, sense perception and perceptual knowledge, the analytic-synthetic distinction, the nature of logic, and a priori truth and knowledge in mathematics, logic, and philosophy. This book is specifically intended to reach out to two very different audiences: contemporary analytic philosophers of mind and knowledge, and contemporary Kantian philosophers or Kant-scholars. At the same time, it (...) rides the crest of a wave of exciting and revolutionary emerging new trends and new work in the philosophy of mind and epistemology, with a special concentration on the philosophy of perception. What is revolutionary in this new wave are its strong emphases on action, on cognitive phenomenology, on disjunctivist direct realism, on embodiment, and on sense perception as a primitive and proto-rational capacity for cognizing the world. Hanna makes a fundamental contribution to this philosophical revolution by giving it a specifically contemporary Kantian twist, and by pushing these new lines of investigation radically further. (shrink)

This paper argues for and explores the implications of the following epistemological principle for knowability a priori (with 'Ka' abbreviating 'it is knowable a priori that'). -/- (AK) For all ϕ, ψ such that ϕ semantically presupposes ψ: if Ka(ϕ), Ka(ψ). -/- Well-known arguments for the contingent a priori and a priori knowledge of logical truth founder when the semantic presuppositions of the putative items of knowledge are made explicit. Likewise, certain kinds of analytic truth turn (...) out to carry semantic presuppositions that make them ineligible as items of a priori knowledge. -/- On a happier note, I argue that (AK) offers an appealing, theory-neutral explanation of the a posteriori character of certain necessary identities, as well as an interesting rationalization for a commonplace linguistic maneuver in philosophical work on the a priori. (shrink)

La question du synthétique a priori définie par Husserl, malgré la critique adressée par le Cercle de Vienne, est réouverte. Plutôt que de fonder le concept à partir de l'intuition, l'auteur propose de le fonder à partir du concept. Il s'appuie sur la pensée de Bolzano, pour en faire le principe d'une lecture de Kant, Husserl, Schlick et Wittgenstein.