In this paper I argue for a doctrine I call ?infallibilism?, which I stipulate to mean that If S knows that p, then the epistemic probability of p for S is 1. Some fallibilists will claim that this doctrine should be rejected because it leads to scepticism. Though it's not obvious that infallibilism does lead to scepticism, I argue that we should be willing to accept it even if it does. Infallibilism should be preferred because it has greater explanatory power (...) than fallibilism. In particular, I argue that an infallibilist can easily explain why assertions of ?p, but possibly not-p? (where the ?possibly? is read as referring to epistemic possibility) is infelicitous in terms of the knowledge rule of assertion. But a fallibilist cannot. Furthermore, an infallibilist can explain the infelicity of utterances of ?p, but I don't know that p? and ?p might be true, but I'm not willing to say that for all I know, p is true?, and why when a speaker thinks p is epistemically possible for her, she will agree (if asked) that for all she knows, p is true. The simplest explanation of these facts entails infallibilism. Fallibilists have tried and failed to explain the infelicity of ?p, but I don't know that p?, but have not even attempted to explain the last two facts. I close by considering two facts that seem to pose a problem for infallibilism, and argue that they don't. (shrink)

Introduction -- Fallibilism -- Contextualism -- Knowledge and reasons -- Justification -- Belief -- The value and importance of knowledge -- Infallibilism or pragmatic encroachment? -- Appendix I: Conflicts with bayesian decision theory? -- Appendix II: Does KJ entail infallibilism?

Jason Stanley presents a startling and provocative claim about knowledge: that whether or not someone knows a proposition at a given time is in part determined by his or her practical interests, i.e. by how much is at stake for that person at that time. In defending this thesis, Stanley introduces readers to a number of strategies for resolving philosophical paradox, making the book essential not just for specialists in epistemology but for all philosophers interested in philosophical methodology. Since a (...) number of his strategies appeal to linguistic evidence, it will be of great interest to linguists as well. (shrink)

§I schematises the evidence for an understanding of ‘know’ and other terms of epistemic appraisal that embodies contextualism or subject-sensitive invariantism, and distinguishes between those two approaches. §II argues that although the cases for contextualism and sensitive invariantism rely on a principle of charity in the interpretation of epistemic claims, neither approach satisfies charity fully, since both attribute metalinguistic errors to speakers. §III provides an equally charitable anti-sceptical insensitive invariantist explanation of much of the same evidence as the result of (...) psychological bias caused by salience effects. §IV suggests that the explanation appears to have implausible consequences about practical reasoning, but also that applications of contextualism or sensitive invariantism to the problem of scepticism have such consequences. §V argues that the inevitable difference between appropriateness and knowledge of appropriateness in practical reasoning, closely related to the difference between knowledge and knowledge of knowledge, explains the apparent implausibility. (shrink)

David Lewis (1941-2001) was Class of 1943 University Professor of Philosophy at Princeton University. His contributions spanned philosophical logic, philosophy of language, philosophy of mind, philosophy of science, metaphysics, and epistemology. In On the Plurality of Worlds, he defended his challenging metaphysical position, "modal realism." He was also the author of the books Convention, Counterfactuals, Parts of Classes, and several volumes of collected papers.

Even though the lines of thought that support skepticism are extremely compelling, we're inclined to look for ways of blocking them because it appears to be an impossible view to accept, both for intellectual and practical reasons. One goal of this paper is to show that when skepticism is packaged right, it has few problematic implications (or at least fewer than is often assumed). It is, for example, compatible with all the following claims (when these are correctly interpreted).

Epistemologists generally agree that the stringency of intuitive ascriptions of knowledge is increased when unrealized possibilities ofenor are mentioned. Non-sceptical invanantists (Williamson, Hawthorne) think it a mistake to yield in such cases to the temptation to be more stringent, but they do not deny that we feel it. They contend that the temptation is best explained as the product of a psychological bias known as the availability heuristic. I argue against the availability explanation, and sketch a rival account of what (...) happens to us psychologically when possibilities of error are raised. (shrink)

I stipulate and motivate the overlooked problem of demarcating radical skeptics (perceptual and moral) from mentally disordered persons, given that both deny that they know ordinary Moorean propositions (e.g., that they have hands or that killing for fun is morally wrong). Call this ‘the demarcation problem’. In response to the demarcation problem, I develop a novel way to demarcate between mentally disordered persons and radical skeptics in an extensionally adequate way that saves the appearance that radical skeptics are not mentally (...) disordered persons (at least not typically). Finally, I examine how a Moorean, non-skeptical epistemologist would compare radical skeptics with the mentally disordered in terms of what Plantinga calls internal and external rationality. Perhaps surprisingly, by Moorean lights, the mentally disordered fare better than the radical skeptic in terms of (internal) rationality. The upshot is that for Mooreans skeptical philosophy is more of an epistemic evil than mental disorder. (shrink)

I present a cumulative case for the thesis that we only know propositions that are certain for us. I argue that this thesis can easily explain the truth of eight plausible claims about knowledge: -/- (1) There is a qualitative difference between knowledge and non-knowledge. (2) Knowledge is valuable in a way that non-knowledge is not. (3) Subjects in Gettier cases do not have knowledge. (4) If S knows that P, P is part of S’s evidence. (5) If S knows (...) that P, ~P is epistemically impossible for S. (6) If S knows that P, S can rationally act as if P. (7) If S knows that P, S can rationally stop inquiring whether P. (8) If S knows each of {P1, P2, … Pn}, and competently deduces Q from these propositions, S knows that Q. -/- I then argue that the skeptical costs of this thesis are outweighed by its explanatory power. (shrink)

This book contains twelve chapters by leading and up-and-coming philosophers on metaepistemology, that is, on the nature, existence and authority of epistemic facts. One of the central divides in metaepistemology is between epistemic realists and epistemic anti-realists. Epistemic realists think that epistemic facts exist independently of human judgements and practices, and that they have authority over our judgements and practices. Epistemic anti-realists think that, if epistemic facts exist at all, they are grounded in human judgements and practices, and gain any (...) authority they have from our judgements and practices. This book considers both epistemic realist and anti-realist perspectives, as well as perspectives that 'transcend' the realism/anti-realism dichotomy. As such, it constitutes the 'state of the art' with regard to metaepistemology, and will shape the debate in years to come. (shrink)

Expressivism is a blossoming meta-semantic framework sometimes relying on what Carter and Chrisman call “the core expressivist maneuver.” That is, instead of asking about the nature of a certain kind of value, we should be asking about the nature of the value judgment in question. According to expressivists, this question substitution opens theoretical space for the elegant, economical, and explanatorily powerful expressivist treatment of the relevant domain. I argue, however, that experimental work in cognitive psychology can shed light on how (...) the core expressivist maneuver operates at the cognitive level and that this: raises worries about the aptness of the expressivist question substitution and supports an evolutionary debunking argument against expressivism. Since evolutionary debunking arguments are usually run in favor of expressivism, this creates an obvious puzzle for expressivists. I wrap up by briefly responding to the objection that the debunking argument against expressivism overgeneralizes and, therefore, should be rejected. (shrink)

When spelled out properly infallibilism is a viable and even attractive view. Because it has long been summary dismissed, however, we need a guide on how to properly spell it out. The guide has to fulfil four tasks. The first two concern the nature of knowledge: to argue that infallible belief is necessary, and that it is sufficient, for knowledge. The other two concern the norm of belief: to argue that knowledge is necessary, and that it is sufficient, for justified (...) certainty. With such a guide in hand infallibilism can be evaluated on its own merits. The most controversial parts are the first and fourth. The idea that knowledge requires infallible belief is thought to be excessively sceptical. The idea that knowledge warrants certainty is thought to be excessively dogmatic. The present paper addresses the first. It argues that knowledge requires infallible belief. (shrink)

I present an argument for a sophisticated version of sceptical invariantism that has so far gone unnoticed: Bifurcated Sceptical Invariantism (BSI). I argue that it can, on the one hand, (dis)solve the Gettier problem, address the dogmatism paradox and, on the other hand, show some due respect to the Moorean methodological incentive of ‘saving epistemic appearances’. A fortiori, BSI promises to reap some other important explanatory fruit that I go on to adduce (e.g. account for concessive knowledge attributions). BSI can (...) achieve this much because it distinguishes between two distinct but closely interrelated (sub)concepts of (propositional) knowledge, fallible-but-safe knowledge and infallible-and-sensitive knowledge, and explains how the pragmatics and the semantics of knowledge discourse operate at the interface of these two (sub)concepts of knowledge. I conclude that BSI is a novel theory of knowledge discourse that merits serious investigation. (shrink)

There is abundant evidence of contextual variation in the use of “S knows p.” Contextualist theories explain this variation in terms of semantic hypotheses that refer to standards of justification determined by “practical” features of either the subject’s context (Hawthorne & Stanley) or the ascriber’s context (Lewis, Cohen, & DeRose). There is extensive linguistic counterevidence to both forms. I maintain that the contextual variation of knowledge claims is better explained by common pragmatic factors. I show here that one is variable (...) strictness. “S knows p” is commonly used loosely to implicate “S is close enough to knowing p for contextually indicated purposes.” A pragmatic account may use a range of semantics, even contextualist. I use an invariant semantics on which knowledge requires complete justification. This combination meets the Moorean constraint as well as any linguistic theory should, and meets the intuition constraint much better than contextualism. There is no need for ad hoc error theories. The variation in conditions of assertability and practical rationality is better explained by variably strict constraints. It will follow that “S knows p” is used loosely to implicate that the condition for asserting “p” and using it in practical reasoning are satisfied. (shrink)

A Moorean fact, in the words of the late David Lewis, is ‘one of those things that we know better than we know the premises of any philosophical argument to the contrary’. Lewis opens his seminal paper ‘Elusive Knowledge’ with the following declaration.

The skeptic says that “knowledge” is an absolute term, whereas the contextualist says that ‘knowledge” is a relationally absolute term. Which is the better hypothesis about “knowledge”? And what implications do these hypotheses about “knowledge” have for knowledge? I argue that the skeptic has the better hypothesis about “knowledge”, but that both hypotheses about “knowledge” have deeply anti‐skeptical implications for knowledge, since both presuppose our capacity for epistemically salient discrimination.

In this book, Henrik Lagerlund offers students, researchers, and advanced general readers the first complete history of what is perhaps the most famous of all philosophical problems: skepticism. As the first of its kind, the book traces the influence of philosophical skepticism from its roots in the Hellenistic schools of Phyrronism and the Middle Academy up to its impact inside and outside of philosophy today. Along the way, it covers skepticism during the Latin, Arabic, and Greek Middle Ages and during (...) the Renaissance before moving on to cover Descartes's methodological skepticism and Pierre Bayle's super-skepticism in the seventeenth century. In the eighteenth century, it deals with Humean skepticism and the anti-skepticism of Reid and Kant, taking care to also include reflections on the connections between idealism and skepticism. The book covers similar themes in a chapter on G.E. Moore and Ludwig Wittgenstein, and then ends its historical overview with a chapter on skepticism in contemporary philosophy. In the final chapter, Lagerlund captures some of skepticism's impact outside of philosophy, highlighting its relation to issues like the replication crisis in science and knowledge resistance. (shrink)

Do you know you are not being massively deceived by an evil demon? That is a familiar skeptical challenge. Less familiar is this question: How do you have a conception of knowledge on which the evil demon constitutes a prima facie challenge? Recently several philosophers have suggested that our responses to skeptical scenarios can be explained in terms of heuristics and biases. We offer an alternative explanation, based in learning theory. We argue that, given the evidence available to the learner, (...) it would be rational for the learner to infer an infallibilist conception of knowledge. (shrink)

Skeptical invariantism does not account for the intuitive connections between knowledge, assertion, and practical reasoning and this constitutes a significant problem for the position because it does not save corresponding epistemic appearances (cf. Hawthorne (2004:131-5)). Moreover, it is an attraction of fallibilist over infallibilist-skeptical views that they can easily account for the epistemic appearances about the connections between knowledge, assertion, and practical reasoning (cf. Williamson (2000:249-255)). Call this argument ‘the argument from the knowledge norm’. I motivate and develop a Humean, (...) pragmatist strategy for a skeptical response to ‘the argument from the knowledge norm’. Afterwards I outline a ‘toy’ version of pragmatic skepticism that can implement the strategy and save our everyday practice of assertion and practical reasoning. To this effect, I distinguish between assertibility conditions and truth conditions for ‘know’ and suggest that while assertibility conditions are pragmatic conditions sensitive to practical exigencies, truth conditions are semantic conditions sensitive only to truth. I briefly respond to three objections and conclude that pragmatic skepticism is resourceful enough to save our everyday practice of (fallibilist) assertion and practical reasoning and, hence, pay some due respect to corresponding epistemic appearances. (shrink)

Strict moderate invariantism is the ho-hum, ‘obvious’ view about knowledge attributions. It says knowledge attributions are often true and that only traditional epistemic factors like belief, truth, and justification make them true. As commonsensical as strict moderate invariantism is, it is equally natural to withdraw a knowledge attribution when error possibilities are made salient. If strict moderate invariantism is true, these knowledge-denials are often false because the subject does in fact know the proposition. I argue that strict moderate invariantism needs (...) an explanation of this phenomenon, but it does not have one. That is significant, for if strict moderate invariantism does not square with ordinary intuition, then it cannot rely on ordinary intuition for support. Section 1 introduces the concept of epistemic relevance blindness, which says ordinary subjects are generally insensitive to whether or not error possibilities are relevant to knowledge attributions. Section 2 focuses on Patrick Rysiew’s influential strict moderate invariantist pragmatic explanation of knowledge-denials and argues that such pragmatic explanations of knowledge-denials depend on attributors being epistemic relevance blind. Section 3 targets psychological explanations of epistemic relevance blindness offered separately by Jennifer Nagel and Mikkel Gerken. I argue that strict moderate invariantists lack a plausible explanation of epistemic relevance blindness. (shrink)

A sensible epistemologist may not see how she could know that she is not a brain in a vat ; but she doesn’t panic. She sticks with her empirical beliefs, and as that requires, believes that she is not a BIV. (She does not inferentially base her belief that she is not a BIV on her empirical knowledge—she rejects that ‘Moorean’ response to skepticism.) Drawing on the psychological literature on metacognition, I describe a mechanism that’s plausibly responsible for a sensible (...) epistemologist coming to believe she is not a BIV. I propose she thereby knows that she is not a BIV. The particular belief-forming mechanism employed explains why she overlooks this account of how she knows she is not a BIV, making it seem that there is no way for her to know it. I argue this proposal satisfactorily resolves the skeptical puzzle. (shrink)

In part one I present a positive argument for the claim that philosophical argument can rationally overturn common sense. It is widely agreed that science can overturn common sense. But every scientific argument, I argue, relies on philosophical assumptions. If the scientific argument succeeds, then its philosophical assumptions must be more worthy of belief than the common sense proposition under attack. But this means there could be a philosophical argument against common sense, each of whose premises is just as worthy (...) of belief as the scientist’s philosophical assumptions. If so, then the purely philosophical argument will also succeed. In part two I consider three motivations, each of which comprises a distinct philosophical methodology, for the opposing view: the Moorean idea that common sense enjoys greater plausibility than philosophy; case judgments should trump general principles; reflective equilibrium and conservatism. I argue that all three motivations fail. (shrink)

The main themes of the book are introduced in a preliminary and intuitive way.