Does G. E. Moore know that he has hands? Yes, says the dogmatist: Moore’s hands are right before his eyes. No, says the skeptic: for all Moore knows he could be a brain-in-a-vat. Yes and no, says the contrastivist: yes, Moore knows that he has hands rather than stumps; but no, Moore does not know that he has hands rather than vat-images of hands. The dogmatist and the skeptic suppose that knowledge is a binary, categorical relation: s knows that p. (...) The contrastivist says that knowledge is a ternary, contrastive relation: s knows that p rather than q. (shrink)

Epistemic Angst offers a completely new solution to the ancient philosophical problem of radical skepticism—the challenge of explaining how it is possible to have knowledge of a world external to us. Duncan Pritchard argues that the key to resolving this puzzle is to realize that it is composed of two logically distinct problems, each requiring its own solution. He then puts forward solutions to both problems. To that end, he offers a new reading of Wittgenstein's account of the structure of (...) rational evaluation and demonstrates how this provides an elegant solution to one aspect of the skeptical problem. Pritchard also revisits the epistemological disjunctivist proposal that he developed in previous work and shows how it can effectively handle the other aspect of the problem. Finally, he argues that these two antiskeptical positions, while superficially in tension with each other, are not only compatible but also mutually supporting. The result is a comprehensive and distinctive resolution to the problem of radical skepticism, one that challenges many assumptions in contemporary epistemology. (shrink)

In Unnatural Doubts, Michael Williams constructs a masterly polemic against the very idea of epistemology, as traditionally conceived.

How should the contrastivist formulate closure? That is, given that knowledge is a ternary contrastive state Kspq (s knows that p rather than q), how does this state extend under entailment? In what follows, I will identify adequacy conditions for closure, criticize the extant invariantist and contextualist closure schemas, and provide a contrastive schema based on the idea of extending answers. I will conclude that only the contrastivist can adequately formulate closure.

Consider the skeptic about the external world. Let’s straightaway concede to such a skeptic that perception gives us no conclusive or certain knowledge about our surroundings. Our perceptual justification for beliefs about our surroundings is always defeasible—there are always possible improvements in our epistemic state which would no longer support those beliefs. Let’s also concede to the skeptic that it’s metaphysically possible for us to have all the experiences we’re now having while all those experiences are false. Some philosophers dispute (...) this, but I do not. The skeptic I want to consider goes beyond these familiar points to the much more radical conclusion that our perceptual experiences can’t give us any knowledge or even justification for believing that our surroundings are one way rather than another. (shrink)

This paper examines the relationship between perceptual knowledge and discrimination in the light of the so-called ‘relevant alternatives’ intuition. It begins by outlining an intuitive relevant alternatives account of perceptual knowledge which incorporates the insight that there is a close connection between perceptual knowledge and the possession of relevant discriminatory abilities. It is argued, however, that in order to resolve certain problems that face this view, it is essential to recognise an important distinction between favouring and discriminating epistemic support that (...) is often overlooked in the literature. This distinction complicates the story regarding how an alternative becomes relevant, and in doing so weakens the connection between perceptual knowledge and discrimination. The theory that results, however—what I term a ‘two-tiered’ relevant alternatives theory of perceptual knowledge—accommodates many of our intuitions about perceptual knowledge and so avoids the revisionism of some recent proposals in the epistemological literature. (shrink)

Support is canvassed for a novel solution to the sceptical problem regarding our knowledge of the external world. Key to this solution is the claim that what initially looks like a single problem is in fact two logically distinct problems. In particular, there are two putative sceptical paradoxes in play here, which each trade on distinctive epistemological theses. It is argued that the ideal solution to radical scepticism would thus be a biscopic proposal—viz., a two-pronged, integrated, undercutting treatment of both (...) putative sceptical paradoxes. A particular biscopic proposal is then explored which brings together two apparently opposing anti-sceptical theses: he Wittgensteinian account of the structure of rational evaluation and epistemological disjunctivism. It is argued that each proposal enables us to gain a purchase on one, but only one, aspect of the two-sided sceptical problem. Furthermore, it is argued that these proposals are not only compatible positions, but also mutually supporting and advanced in the same undercutting spirit. A potential cure is thus offered for epistemic angst. (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.

Knowledge and Lotteries is organized around an epistemological puzzle: in many cases, we seem consistently inclined to deny that we know a certain class of propositions, while crediting ourselves with knowledge of propositions that imply them. In its starkest form, the puzzle is this: we do not think we know that a given lottery ticket will be a loser, yet we normally count ourselves as knowing all sorts of ordinary things that entail that its holder will not suddenly acquire a (...) large fortune. After providing a number of specific and general characterizations of the puzzle, Hawthorne carefully examines the competing merits of candidate solutions. In so doing, he explores a number of central questions concerning the nature and importance of knowledge, including the relationship of knowledge to assertion and practical reasoning, the status of epistemic closure principles, the merits of various brands of scepticism, the prospects for a contextualist account of knowledge, and the potential for other sorts of salience-sensitive accounts. Along the way, he offers a careful treatment of pertinent issues at the foundations of semantics. His book will be of interest to anyone working in the field of epistemology, as well as to philosophers of language. (shrink)

This paper presents a partial analysis of perceptual knowledge, an analysis that will, I hope, lay a foundation for a general theory of knowing. Like an earlier theory I proposed, the envisaged theory would seek to explicate the concept of knowledge by reference to the causal processes that produce (or sustain) belief. Unlike the earlier theory, however, it would abandon the requirement that a knower's belief that p be causally connected with the fact, or state of affairs, that p.

In the good old days, a large part of the debate about skepticism focused on the quality of the reasons we have for believing propositions of various types. Skeptics about knowledge in a given domain argued that our reasons for believing propositions in that domain were not good enough to give us knowledge; opponents of skepticism argued that they were. The different conclusions drawn by skeptics and non-skeptics could come either from differences in their views about the standards or conditions (...) we had to satisfy in order to have knowledge or from differences in their assessments of the quality or character of the reasons we have. In recent years, discussions of skepticism have often focused on three anti-skeptical responses that don't directly address the questions about reasons or evidence that used to be considered fundamental. These anti-skeptical responses are: 1) content externalism, as proposed by Hilary Putnam1; 2) the denial of closure, as proposed by Robert Nozick2; and 3) contextualism about knowledge attributions, as proposed by Stewart Cohen, Keith DeRose, and David Lewis3. I believe that these recent responses to skepticism characteristically avoid the central epistemological issues raised by skepticism and often concede to skeptics far more than is warranted. In this paper I will examine some contextualist responses to skepticism. In Section I I describe the general idea of contextualism and its application to skepticism. In Section II I describe and briefly discuss some particular versions of contextualism. In Section III I argue that even if it is true that sentences attributing knowledge have contextually variable truth conditions, this fact does not provide the basis for a satisfactory response to skepticism. This is because the central issue raised by skepticism is whether we satisfy the standards for knowledge in place in ordinary contexts, not whether we satisfy some allegedly higher standards which, according to contextualists, are in place in some epistemological contexts. In effect, this paper is part of an argument for a return to the good old days. (shrink)

Nozick analyzes fundamental issues, such as the identity of the self, knowledge and skepticism, free will, the foundations of ethics, and the meaning of life.

Epistemological disjunctivism in outline -- Favouring versus discriminating epistemic support -- Radical scepticsim.

Much philosophy of logic is shaped, explicitly or implicitly, by the thought that logic is distinctively formal and abstracts from material content. The distinction between formal and material does not appear to coincide with the more familiar contrasts between a priori and empirical, necessary and contingent, analytic and synthetic—indeed, it is often invoked to explain these. Nor, it turns out, can it be explained by appeal to schematic inference patterns, syntactic rules, or grammar. What does it mean, then, to say (...) that logic is distinctively formal? (shrink)