This book, first published in 2000, is about the nature of skeptical arguments and their role in philosophical inquiry. John Greco delineates three main theses: that a number of historically prominent skeptical arguments make no obvious mistake, and therefore cannot be easily dismissed; that the analysis of skeptical arguments is philosophically useful and important, and should therefore have a central place in the methodology of philosophy; and that taking skeptical arguments seriously requires us to adopt an externalist, reliabilist epistemology. Greco (...) argues that the importance of skeptical arguments is methodological. It is further argued that taking skeptical arguments seriously requires us to adopt a version of 'virtue epistemology', or a theory of knowledge that makes intellectual virtue central in the analysis of knowledge. The above methodology has consequences for moral and religious epistemology; in particular, a theory of moral perception is defended. (shrink)

In "Epistemic Permissiveness", Roger White presents several arguments against Extreme Permissivism, the view that there are possible cases where, given one's total evidence, it would be rational to either believe P, or to believe ~P. In this paper, we carefully reconstruct White's arguments and then argue that they do not succeed.

It is nowadays taken for granted that the core radical sceptical arguments all pivot upon the principle that the epistemic operator in question is 'closed' under known entailments. Accordingly, the standard anti-sceptical project now involves either denying closure or retaining closure by amending how one understands other elements of the sceptical argument. However, there are epistemic principles available to the sceptic which are logically weaker than closure but achieve the same result. Accordingly the contemporary debate fails to engage with the (...) sceptical problem in its strongest form. (shrink)

In the history of philosophical thought, few themes loom as large as skepticism. Skepticism has been the most visible and important part of debates about knowledge. Skepticism at its most basic questions our cognitive achievements, challenges our ability to obtain reliable knowledge; casting doubt on our attempts to seek and understand the truth about everything from ethics, to other minds, religious belief, and even the underlying structure of matter and reality. Since Descartes, the defense of knowledge against skepticism has been (...) one of the primary tasks not just of epistemology but philosophy itself. The Oxford Handbook of Skepticism features twenty-six newly commissioned chapters by top figures in the field. Part One contains articles explaining important kinds of skeptical reasoning. Part Two focuses on responses to skeptical arguments. Part Three concentrates on important contemporary issues revolving around skepticism. As the first volume of its kind, the articles make significant contributions to the debate on skepticism. (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.

My aim in this paper is to develop and defend a novel answer to a question that has recently generated a considerable amount of controversy. The question concerns the normative significance of peer disagreement. Suppose that you and I have been exposed to the same evidence and arguments that bear on some proposition: there is no relevant consideration which is available to you but not to me, or vice versa. For the sake of concreteness, we might picture.

The sceptic about the external world presents us with a paradox: an apparently acceptable argument for an apparently unacceptable conclusion—that we do not know anything about the external world. Some paradoxes, for instance the liar and the sorites, are very hard. The defense of a purported solution to either of these two inevitably deploys the latest in high-tech philosophical weaponry. On the other hand, some paradoxes are not at all hard, and may be resolved without much fuss. They do not (...) contain profound lessons about the human condition. Where should we place the sceptical paradoxes? (shrink)

A rational person doesn’t believe just anything. There are limits on what it is rational to believe. How wide are these limits? That’s the main question that interests me here. But a secondary question immediately arises: What factors impose these limits? A first stab is to say that one’s evidence determines what it is epistemically permissible for one to believe. Many will claim that there are further, non-evidentiary factors relevant to the epistemic rationality of belief. I will be ignoring the (...) details of alternative answers in order to focus on the question of what kind of rational constraints one’s evidence puts on belief. Our main question concerns how far epistemic permission and obligation can come apart.1 Suppose I am epistemically permitted to believe P, i.e., it would not be irrational for me to believe it. Am I thereby obliged to believe P, or are other options rationally available to me?2 Might I be equally rational in remaining agnostic about P, or even believing not-P? Or could even a slightly stronger or weaker degree of confidence be just as reasonable? (shrink)

The brain-in-a-vat argument for skepticism is best formulated, not using the closure principle, but using the “Preference Principle,” which states that in order to be justified in believing H on the basis of E, one must have grounds for preferring H over each alternative explanation of E. When the argument is formulated this way, Dretske’s and Klein’s responses to it fail. However, the strengthened argument can be refuted using a direct realist account of perception. For the direct realist, refuting the (...) SIV scenario is not a precondition on knowledge of the external world, and only the direct realist can give a non-circular account of how we know we’re not brains in vats. (shrink)

In this paper I will address a few of the many questions that fall under the general heading of “the ethics of belief.” In section I I will discuss the adequacy of what has come to be known as the “deontological conception of epistemic justification” in the light of our apparent lack of voluntary control over what we believe. In section II I’ll defend an evidentialist view about what we ought to believe. And in section III I will briefly discuss (...) apparent conflicts between epistemic considerations and moral or other considerations. (shrink)

Much has been written about epistemological skepticism in the last ten or so years, but there remain some unanswered questions concerning the structure of what has become the canonical Cartesian skeptical argument. In this paper, I would like to take a closer look at this structure in order to determine just which epistemic principles are required by the argument.

This paper compares two kinds of epistemic principles---an underdetermination principle and a deductive closure principle. It argues that each principle provides the basis for an independently motivated skeptical argument. It examines the logical relations between the premises of the two kinds of skeptical argument and concludes that the deductive closure argument cannot be refuted without refuting the underdetermination argument. The underdetermination argument, however, can be refuted without refuting the deductive closure argument. In this respect, the deductive closure argument is the (...) stronger of the two. (shrink)