Anthony Brueckner: ~K~SK

In a standard version of a closure-based skeptical argument, there is a premise to the effect that I do not know that a skeptical scenario (such as that I am a brain in a vat) does not obtain—~ K~SK. In this paper, I survey a number of ways of attacking the premise (including that of the epistemological disjunctivist) as well as a number of ways of defending the premise (including that of the proponent of underdetermination considerations).

Aidan McGlynn: On Epistemic Alchemy: Entitlement, Justification, and Closure

Crispin Wright has proposed that one has entitlements to accept various propositions that play a foundational role within one’s body of belief. Such an entitlement is a kind of warrant that does not require the possessor to have acquired evidence speaking in favor of the proposition in question. The proposal allows Wright to concede much of the force of the most powerful arguments for scepticism, while avoiding the truly sceptical conclusion that one is not in a position to rationally claim warrant for most of one’s beliefs. Here I will argue that Wright has underestimated a problem for his proposal, which I’ll call the alchemy problem. ‘Epistemic alchemy’ is Martin Davies term for the conversion of entitlement to accept a proposition into justification to believe it, and the problem for Wright is that his picture seems to allow alchemical conversion to take place. Wright considers a version of this problem, but the version he confronts invokes a closure principle for justification, and his response is to deny that principle. I offer two arguments designed to question the adequacy of this response. Lastly, I explore the idea that epistemic alchemy is not objectionable after all. I argue that the proponent of Wright’s picture who wants to pursue this option faces the difficult task of showing how the alchemy problem differs from Stewart Cohen’s superficially similar ‘problem of easy knowledge’.

Ernest Sosa: Descartes, Scepticism, and Virtue Epistemology

It is a main thesis of this talk that Descartes is a virtue epistemologist. Arguing for this will require us to attain an overview of main elements of Cartesian epistemology, and main elements of contemporary virtue epistemology.  That will put us in a position to appreciate how well the two fit together. As a result, Descartes's distinctive form of skeptical problematic will emerge, as will his distinctive solution; and similarly for the contemporary approach.

Jonathan Vogel: Explanation and the External World

Suppose that our ordinary beliefs about the world provide better explanations of facts about our experience than skeptical hypotheses do. Inference to the best explanation (IBE) would then license our rejection of the sceptical hypotheses in favour of our ordinary beliefs. Critics of this approach object that we have no reason to believe that better explanations are, as such, more likely to be true than worse explanations. I begin by clarifying what the problem facing IBE is supposed to be, and argue that the difficulty is less substantial than many assume. I then take on the objection to IBE directly. I argue that experience confirms our ordinary beliefs more strongly than various skeptical hypotheses of massive sensory deception, and that those beliefs are, therefore, more likely to be true than their skeptical competitors.

Brian Weatherson: Probabilistic Arguments for Scepticism

This paper concerns the following principle connecting rational credence and knowledge acquisition: If E lowers the rational credence in H, then E cannot be the basis for learning (i.e. coming to know) H. The paper starts by arguing that this premise supports a powerful modern version of Hume's argument for inductive scepticism. I then defend the principle against a notable class of putative counterexamples. The defence turns on my version of interest-relative invariantism, which I briefly sketch and defend.

Roger White: Defeasibility and Scepticism

It is tempting to suppose that a phenomenal duplicate of me—my Brain-in-a-Vat-Twin— shares all my perceptual evidence. After all, everything appears the same to him as it does to me. John McDowell, Tim Williamson, and others view this “Cartesian” conception of evidence as a fundamental mistake and the root of external world skepticism. I will raise some problems for their opposing views and suggest that in any event, rejection of the Cartesian conception does little by itself to diffuse the skeptical worry. Part of this will turn on the question of the conditions in which perceptual justification can be defeated. The other part has to do with the rationality of taking certain attitudes concerning one’s own rationality.