This Introduction to the special issue on “Skepticism and Justification” provides a background to the nine articles collected here and a detailed summary of each, which highlights their interconnections and relevance to the debate at the heart of the issue.

The paper reviews the grounds for relativist interpretations of Wittgenstein's later thought, especially in On Certainty . It distinguishes between factual and virtual forms of epistemic relativism and argues that, on closer inspection, Wittgenstein's notes don't support any form of relativism – let it be factual or virtual. In passing, it considers also so-called "naturalist" readings of On Certainty , which may lend support to a relativist interpretation of Wittgenstein's ideas, finds them wanting, and recommends to interpret his positive proposal (...) in On Certainty as a form of "internal rationalism.". (shrink)

Some philosophers, like Mark Richard and Paul Boghossian, have argued against relativism that it cannot account for the possibility of faultless disagreement. However, I will contend that the objections they moved against relativism do not target its ability to account for the possibility of faultless disagreement per se. Ra- ther, they should be taken to challenge its capacity to account for another element of our folk conception of disagreement in certain areas of discourse—what Cris- pin Wright has dubbed parity. What (...) parity demands is to account for the possibil- ity of coherently appreciating, within a committed perspective, that our oppo- nent’s contrary judgement is somehow on a par with our own judgement. Under- stood in this way, Boghossian’s and Richard’s objections put indeed considerable pressure on relativism—or so I will argue. I will consider John MacFarlane’s at- tempt to resist their objections and I will show that, once their arguments are properly understood as targeting parity, the attempt is not successful. In the last section of the paper I will offer a diagnosis of what is at the heart of the relativist inability to account for parity—namely its assumption of a monistic conception of the normativity of truth. (shrink)

This study provides a critical appraisal of Duncan Pritchard’s argument to the effect that ability to preserve certain eminently plausible transmission and/or closure principles for knowledge serves as a powerful adequacy test on alternative accounts of so-called Wittgensteinian certainties or hinge commitments. I argue that Pritchard fails to establish this claim—the transmission test does not favour his favourite conception over alternative conceptions premised on the idea that hinge commitments are not supportable via evidential-cognitive routes.

Several authors have argued that, assuming we have apriori knowledge of our own thought-contents, semantic externalism implies that we can know apriori contingent facts about the empirical world. After presenting the argument, I shall respond by resisting the premise that an externalist can know apriori: If s/he has the concept water, then water exists. In particular, Boghossian's Dry Earth example suggests that such thought-experiments do not provide such apriori knowledge. Boghossian himself rejects the Dry Earth experiment, however, since it would (...) imply that externalism is true of empty concepts as well as non-empty concepts. Yet in this paper I respond by defending empty-concept externalism, from criticisms suggested by Boghossian and Brown, and recently developed further by Besson. My contention is that an externalist can give a non-ad hoc descriptivist account of empty concepts. Accordingly, apriori self-knowledge does not enable an externalist to know contingent features of the external world. (shrink)

In the recent literature on Moore's Proof of an external world, it has emerged that different diagnoses of the argument's failure are prima facie defensible. As a result, there is a sense that the appropriateness of the different verdicts on it may depend on variation in the kinds of context in which the argument is taken to be a move, with different characteristic aims. In this spirit, Martin Davies has recently explored the use of the argument within two different epistemic (...) projects called respectively ‘deciding what to believe’ and ‘settling the question’. Depending on which project is in hand, according to Davies, the diagnoses of its failure—if indeed it fails—will differ. I believe that, by introducing the idea that the effectiveness of a valid argument may be epistemic project-relative, Davies has pointed the way to an important reorientation of the debates about Moore's Proof. But I wish to take issue with much of the detail of his proposals. I argue that Davies's characterization of his two projects is misleading (§1), and his account of their distinction defective (§2). I then canvass some suggestions about how it may be improved upon and about how further relevant kinds of epistemic projects in which Moore's argument may be taken to be a move can be characterized, bringing out how each of these projects impinges differently on the issue of the Proof's failure and of its diagnosis (§§3 and 4). In conclusion (§5) I offer an overview of the resulting terrain. (shrink)

Fred Dretske notoriously claimed that knowledge closure sometimes fails. Crispin Wright agrees that warrant does not transmit in the relevant cases, but only because the agent must already be warranted in believing the conclusion in order to acquire her warrant for the premise. So the agent ends up being warranted in believing, and so knowing, the conclusion in those cases too: closure is preserved. Wright's argument requires that the conclusion's having to be warranted beforehand explains transmission failure. I argue that (...) it doesn't, and that the correct explanation does not imply that the agent will end up warranted in believing the conclusion when transmission fails. Those who agree that transmission does fail in those cases, therefore, might as well follow Dretske in denying knowledge closure too. (shrink)