After providing some historical and systematic background, I introduce the structure of a very natural and influential sceptical underdetermination argument. The argument assumes that it is metaphysically possible for a deceived subject to have the same evidence that a non-deceived subject has, and tries to draw consequences about justification from that assumption of metaphysical possibility. I first variously object to the transition from the assumption to its supposed consequences. In the central part of the paper, I then critically consider some (...) influential ways of bridging the gap between the assumption and its supposed consequences, which generally consist in strengthening the assumption from one of metaphysical possibility into one of either counterfactual implication or entailment. The discussion indicates that epistemic facts are much more independent from metaphysically modal facts than the sceptical underdetermination argument requires. (shrink)

The aim of this paper is to analyse and develop how scepticism becomes an intelligible question starting from requirements that epistemologists themselves aim to endorse. We argue for and defend the idea that the root of scepticism is the underdetermination principle by articulating its specificitya respectable epistemic principle and by defending it against objections in current literature. This engagement offers a novel understanding of underdetermination-based scepticism. While most anti-sceptical approaches challenge scepticism by understanding it as postulating uneliminated scenarios of mass (...) deception, or as endorsing unnatural epistemic requirements, we argue here that both contentions are mistaken. Underdetermination-based scepticism targets our beliefs by issuing a genuine question about the rational support they enjoy. If we cannot establish that the sources of our beliefs provide them the required epistemic merit and authority, they lack non-arbitrary grounds. This has a sizable impact on what constitutes a satisfactory anti-sceptical strategy. Strategies that merely focus on the scenario-based aspect of scepticism, or on the truth-functional evaluation of our beliefs, are shown to miss the mark of the sceptical threat. The proposed analysis ultimately provides a shift in perspective concerning the character and reach of philosophical doubt. (shrink)

Epistemologists understand radical skepticism as arising from two principles: Closure and Underdetermination. Both possess intuitive prima facie support for their endorsement. Understanding how they engender skepticism is crucial for any reasonable anti-skeptical attempt. The contemporary discussion has focused on elucidating the relationship between them to ascertain whether they establish distinct skeptical questions and which of the two constitutes the ultimately fundamental threat. Major contributions to this debate are due to Brueckner, Cohen, and Pritchard. This contribution aims at defending Brueckner’s contention (...) that underdetermination expresses the fundamental skeptical threat and that the closure-based argument can ultimately be reduced to it, at least concerning skeptical contexts. This will be achieved by undermining Cohen’s objections to Brueckner on both counts. Cohen’s argument endorses a picture of evidential underdetermination, which, while apt for non-skeptical contexts, cannot be applied to radical skepticism. A comparison with a case of scientific underdetermination is developed to argue for this idea. Our argument is then applied to the principle equivalence issue and to objections against it. It is then shown how this analysis possesses a distinctive effect on our understanding of the skeptical threat and the assessment of successful anti-skeptical strategies. (shrink)

Epistemological disjunctivism, as defended by, for example, McDowell, Neta and Pritchard, is the view that epistemic justification can be – and in paradigmatic cases of perceptual knowledge actually is – both factive and reflectively accessible. One major problem for this view is the access problem: apparently, epistemological disjunctivism entails that ordinary external world propositions can be known by reflection alone. According to epistemological disjunctivism, seeing that the sun is shining is reflectively accessible and seeing that the sun is shining entails (...) that it is. Assuming closure of reflective knowledge under known entailment it is also reflectively knowable that the sun is shining. Drawing on joint work with Neta, Pritchard replies that disjunctivism is not committed to this absurdity, but only to the possibility of reflective access to empirical reasons. In this article I offer an interpretation of this reply, but also an objection to it: my interpretation is based on applying the source/content distinction to epistemic reasons. My objection is based on arguing that the access problem is a problem for any version of access internalism. Although Pritchard's reply solves the general access problem, it does not solve the access problem that is generated by the specific commitments of epistemological disjunctivism. Due to the transparency of self-knowledge of propositional perception, epistemological disjunctivism cannot meet a central requirement for applying the source/content distinction. (shrink)

Cartesian skepticism about epistemic justification (‘skepticism’) is the view that many of our beliefs about the external world – e.g., my current belief that I have hands – aren’t justified. I examine the two most influential arguments for skepticism – the Closure Argument and the Underdetermination Argument – from an evidentialist perspective. For both arguments it is clear which premise the anti-skeptic must deny. The Closure Argument, I argue, is the better argument in that its key premise is weaker than (...) the Underdetermination Argument’s key premise. However, it’s also likely that the motivation for accepting both key premises is exactly the same. So there may be a sense in which both arguments provide exactly the same motivation for skepticism. Then I argue that if I I’m right about what the motivation for accepting the arguments’ key premises is, then neither argument succeeds in providing a good reason to accept skepticism. I conclude by explaining why I think epistemologists are right to expend a lot of time and effort on refuting these arguments, even if neither argument provides any motivation for skepticism. (shrink)

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.

Anthony Brueckner has argued that claims about underdetermination of evidence are suppressed in closure-based scepticism (“The Structure of the Skeptical Argument”, Philosophy and Phenomenological Research 54:4, 1994). He also argues that these claims about underdetermination themselves lead to a paradoxical sceptical argument—the underdetermination argument—which is more fundamental than the closure argument. If Brueckner is right, the status quo focus of some predominant anti-sceptical strategies may be misguided. In this paper I focus specifically on the relationship between these two arguments. I (...) provide support for Brueckner’s claim that the underdetermination argument is the more fundamental sceptical argument. I do so by responding to a challenge to this claim put forward by Stewart Cohen (“Two Kinds of Skeptical Argument”, Philosophy and Phenomenological Research 58:1, 1998). Cohen invokes an alternative epistemic principle which he thinks can be used to challenge Brueckner. Cohen’s principle raises interesting questions about the relationship between evidential considerations and explanatory considerations in the context of scepticism about our knowledge of the external world. I explore these questions in my defence of Brueckner. (shrink)

The relation of scepticism to infallibilism and fallibilism is a contested issue. In this paper I argue that Cartesian sceptical arguments, i.e. sceptical arguments resting on sceptical scenarios, are neither tied to infallibilism nor collapse into fallibilism. I interpret the distinction between scepticism and fallibilism as a scope distinction. According to fallibilism, each belief could be false, but according to scepticism all beliefs could be false at the same time. However, to put this distinction to work sceptical scenarios have to (...) be understood as ignorance-possibilities, not as error-possibilities. To show that scepticism is not tied to infallibilism I reject the principle of unrestricted relevance according to which any error- or ignorance-possibility whatsoever is relevant. Instead I argue that the sceptic should distinguish between local and global ignorance-possibilities. Global ignorance-possibilities are relevant even though not all ignorance-possibilities are relevant. The result is a refined version of the Cartesian sceptical argument that avoids two traps other versions do not avoid. (shrink)