cannot understand the language.”[1] This is not intended to cover (easily imaginable) cases of recording one's experiences in a personal code, for such a code, however obscure in fact, could in principle be deciphered. What Wittgenstein had in mind is a language conceived as necessarily comprehensible only to its single originator because the things which define its vocabulary are necessarily inaccessible to others.

Our folk epistemology says that if someone knows that P and tells you that P, then, given the absence of defeaters, if you believe what they tell you, you will come to know that P as well. A speaker's knowledge that P is then, for the most part, enough for a hearer to come to know that P. But there are counterexamples to this principle: testimonial knowledge does not always transfer from the speaker to the hearer. Why should that be (...) so? Because testimonial knowledge arises through the flow of information--from conclusive grounds--from the speaker through the speaker's assertion to the hearer's state of comprehension as of the speaker's assertion. A speaker's belief can be based on conclusive grounds, but the speaker's assertion may fail to provide conclusive grounds to the hearer. Then the hearer won't acquire knowledge, even from a knowledgeable speaker. Knowledge from testimony then works more like knowledge through perception. But wait, you say, that can't be so because testimony involves free will but perception does not. The essay ends with a broadly Hume inspired reply to this objection. (shrink)

Some philosophers understand epistemological skepticism as merely presenting a paradox to be solved, a paradox given rise to by some apparently forceful arguments. I argue that such a view needs to be justified, and that the best way to do so is to show that we cannot help seeing skepticism as obviously false. The obviousness (to us) of the falsity of skepticism is, I suggest, explained by the fact that we cannot live without knowledge-beliefs (a knowledge-belief about the world is (...) a belief that a person or a group of people know that p, where p is an empirical proposition about the world). I then go on to argue for the indispensability of knowledge-beliefs. The first line of argument appeals to the practical aspects of our employment of the concept of knowledge, and the second line of argument draws on some Davidsonian ideas concerning understanding and massive agreement. (shrink)

This book takes purism about knowledge as the default position and defends it from the challenges of pragmatic encroachment. The book is divided into two parts, a negative and a positive one. The negative part critically examines existing purist strategies in response to pragmatic encroachment. The positive part provides a new theory of how practical factors can systematically influence our confidence and explores some implications of such influence.

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)

En la obra que ahora presentamos al público hispanoparlante, reunimos diez trabajos previamente publicados en lengua italiana que abordan importantes cuestiones que ocupan en este momento a los estudiosos de la filosofía helenística y romana. Sus autores son diez de los más importantes especialistas italianos actuales en el estudio de este periodo histórico.

If it works, I can use Putnam’s vat argument to show that I have not always been a brain-in-a-vat. It is widely thought that the vat argument is of no use against closure scepticism – that is, scepticism motivated by arguments that appeal to a closure principle. This is because, even if I can use the vat argument to show that I have not always been a BIV, I cannot use it to show that I was not recently envatted, and (...) it is thought that the claim that I am not justified in thinking that I was not recently envatted is all that the closure sceptic requires. In this paper I first argue that scenarios in which I have been recently envatted are inadequate for the sceptic’s purposes, and so the standard argument that the vat argument is of no use against closure scepticism fails. I then argue that it is not possible to revise the standard argument to meet my objection. I conclude that, if it works, I can use the vat argument as a defence against closure scepticism. (shrink)

The Knowledge Norm of Assertion claims that it is proper to assert that p only if one knows that p. Though supported by a wide range of evidence, it appears to generate incorrect verdicts when applied to utterances of “I don't know.” Instead of being an objection to KNA, I argue that this linguistic data shows that “I don't know” does not standardly function as a literal assertion about one's epistemic status; rather, it is an indirect speech act that has (...) the primary illocutionary force of opting out of the speaker's conversational responsibilities. This explanation both reveals that the opt-out is an under-appreciated type of illocutionary act with a wide range of applications, and shows that the initial data in fact supports KNA over its rivals. (shrink)

This paper discusses a common contemporary characterization of skepticism and skeptical arguments-that their real importance is instrumental, that they “drive progress in philosophy.“ I explore two possible contrasts to the idea that skepticism's significance is thus wholly methodological. First, I recall for the reader a range of views that can be understood as `truth in skepticism' views. These concessive views are those most clearly at odds with the idea that skepticism is false, but instrumentally valuable. Considering the contributions of such (...) `truth in skepticism' theorists, I argue, shows that the good of furthering philosophical progress is partly achieved by the work of those who would reject the `merely methodological' view of skepticism's import. While this shows such a view of skepticism's import to be partially self-effacing, it is not therefore incoherent. Rather, the characterization is revealed to be wedded to particular diagnoses of skepticism, and not independently innocuous or neutral. Second, I discuss the idea that the `merely methodological' characterization of skepticism's import draws a contrast with philosophical positions or theses that are supposed to have practical teeth. Here, I think the danger of acquiescing too readily to this view is that the normative import of skeptical arguments is obscured. At a time when discussions of the value of knowledge are in ascendency, this in particular seems a loss-a route from consideration of skeptical arguments to broader normative questions worth keeping open is rather more obscured than opened up. Any radically revisionary outcome of an encounter with skepticism is less likely, led by such an understanding, just when there is opportunity instead to connect up with broad questions of epistemic value. For these reasons I argue the characterization is not one to too readily, unthinkingly, endorse. (shrink)

In this paper, I consider how a general epistemic norm of action that I have proposed in earlier work should be specified in order to govern certain types of acts: assertive speech acts. More specifically, I argue that the epistemic norm of assertion is structurally similar to the epistemic norm of action. First, I argue that the notion of warrant operative in the epistemic norm of a central type of assertion is an internalist one that I call ‘discursive justification.’ This (...) type of warrant is internalist insofar as it requires that the agent is capable of articulating reasons for her belief. The idea, roughly, is that when one asserts that p, one is supposed to be in a position to give reasons for believing that p. Bonjour’s reliable clairvoyant Norman, for example, is not in an epistemic position to make assertions regarding the president’s whereabouts—even if Norman knows the president’s whereabouts. In conclusion, I briefly consider whether a type of skeptical argument—often labeled Agrippa’s Trilemma—is motivated, at least in part, by the fact that responses to it violate the relevant epistemic norm of assertion. (shrink)

This paper applies speech-act theory to craft a new response to Pyrrhonian skepticism and diagnose its appeal. Carefully distinguishing between different levels of language-use and noting their interrelations can help us identify a subtle mistake in a key Pyrrhonian argument.

Scholarship on ancient skepticism has undergone a remarkable renaissance in the last three decades. Specialists in ancient philosophy have explored the complex history of the Greco‐Roman skeptical traditions and discussed difficult philological and exegetical issues. But they have also assessed the philosophical significance of the various ancient skeptical outlooks. In this first paper, I provide a general presentation of this area of study, while in the two subsequent articles I will focus on some of the topics that have been the (...) object of much attention in the recent literature on ancient skepticism. (shrink)

Pyrrhonism was one of the two main ancient skeptical traditions. In this second paper of the three‐part series devoted to ancient skepticism, I present and discuss some of the issues on Pyrrhonian skepticism which have been the focus of much attention in the recent literature. The topics to be addressed concern the outlooks of Pyrrho, Aenesidemus, and Sextus Empiricus.

In this paper, we examine Sextus Empiricus' treatise Against the geometers . We first set this treatise in the overall context of the sceptic's polemics against the liberal arts. After a discussion of Sextus' attitude to the quadrivium , we discuss the structure, the sources and the target of the Against the geometers . It appears that Euclid is not Sextus' source, and neither he, nor the professional geometers, seem to be Sextus' main targets. Of course, Sextus never really makes (...) clear his precise target, but his attacks are rather directed against geometry as a means of modelling the physical world, thus ruining the support geometry was intended to bring to the physical part of dogmatic philosophy. (shrink)

Many philosophers now argue that the doubts of the philosophical sceptic are unnatural ones, in that they are not forced on us by considerations that any reasonable person would have to accept as compelling but only arise if one has already accepted certain controversial theoretical commitments. In this article I defend the naturalness of philosophical scepticism against such criticisms. After defining "global ontological scepticism," I examine the work of a number of anti-sceptical philosophers—Michael Huemer, Michael Williams, and John McDowell. Although (...) McDowell does move the debate to a deeper level by interpreting scepticism as a challenge to the very possibility of the mind's apprehending reality by being in a rational rather than a merely causal relation to it, none of them succeeds in showing that global ontological scepticism is, in the relevant sense, unnatural. This is not to say that the sceptic is correct; simply that it has not been shown that we can reasonably dismiss the sceptical questions and thereby evade the need to engage seriously with the sceptical arguments. (shrink)

A skeptic claims that I do not have knowledge of the external world. It has been thought that the skeptic reaches this conclusion because she employs unusually stringent standards for knowledge. But the skeptic does not employ unusually high standards for knowledge. Rather, she employs unusually restrictive standards of evidence. Thus, her claim that we lack knowledge of the external world is supported by considerations that would equally support the claim that we lack evidence for our beliefs about the external (...) world. These considerations do not threaten the truth of our ordinary attributions of evidence, however, for such attributions are context-sensitive in their semantics. It is argued that this solution to the problem of the external world enjoys all of the benefits, and suffers none of the problems, of other solutions to the problem of the external world. (shrink)

The aim of this paper is to vindicate the Cartesian quest for certainty by arguing that to aim at certainty is a constitutive feature of cognition. My argument hinges on three observations concerning the nature of doubt and judgment: first, it is always possible to have a doubt as to whether p in so far as one takes the truth of p to be uncertain; second, in so far as one takes the truth of p to be certain, one is (...) no longer able to genuinely wonder whether p is true; third, to ask the question whether p is to desire to receive a true answer. On this ground I clarify in what sense certainty is the aim of cognition. I then argue that in judging that p we commit ourselves to p’s being certain and that certainty is the constitutive norm of judgment. The paper as a whole provides a picture of the interplay between doubt and judgment that aims at vindicating the traditional insight that our ability to doubt testifies our aspiration to know with absolute certainty. (shrink)

The scientific community, we hold, often provides society with knowledge—that the HIV virus causes AIDS, that anthropogenic climate change is underway, that the MMR vaccine is safe. Some deny that we have this knowledge, however, and work to undermine it in others. It has been common to refer to such agents as “denialists”. At first glance, then, denialism appears to be a form of skepticism. But while we know that various denialist strategies for suppressing belief are generally effective, little is (...) known about which strategies are most effective. We see this as an important first step toward their remediation. This paper leverages the approximate comparison to various forms of philosophical skepticism to design an experimental test of the efficacy of four broad strategies of denial at suppressing belief in specific scientific claims. Our results suggest that assertive strategies are more effective at suppressing belief than questioning strategies. (shrink)

I first argue that the skeptic needs an internalist conception of justification for her argument for skepticism. I then argue that the skeptic also needs to show that we do not have perceptual access to the world if her skepticism is to be a real threat to human knowledge of the world. This, I conclude, puts the skeptic in a dilemma, for internalist conceptions of justification presuppose that we have perceptual access to the world.

According to David Lewis, the predicate ‘knows’ is context-sensitive in the sense that its truth conditions vary across conversational contexts, which stretch or compress the domain of error possibilities to be eliminated by the subject’s evidence. Our concern in this paper is to thematize, assess, and overcome within a neo-Lewisian contextualist project two important mismatches between our use of ‘know’ in ordinary life and the use of ‘know’ by ‘Lewisian’ ordinary speakers. The first mismatch is that Lewisian contextualism still overgenerates (...) the error possibilities which cannot be ignored in a given context, since it is oblivious to the distinction between ‘invented’ and ‘discovered’ possibilities. The second mismatch is a full-scale one: an adequate account of knowledge attribution is not exhausted by the subject’s negative capacity of pruning branches off the tree of counterpossibilities. We therefore introduce a new vector of value, which explains how ‘know’ comes in degrees: the satisfaction of ‘know better’ is made to depend on the capacity of imagining possibilities connected in a relevant way with the subject’s beliefs. (shrink)

Infallibilism is the claim that knowledge requires that one satisfies some infallibility condition. I spell out three distinct such conditions: epistemic, evidential and modal infallibility. Epistemic infallibility turns out to be simply a consequence of epistemic closure, and is not infallibilist in any relevant sense. Evidential infallibilism i s unwarranted but it is not an satisfactory characterization of the infallibilist intuition. Modal infallibility, by contrast, captures the core infallibilist intuition, and I argue that it is required to solve the Gettier (...) problem and account for lottery cases. Finally, I discuss whether modal infallibilism has sceptical consequences and argue that it is an open question whose answer depends on one’s account of alethic possibility. (shrink)

In this paper I discuss the relation between various properties that have been regarded as important for determining whether or not a belief constitutes a piece of knowledge: its stability, strength and sensitivity to truth, as well as the strength of the epistemic position in which the subject is with respect to this belief. Attempts to explicate the relevant concepts more formally with the help of systems of spheres of possible worlds (à la Lewis and Grove) must take care to (...) keep apart the very different roles that systems of spheres can play. Nozicks sensitivity account turns out to be closer to the stability analysis of knowledge (versions of which I identify in Plato, Descartes, Klein and Lehrer) than one might have suspected. (shrink)

The Mode of Relativity in Agrippa’s Five Modes does not fit with the other four modes, and disrupts an otherwise elegant system. We argue that it is not the familiar argument from epistemic relativism, but a formal condition on the structure of justifications: the principle that epistemic grounding relations cannot be reflexive. This understanding of Agrippan Relativity leads to a better understanding of the Modes of Hypothesis and Reciprocity, a clearer outline of the structure of Agrippa’s system as a whole, (...) and a new insight into the Two Modes that follow the Five. (shrink)

Recent literature on skepticism has raised a nearly univocal voice in condemning skeptical argumentation on the grounds that such argumentation necessarily involves our adopting some nonordinary or unnatural perspective. Were this really so, then skeptical conclusions would not speak to us in the way in which skeptics think they do: We would be "insulated" from any such conclusions. I argue that skeptical argumentation need not rely on any nonordinary or unnatural standards. Rather, the skeptic's procedure is to offer a critique (...) from within. Having given my argument for this claim (which I call the 'continuity argument'), I consider and respond to two important objections. I conclude that the skeptic has a powerful meta-argument to be deployed in defending the legitimacy of his skeptical conclusions against the slings and arrows of (those I call) the half-true theorists. (shrink)

In this article I examine M. Williams’ antisceptical strategy of considering skepticism as an unnatural position philosophically charged, which for him implies that skepticism has nothing to do with our epistemic practices. I admit that this strategy is really promising, especially when applied to Cartesian scepticism. However, when it faces an older ancestor of Cartesian scepticism, Pyrrhonian scepticism, this situation changes. I concentrate on Fogelin’s neopyrrhonist proposal and how Williams’ strategy would face it. I will defend that Pyrrhonian scepticism is (...) a completely natural kind of scepticism according to our epistemic practices. I will also maintain that this kind of skepticism is the unavoidable result of reflecting about those epistemic practices. (shrink)

In this paper I assess the two central ingredients of Laurence BonJour’s position on empirical knowledge that have survived the transition from his earlier coherentist views to his current endorsement of the doctrine of the given: his construal of the problem of the epistemic regress and his rejection of an internalist solution to the problem. The bulk of the paper is devoted to a critical assessment of BonJour’s arguments against externalism. I argue that they fail to put real pressure on (...) externalism, as they rely on a highly questionable conception of epistemic rationality and responsibility. Then, more briefly, I take issue with BonJour’s endorsement of the irrelevance thesis—the claim that even if externalism were true it would not offer a satisfactory solution to the epistemic regress problem. I contend that he is not entitled to subscribe this thesis unless he is prepared to abandon his construal of the problem. (shrink)

Disjunctivism is the view that perceptual experience is either constituted by fact in the world or mere appearance. This view is said to be able to guarantee our cognitive contact with the world, and thus remove a crucial “prop” upon which skepticism depends. This paper has two aims. First, it aims to show that disjunctivism is a solution to Cartesian skepticism. Cartesian skepticism is an epistemological thesis, not an ontological one. Therefore, if there is an external world, we may well (...) undergo a veridical experience, and thus we can take advantage of disjunctivism to adopt an anti-evidential-skepticism strategy to counter Cartesian skepticism. Second, this paper argues that disjunctivism fails to solve Pyrrhonian skepticism. To counter Pyrrhonian skepticism, one has to give reasons both for his belief and for his believing. But disjunctivism can only account the former, that is, the reason for the content of perceptual belief. Given that one’s experience in good case and bad case is subjectively indistinguishable, one cannot just use his experience to justify his believing. This shows that disjunctivism cannot meet the requirement to provide an adequate account for reflective knowledge. (shrink)

I argue in this paper that, like the Pyrrhonism of Sextus Empiricus, Wittgenstein’s response to negative–dogmatic skepticism in On Certainty turns on the attempt to free us from the demands of traditional philosophy and is therefore not a philosophical position, strictly speaking. Rather, it is a therapeutic metaphilosophy designed to bring into view (i.e., to illumine) the relationship between our everyday epistemic practices and those of philosophy such that we simultaneously come to recognize (a) what I call the pragmatic–transcendental self–standingness (...) of the everyday and (b) its philosophical–rational groundlessness. The Pyrrhonian illumination of the everyday is therapeutic in that it aims to purify our metadoxastic attitudes of dogmatism. (shrink)

Through a new interpretation of Wittgenstein's rule-following discussions, this article defends a negotiating model of normativity according to which normative authority is always subject to contestation. To refute both individualism and collectivism, I supplement Wittgenstein's Private Language Argument with a Social Language Argument, showing that normativity cannot be monopolized either individually or socially (i.e. it cannot be privatized or collectivized). The negotiating view of normativity here developed lays the foundations of a politics of radical contestation which converges with Chantal Mouffe's (...) framework of 'radical democracy', while departing from her agonism in preserving the structuring and constraining role that tacit agreement in action plays in rule-following practices. My account of the 'burdens of eccentricity' elucidates how the normative force of dissidence can be properly recognized and used effectively for social transformations. I argue that there is a 'presumption of normalcy' in favour of the established consensus of action, but that this presumption is defeasible: in normative disagreements, a violation of expected normalcy shifts the burden onto the shoulders of rebellious agents who must show that their dissenting behaviour can be a legitimate extension, revision, or transformation of the practice in question. (shrink)

Prominent instances of anti-luck epistemology, in particular sensitivity and safety accounts of knowledge, introduce a modal condition on the pertinent belief in terms of closeness or similarity of possible worlds. Very roughly speaking, a belief must continue to be true in close possibilities in order to qualify as knowledge. Such closeness-accounts derive much support from their (alleged) ability to eliminate standard instances of epistemic luck as they appear in prominent Gettier-type examples. The article argues that there are new Gettier-type examples (...) which are grounded in “distant” epistemic luck. It is demonstrated that sensitivity and safety theories cannot handle such examples. (shrink)

Although the fallible/infallible distinction in the theory of knowledge has traditionally been upheld by most epistemologists, almost all contemporary theories of knowledge claim to be fallibilist. Fallibilists have, however, been forced to accommodate knowledge of necessary truths. This has proved to be a daunting task, not least because there is as yet no consensus on how the fallible/infallible divide is to be understood. In this article, after examining and rejecting a number of representative accounts of the notion of fallible knowledge, (...) I argue that the main problems with these accounts actually stem from the very coherence of that notion. I then claim that the distinction is best understood in terms of the externalist/internalist conceptions of knowledge. Finally, I seek to garner some independent support for the proposal by highlighting some of its consequences, including its surprising bearing on certain recent and seemingly distant controversies involving issues in epistemology and philosophy of mind. (shrink)

Stephen Schiffer has argued that contextualist solutions to skepticism rest on an implausible "error theory" concerning our own semantic intentions. Similar arguments have recently been offered also by Thomas Hofweber and Patrick Rysiew. I attempt to show how contextualists can rebut these arguments. The kind of self-knowledge that contextualists are committed to denying us is not a kind of self-knowledge that we need, nor is it a kind of self-knowledge that we can plausibly be thought to possess.

This paper aims to reconstruct the overarching logical structure of Michael Williams's response to philosophical skepticism. One goal is to forestall overhasty dismissals of his position based on failures to understand the logical relations among his various anti‐skeptical claims and arguments. In many places, Williams suggests that the strategy he calls “theoretical diagnosis” is sufficient to defuse the skeptical challenge and that, accordingly, his anti‐skeptical strategy consists solely in developing theoretical diagnoses. According to the account developed here, this claim is (...) misleading—in need of significant qualification, if not outright false. Even so, the paper concludes that, in its essentials, Williams's response is structurally sound, given his understanding of the problem posed by skepticism. The paper ends with a brief assessment of the merits of that response. (shrink)

In his 2014 article “Motivations for Relativism as a Solution to Disagreements”, Steven Hales argues that relativism is a plausible disagreement resolution strategy for epistemically irresolvable disagreements. I argue that his relativistic strategy is not adequate for disagreements of this kind, because it demands an impossible doxastic state for disputants to resolve the disagreement. Contrarily, Fogelin’s :1–8, 1985) theory of deep disagreement does not run into the same problems. Deep disagreements, according to Fogelin, cannot be resolved through argumentation because the (...) conditions for argumentation are lacking in such contexts. I advance the view that deep disagreements arise due to differences in disputants’ mutually supporting interrelated beliefs. This view avoids the hurdles caused by the tiered structure of support found at the heart of Hales’s view on disagreement: the assumption that belief and perspective can be separated, and that disagreement is located. (shrink)

This paper argues that for someone to know proposition p inferentially it is not enough that his belief in p and his justification for believing p covary with the truth of p through a sphere of possibilities. A further condition on inferential knowledge is that p's truth-maker is identical with, or causally related to, the state of affairs the justification is grounded in. This position is dubbed ‘identificationism.’.

In his ‘Outlines of Pyrrhonism’ Sextus Empiricus compares the Pyrrhonean arguments with a purge, which forces the subject to give up both the philosophical beliefs and the Pyrrhonean arguments. It is shown that this strategy leads to serious troubles: Insofar the Pyrrhonean arguments are at least partly philosophical in nature, they lead to a contradiction in the subject’s beliefs about his own beliefs. But this does not help the Pyrrhonist to reach his goal: On the one hand, facing a contradiction, (...) some, but not all beliefs of a given discourse should be given up. On the other hand, the contradiction is not avoidable: In this respect, the metaphor of a “purge” is misleading: The presupposed timely dimension has no counterpart in logical reasoning. (shrink)