I argue that we can achieve certainty about some empirical propositions. When someone is having a migraine and attending to it, she can be certain that she is in pain. I show that examples intended to undermine claims of certainty or to raise doubts about the reliability of introspection do not touch such cases. Traditional foundationalists have held that epistemically certain beliefs can serve as the basis for all one’s other justified beliefs. This is not so, because those beliefs that (...) are certain are spread too thinly to serve as broad justificatory foundations. Certainty has a different role. The best explanation for the existence of epistemically certain empirical beliefs is experientialism, the view that nondoxastic sensory experiences can justify beliefs. Experientialism then offers a framework for showing how the stream of sensory experiences can provide an adequate basis for the justification of our ordinary beliefs about the external world. (shrink)

Nick Bostrom argues that if we accept some plausible assumptions about how the future will unfold, we should believe we are probably not humans. The argument appeals crucially to an indifference principle whose precise content is a little unclear. I set out four possible interpretations of the principle, none of which can be used to support Bostrom’s argument. On the first two interpretations the principle is false, on the third it does not entail the conclusion, and on the fourth it (...) only entails the conclusion given an auxiliary hypothesis that we have no reason to believe. (shrink)

_ Source: _Page Count 29 Underdetermination arguments for skepticism maintain that our common sense view of the external world is no better, evidentially speaking, than some skeptical competitors. An important and well-known response by dogmatists, those who believe our commonsense view is justified, appeals to abduction or inference to the best explanation. The predominant version of this strategy, going back at least to Locke, invokes Occam’s razor: dogmatists claim the common sense view is simpler than any of its skeptical alternatives (...) and so has more to recommend it, evidentially speaking. This dispute has overshadowed another possible view: skeptical dogmatism. Skeptical dogmatists hold that we are justified in believing that the common sense view is probably false. I argue that skeptical dogmatism presents some interesting complications to the dialectic between the dogmatist and the skeptic. On the one hand, even if the dogmatist’s use of Occam’s razor is sufficient to rebut skepticism, in itself it is not sufficient to refute skeptical dogmatism. On the other hand, skeptics themselves, ironically, must, given the assumptions of the paper, appeal to something like Occam’s razor in order to avoid capitulating to skeptical dogmatism. (shrink)

Laurence BonJour, among others, has argued that inference to the best explanation allows us to reject skeptical hypotheses in favor of our common-sense view of the world. BonJour considers several skeptical hypotheses, specifically: our experiences arise by mere chance, uncaused; the simple hypothesis which states merely that our experiences are caused unveridically; and an elaborated hypothesis which explains in detail how our unveridical experiences are brought about. A central issue is whether the coherence of one’s experience makes that experience more (...) likely to be veridical. BonJour’s recent treatment of “analog” and “digital” skeptical hypotheses is also discussed. I argue that, although there are important lessons to be learned from BonJour’s writings, his use of inference to the best explanation against skepticism is unsuccessful.Keywords: BonJour; Explanation; Inference to the best explanation; Skepticism; Confirmation; Probability; Coherence; External world. (shrink)

In this paper we make three points about justification of propositions by coherence “from scratch”, where pieces of evidence that are coherent have no individual credibility. First, we argue that no matter how many pieces of evidence are coherent, and no matter what relation we take coherence to be, coherence does not make independent pieces of evidence with no individual credibility credible. Second, we show that an intuitively plausible informal reasoning for justification by coherence from scratch is deficient since it (...) relies on an understanding of “individual credibility” inappropriate for justification from scratch. Third, we show that coherence, when it is recurrent, can make independent sources of evidence with no individual credibility credible. We describe specifically a case in which the same group of independent witnesses with no individual credibility repeatedly produce reports that are in agreement with each other, and their reports become credible as a result. (shrink)

This article surveys work in epistemology since the mid-1980s. It focuses on contextualism about knowledge attributions, modest forms of foundationalism, and the internalism/externalism debate and its connections to the ethics of belief.

The Sellarsian dilemma is a powerful argument against internalistic foundationalist views that aim to end the regress of reasons in experiential states. Laurence BonJour once defended the soundness of this dilemma as part of a larger argument for epistemic coherentism. BonJour has now renounced his earlier conclusions about the dilemma and has offered an account of internalistic foundationalism aimed, in part, at showing the errors of his former ways. I contend that BonJour’s early concerns about the Sellarsian dilemma are correct, (...) and that his latest position does not adequately handle the dilemma. I focus my attention on BonJour’s claim that a nonconceptual experiential state can provide a subject with a reason to believe some proposition. It is crucial for the viability of internalistic foundationalism to evaluate whether this claim is true. I argue it is false. The requirement that the states that provide justification give reasons to a subject conflicts with the idea that these states are nonconceptual. In the final section I consider David Chalmers’s attempt to defend a view closely similar to BonJour’s. Chalmers’s useful theory of phenomenal concepts provides a helpful framework for identifying a crucial problem with attempts to end the regress of reasons in pure experiential states. (shrink)

In this article I focus on some unduly neglected common-sense considerations supporting the view that one's evidence is the propositions that one knows. I reply to two recent objections to these considerations.

According to the explanationist, we can rely on inference to best explanation to justifiably believe familiar skeptical hypotheses are false. On this view, commonsense beliefs about the existence and character of familiar, medium-sized dry goods provides the best explanation of our evidence and so justifies our belief that we're not brains-in-vats. This explanationist approach seems prima facie plausible until we press the explanationist to tell us what the data is that we're trying to explain by appeal to our beliefs about (...) external objects and how we could have access to it. (shrink)

Responses to skeptical arguments need to be serious: they need to explain not only why some premise of the argument is false, but also why the premise is plausible, despite being false. Moorean responses to skeptical arguments are inadequate because they are not serious: they do not explain the plausibility of false skeptical premises. Skeptical arguments presuppose the truth of the following two claims: the requirements for epistemic justification are internalist, and these internalist requirements are never satisfied. In this paper, (...) I provide a serious response to the skeptic on behalf of the internalist: I explain why the claim that internalist requirements are never satisfied is plausible but false. First, I argue that the claim is plausible, but only insofar as one lacks an account of how perceptual experiences make it rational to hold beliefs about the external world. Second, I provide such an account of experiential rationality, and I argue that in light of this account John McDowell can be understood as persuasively arguing that the claim that internalist requirements are never satisfied is false. (shrink)

The concept of evidence is among the central concerns of epistemology broadly construed. As such, it has long engaged the intellectual energies of both philosophers of science and epistemologists of a more traditional variety. Here I briefly survey some of the more important ideas to have emerged from this tradition of reflection. I then look somewhat more closely at an issue that has recently come to the fore, largely as a result of Williamson's Knowledge and Its Limits: that of whether (...) one's evidence supervenes on one's non-factive mental states. (shrink)

Traditional epistemology has, in the main, presupposed that the primary task is to give a complete account of the concept knowledge and to state under what conditions it is possible to have it. In so doing, most accounts have been hierarchical, and all assume an idealized knower. The assumption of an idealized knower is essential for the traditional goal of generating an unassailable account of knowledge acquisition. Yet we, as individuals, fail to reach the ideal. Perhaps more important, we have (...) epistemic goals not addressed in the traditional approach – among them, the ability to reach understanding in areas we deem important for our lives. Understanding is an epistemic concept. But how we obtain it has not traditionally been a focus. Developing an epistemic account that starts from a set of assumptions that differ from the traditional starting points will allow a different sort of epistemic theory, one on which generating understanding is a central goal and the idealized knower is replaced with an inquirer who is not merely fallible but working from a particular context with particular goals. Insight into how an epistemic account can include the particular concerns of an embedded inquirer can be found by examining the parallels between ethics and epistemology and, in particular, by examining the structure and starting points of virtue accounts. Here I develop several interrelated issues that contrast the goals and evaluative concepts that form the structure of both standard, traditional epistemological and ethical theories and virtue–centered theories. In the end, I sketch a virtue–centered epistemology that accords with who we are and how we gain understanding. (shrink)

Many virtue epistemologists conceive of epistemic competence on the model of skill —such as archery, playing baseball, or chess. In this paper, I argue that this is a mistake: epistemic competences and skills are crucially and relevantly different kinds of capacities. This, I suggest, undermines the popular attempt to understand epistemic normativity as a mere special case of the sort of normativity familiar from skilful action. In fact, as I argue further, epistemic competences resemble virtues rather than skills—a claim that (...) is based on an important, but often overlooked, difference between virtue and skill. The upshot is that virtue epistemology should indeed be based on virtue, not on skill. (shrink)

If Husserl is correct, phenomenological inquiry produces knowledge with an extremely high level of epistemic warrant or justification. However, there are several good reasons to think that we are highly fallible at carrying out phenomenological inquiries. It is extremely difficult to engage in phenomenological investigations, and there are very few substantive phenomenological claims that command a widespread consensus. In what follows, I introduce a distinction between method-fallibility and agent-fallibility, and use it to argue that the fact that we are fallible (...) phenomenologists does not undermine Husserl’s claims concerning the epistemic value of phenomenological inquiry. I will also defend my account against both internalist and externalist objections. (shrink)

If Husserl is correct, phenomenological inquiry produces knowledge with an extremely high level of epistemic warrant or justification. However, there are several good reasons to think that we are highly fallible at carrying out phenomenological inquiries. It is extremely difficult to engage in phenomenological investigations, and there are very few substantive phenomenological claims that command a widespread consensus. In what follows, I introduce a distinction between method-fallibility and agent-fallibility, and use it to argue that the fact that we are fallible (...) phenomenologists does not undermine Husserl’s claims concerning the epistemic value of phenomenological inquiry. I will also defend my account against both internalist and externalist objections. (shrink)

I argue that our justification for beliefs about the external physical world need not be constituted by any justified beliefs about perceptual experiences. In this way our justification for beliefs about the physical world may be nondoxastic and this differentiates my proposal from traditional foundationalist theories such as those defended by Laurence BonJour, Richard Fumerton, and Timothy McGrew. On the other hand, it differs from certain non-traditional foundationalist theories such as that defended by James Pryor according to which perceptual experience (...) is sufficient to justify beliefs about the external world. I propose that justification for propositions describing our perceptual experiences partially constitutes any justification we may possess for beliefs concerning the external world. In this way, our justification for beliefs about the physical world may only be inferential since it is grounded in any justification we have for at least one other proposition. This theory occupies an intermediate position between the two aforementioned foundationalist accounts, which allows it to sidestep problems that confront each of them. (shrink)

The “problem of memory” in epistemology is concerned with whether and how we could have knowledge, or at least justification, for trusting our apparent memories. I defend an inductive solution—more precisely, an abductive solution—to the problem. A natural worry is that any such solution would be circular, for it would have to depend on memory. I argue that belief in the reliability of memory can be justified from the armchair, without relying on memory. The justification is, roughly, that my having (...) the sort of experience that my apparent memory should lead me to expect is best explained by the hypothesis that my memories are reliable. My solution is inspired by Harrod’s (1942) inductive solution. Coburn (1960) argued that Harrod’s solution contains a fatal flaw. I show that my solution is not vulnerable to Coburn’s objection, and respond to a number of other, recent and likely objections. (shrink)

Some philosophers argue that we are justified in rejecting skepticism because it is explanatorily inferior to more commonsense hypotheses about the world. Focusing on the work of Jonathan Vogel, I show that this “abductivist” or “inference to the best explanation” response rests on an impoverished explanatory framework which ignores the explanatory gap between an object's having certain properties and its appearing to have those properties. Once this gap is appreciated, I argue, the abductivist strategy is defeated.

The dream sceptic argues that our ordinary beliefs are not justified because we cannot know that we have not always been dreaming. This is the Always Dreaming Hypothesis (ADH). I develop the traditional coherence objection to dream scepticism and argue that the coherence objection can be reformulated in a way that makes it both plausible and defensible. Considerations about the incoherence of dreams can be given probabilistic expression in a way that shows ADH to be highly improbable. Given the evidence (...) of coherence, ADH can be rationally rejected. Even if ADH is augmented with causal information sufficient to account for the coherence and order of conscious experience, the resulting dream scepticism would then reduce to a BIV-type scepticism and thus fail to possess independent sceptical force. (shrink)

I am aware of the rain outside, but only in virtue of looking at a weather report. I am aware of my friend, but only because I hear her voice through my phone. Thus, there are some things that I’m aware of, but only indirectly. Many philosophers believe that there are also some things of which I am directly aware. The most plausible candidates are experiences such as pains, tickles, visual sensations, etc. In fact, the philosophical consensus seems to be (...) that experiences are the only plausible candidates for acquaintance. But I will argue that we are also acquainted with ourselves. After outlining what it means to be acquainted with oneself, I will introduce, develop, and defend a commonly used test for acquaintance. Then I will apply this test to us and show that we pass. I will consider various objections to my argument. But ultimately I will conclude that we can be, and often are, acquainted with ourselves. (shrink)

Bertrand Russell [1912] argued that we are acquainted with our experiences. Although this conclusion has generated a lot of discussion, very little has been said about Russell's actual arguments for it. This paper aims to remedy that. I start by spelling out two Russellian arguments for acquaintance. Then I show that these arguments cannot both succeed. For if one is sound, the other isn't. Finally, I weigh our options with respect to these arguments, and defend one option in particular. I (...) argue that we have good reason to believe that we can be, and sometimes are, acquainted with our experiences. (shrink)

To be acquainted with something (in the philosophical sense of “acquainted” discussed here) is to be directly aware of it. The idea that we are acquainted with certain things we experience has been discussed throughout the history of Western Philosophy, but in the early 20th century it gained especially focused attention among analytic philosophers who drew their inspiration from Bertrand Russell's work on acquaintance. Since then, many philosophers—particularly those working on self‐knowledge or perception—have used the notion of acquaintance to explain (...) various facts about human experience and knowledge. In this paper, I offer an overview of this work, with particular focus on the resurgent literature on acquaintance in contemporary analytic philosophy. After more fully explaining what acquaintance is (or is supposed to be), I describe some reasons for thinking that we are indeed acquainted with certain things we experience, and then I survey some of the facts about experience and knowledge that acquaintance may help explain. (shrink)

In this paper, we shall describe and critically evaluate four contemporary theories which attempt to solve the problem of the infinite regress of reasons: BonJour's ‘impure’ coherentism, BonJour's foundationalism, Haack's ‘foundherentism’ and Dancy's pure coherentism. These theories are initially put forward as theories about the justification of our empirical beliefs; however, in fact they also attempt to provide a successful response to the question of their own ‘metajustification.’ Yet, it will be argued that 1) none of the examined theories is (...) successful as a theory of justification of our empirical beliefs, and that 2) they also fall short of being adequate theories of metajustification. It will be further suggested that the failure of these views on justification is not coincidental, but is actually a consequence of deeper and tacitly held problematic epistemological assumptions (namely, the requirements of justificatory generality and epistemic priority), whose acceptance paves the way towards a generalized scepticism about empirical justification. (shrink)

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)

William Alston has been a long-time critic of the arguments of Wilfrid Sellars, and he has recently revisited the arguments made by Sellars in “Empiricism and the Philosophy of Mind.” Alston’s work attempts to show how Sellarsian views fail to account for our understanding of perception by making a two-part attack on Sellars’s account: part one of the attack takes up the Sellarsian approach to ‘looks’-talk, and part two concerns Sellars’s thoroughgoing conceptualism with regard to perception. In this article, I (...) argue that there is much in Alston’s view that does violence to our understanding of theoretical and practical reason by removing concepts (and thereby constraint by norms) from perception, and I show that Alston’s two-pronged attack fails due to its inadequate reading of “Empiricism and the Philosophy of Mind” and its problematic underlying epistemology. (shrink)

This paper argues that there is a problem for the justificatory significance of perceptions that has been overlooked thus far. Assuming that perceptual experiences are propositional attitudes and that only propositional attitudes which assertively represent the world can function as justifiers, the problem consists in specifying what it means for a propositional attitude to assertively represent the world without losing the justificatory significance of perceptions—a challenge that is harder to meet than might first be thought. That there is such a (...) problem can be seen by reconsidering and modifying a well-known argument to the conclusion that beliefs cannot be justified by perceptions but only by other beliefs. Nevertheless, the aim of the paper is not to conclude that perceptions are actually incapable of justifying our beliefs but rather to highlight an overlooked problem that needs to be solved in order to properly understand the justificatory relationship between perceptions and beliefs. (shrink)

In this paper, I show the complementarity of foundationalism and coherentism with respect to any efficient system of beliefs by means of a distinction between two types of proposition drawn from an analogy with an axiomatic system. This distinction is based on the way a given proposition is acknowledged as true, either by declaration (F-proposition) or by preservation (C-proposition). Within such a perspective, i.e., epistemological complementarism, not only can one see how the usual opposition between foundationalism and coherentism is irrelevant, (...) but furthermore one can appreciate the reciprocal relation between these two theories as they refer to two separate epistemological functions involved in the dynamics of constituting and expanding an epistemic system. (shrink)

When it comes to epistemic normativity, should we take the good to be prior to the right? That is, should we ground facts about what we ought and ought not believe on a given occasion in facts about the value of being in certain cognitive states (such as, for example, the value of having true beliefs)? The overwhelming answer among contemporary epistemologists is “Yes, we should.” This essay argues to the contrary. Just as taking the good to be prior to (...) the right in ethics often leads one to sanction implausible trade-offs when determining what an agent should do, so too, this essay argues, taking the good to be prior to the right in epistemology leads one to sanction implausible trade-offs when determining what a subject should believe. Epistemic value—and, by extension, epistemic goals—are not the explanatory foundation upon which all other normative notions in epistemology rest. (shrink)

Abductivists claim that explanatory considerations (e.g., simplicity, parsimony, explanatory breadth, etc.) favor belief in the external world over skeptical hypotheses involving evil demons and brains in vats. After showing how most versions of abductivism succumb fairly easily to obvious and fatal objections, I explain how rationalist versions of abductivism can avoid these difficulties. I then discuss the most pressing challenges facing abductivist appeals to the a priori and offer suggestions on how to overcome them.

I reconstruct and critique two arguments Laurence BonJour has recently offered against skepticism about the a priori. While the arguments may provide anti-skeptical, internalist foundationalists with reason to accept the a priori, I show that neither argument provides sufficient reason for believing the more general conclusion that there is no rational alternative to accepting the a priori.

The abductivist reply to skepticism is the view that commonsense explanations of the patterns and regularities that appear in our sensory experiences should be rationally preferred to skeptical explanations of those same patterns and regularities on the basis of explanatory considerations. In this article I critically examine Laurence BonJour’s rationalist version of the abductivist position. After explaining why BonJour’s account is more defensible than other versions of the view, I argue that the notion of probability he relies upon is deeply (...) problematic, that he incorporates an implausible double-standard concerning a priori and a posteriori justification, and that his view is vulnerable to skepticism about the a priori. I suggest that some of these problems are due to idiosyncratic commitments BonJour makes and that abductivists would be better off without them. I conclude with some suggestions about how to improve BonJour’s abductivist response to skepticism. (shrink)

In this paper I argue that Cartesian skepticism about the external world is self-defeating. The Cartesian skeptic holds that we are not justified in believing claims about the external world on the grounds that we cannot rule out the possibility of our being in a radical skeptical scenario. My argument against this position builds upon a critique of Wilson in Analysis, 72, 668–673. Wilson argues that the Cartesian’s skeptical reasoning commits him to mental state skepticism and that this undermines his (...) ability to claim that he is truly skeptical about the external world. I show that Wilson’s argument does not succeed. She is correct that the Cartesian is committed to mental state skepticism. However, she is mistaken in thinking that there is anything incoherent about combining the Cartesian position that one ought to doubt external world claims with doubt about whether one is in fact such a skeptic. I propose an alternative explanation as to why mental state skepticism proves to be the Cartesian’s undoing. I suggest that mental state skepticism leads to epistemic skepticism and that this undermines the Cartesian’s position that belief about the external world is unjustified. (shrink)

Pragmatism, Experience, and the Given The doctrine of the Given is that subjects have direct non-inferential awareness of content of their experiences and apprehensions, and that some of a subject's beliefs are justified on the basis of that subject's awareness of her experiences and apprehensions. Pragmatist criticisms of the Given as a myth are shown here not only to be inadequate but to presuppose the Given. A model for a pragmatist account of the Given is then provided in terms of (...) refinements of Dewey's theory of experience. The doctrine of the Given is implicated in the functions of inquiry insofar as one must take it that experience is a source of justification. (shrink)

John Cook Wilson (1849–1915) was Wykeham Professor of Logic at New College, Oxford and the founder of ‘Oxford Realism’, a philosophical movement that flourished at Oxford during the first decades of the 20th century. Although trained as a classicist and a mathematician, his most important contribution was to the theory of knowledge, where he argued that knowledge is factive and not definable in terms of belief, and he criticized ‘hybrid’ and ‘externalist’ accounts. He also argued for direct realism in perception, (...) criticizing both empiricism and idealism, and argued for a moderate nominalist view of universals as being in rebus and only ‘apprehended’ by their particulars. His influence helped swaying Oxford away from idealism and, through figures such as H. A. Prichard, Gilbert Ryle, or J. L. Austin, his ideas were also to some extent at the origin of ‘moral intuitionism’ and ‘ordinary language philosophy’ which defined much of Oxford philosophy until the second half of the twentieth-century. Nevertheless, his name and legacy were all but forgotten for generations after World War II. Still, his views on knowledge are with us today, being in part at work in the writings of philosophers as diverse as John McDowell, Charles Travis, and Timothy Williamson. (shrink)

In this paper we set out a view on which internalist proper basicality is secured by sensory experience.

One of the important discussions in the philosophy of mathematics, is that centered on Benacerraf’s Dilemma. Benacerraf’s dilemma challenges theorists to provide an epistemology and semantics for mathematics, based on their favourite ontology. This challenge is the point on which all philosophies of mathematics are judged, and clarifying how we might acquire mathematical knowledge is one of the main occupations of philosophers of mathematics. In this thesis I argue that this discussion has overlooked an important part of mathematics, namely mathematics (...) as it is exercised by ordinary people. I do so by looking at the different theories that have been put forward in the recent debate, and showing for each of these that they are unable to account for the mathematical practices of ordinary people. In order to show that these practices do need to be accounted for, I also argue that ordinary people are doing mathematics, i.e. that they engage in properly mathematical practices. Because these practices are properly mathematical, they should be accounted for by any philosophy of mathematics. The conclusion of my thesis, then, is that current theories fail to do something that they should do, while remaining neutral on how well they perform when it comes to accounting for the practices of professional mathematicians. (shrink)

El objetivo de este artículo es proponer una alternativa antiindividualista para el evidencialismo. Dicha alternativa sostiene que los estados doxásticos se constituyen en evidencias a partir de la aceptación de la comunidad epistémica en la que se presentan. En primer lugar, se explica qué problemas surgen cuando se intenta vincular al fiabilismo con la convicción propia de la evidencia. En segundo lugar, se sugiere que tales problemas pueden solucionarse si el evidencialismo incluye la idea de que los estándares de evaluación (...) de la comunidad epistémica determinan lo que puede ser una evidencia. Por último, se intenta tanto resaltar las virtudes como fijar el alcance del evidencialismo antiindividualista. The aim of this paper is to propose an anti-individualistic alternative to evidentialism. This alternative maintains that doxastic states constitute themselves as evidences on the basis of the acceptance of the epistemic community in which they arise. In the first place, the paper explains the problems that emerge when trying to link fiabilism to the conviction of evidence. In the second place, it suggests that those problems could be solved if evidentialism includes the idea that evaluation standards of the epistemic community establish what is evidence or not. Finally, it emphasizes the virtues of anti-individualistic evidentialism and seeks to determine its extent. (shrink)

In this dissertation I consider the problem of external world skepticism and attempts at providing an argument to the best explanation against it. In chapter one I consider several different ways of formulating the crucial skeptical argument, settling on an argument that centers on the question of whether we're justified in believing propositions about the external world. I then consider and reject several options for getting around this issue which I take to be inadequate. I finally conclude that the best (...) option available to us at the moment is to argue that the antiskeptical view is the best explanation of our ordinary experiences In chapter two I argue that, if we hope to ground what counts as defending antiskepticism in common sense, there is an argument against the possibility of ever knowing one has succeeded in defending antiskepticism. After showing that common sense is no place to look in setting a goal for our antiskeptical project, I present the view that what will be crucial to settling on our antiskeptical goal is coming to a successful analysis of the nature of physical objects. I suggest some minimal criteria that must be met by a view in order to be antiskeptical based on our intuitions about core skeptical cases, but acknowledge that a fully successful response to external world skepticism will require the antiskeptic to engage in some much more difficult analysis. In chapter three I consider various views of the nature of explanation and conclude, tentatively, that explanation as it interests the antiskeptic is fundamentally causal. In chapter four I consider and reject some of the core views on which best explanation facts are so fundamental that a project of attempting to vindicate probabilistically the virtues which make explanations epistemically good. In this chapter I show that views which analyze justification in terms of best explanation factors fail. In chapter five I attempt to vindicate the various explanatory virtues probabilistically. In doing so I attempt to express or translate the various explanatory virtues in terms of probabilities in order to show that having those virtues makes a view at least prima facie more probable. In chapters six and seven I explain and evaluate the various arguments to the best explanation against skepticism present in current philosophical literature. I attempt to show that extant arguments fail to appreciate the virtues possessed by classical skeptical scenarios. In chapter eight I briefly consider some options that may be open to the antiskeptic moving forward. All routes forward contain considerable obstacles, but there are some fruitful areas of research to pursue. (shrink)