Modal metaphysics consumed much of the philosophical discussion at the turn of the century, yielding a number of epistemological insights. Modal analyses were applied within epistemology, yielding sensitivity and safety theories of knowledge as well as counterfactual accounts of the basing relation. The contemporary conversation has now turned to a new metaphysical notion – grounding – opening the way to a fresh wave of insights by bringing grounding into epistemology. In this paper, I attempt one such application, making sense of (...) the epistemic regress problem in terms of grounding. I argue that the relation that generates the epistemic regress is a grounding relation, showing that grounding can make sense of proposals by epistemic foundationalists and charting the course for similar applications to epistemic coherentism and epistemic infinitism. If it is right that grounding is involved in the epistemic regress, this points the way forward both for epistemologists and metaphysicians, revealing the prospects of solutions to the epistemic regress problem while providing grounding advocates with yet another example of grounding with which to theorize. (shrink)

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)

Several arguments attempt to show that if traditional, acquaintance-based epistemic internalism is true, we cannot have foundational justification for believing falsehoods. I examine some of those arguments and find them wanting. Nevertheless, an infallibilist position about foundational justification is highly plausible: prima facie, much more plausible than moderate foundationalism. I conclude with some remarks about the dialectical position we infallibilists find ourselves in with respect to arguing for our preferred view and some considerations regarding how infallibilists should develop their account (...) of infallible foundational justification. In particular, I provide an account of how propositions that moderate foundationalists claim are foundationally justified derive their epistemic support from infallibly known propositions. This is possible when a foundational proposition is coarsely-grained enough to correspond to determinable properties exemplified in experience or determinate properties that a subject insufficiently attends to; one may have inferential justification derived from such a basis when a more finely-grained proposition includes in its content one of the ways that the foundational proposition could be true. (shrink)

Properly understood, foundationalism as a meta‐epistemic theory is consistent with skepticism. This article outlines five possible points of overlap between the two views, and shows that arguments against foundationalism posited on its inability to refute skepticism are improperly framed.

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.

Richard Jeffrey developed the formula for probability kinematics with the intent that it would show that strong foundations are epistemologically unnecessary. But the reasons that support strong foundationalism are considerations of dynamics rather than kinematics. The strong foundationalist is concerned with the origin of epistemic force; showing how epistemic force is propagated therefore cannot undermine his position. The weakness of personalism is evident in the difficulty the personalist has in giving a principled answer to the question of when the conditions (...) for the application of the kinematic formula—the rigidity of the posteriors—are fulfilled, a problem made intractable by the personalist commitment to treating changes in intermediate probability as unexplained surds. Because the strong foundationalist admits changes in the intermediate probability of propositions only when there is some change in the foundations, he can avail himself of ananswer to the problem of the rigidity of the posteriors which the personalist cannot regard as complete. While probability kinematics does not make certain foundations unnecessary, the possession of certain foundations also does not make the probability kinematics formula superfluous. The formula allowsus to model the indirect routes by which the foundations influence various non-foundational propositions in the probability distribution. (shrink)

I offer an account of ad hocness that explains why the adoption of an ad hoc auxiliary is accompanied by the disconfirmation of a hypothesis H. H must be conjoined with an auxiliary a′, which is improbable antecedently given H, while ~H does not have this disability. This account renders it unnecessary to require, for identifying ad hocness, that either a′ or H have a posterior probability less than or equal to 0.5; there are also other reasons for abandoning that (...) condition. I distinguish between formal ad hocness, which is bad in the probabilistic sense that it results in disconfirmation of H, and argumentative ad hocness, which actually involves bad reasoning on the part of a subject. The latter is what I call “not counting the cost.” This distinction allows us to see why the 0.5 condition appeared attractive in the first place. The concept of not counting the cost also has implications for other areas of research, including both a Bayesian concept of unfalsifiability and the classic epistemological question of the problem of the external world. (shrink)

The phenomenon of mutual support presents a specific challenge to the foundationalist epistemologist: Is it possible to model mutual support accurately without using circles of evidential support? We argue that the appearance of loops of support arises from a failure to distinguish different synchronic lines of evidential force. The ban on loops should be clarified to exclude loops within any such line, and basing should be understood as taking place within lines of evidence. Uncertain propositions involved in mutual support relations (...) are conduits to each other of independent evidence originating ultimately in the foundations. We examine several putative examples of benign loops of support and show that, given the distinctions noted, they can be accurately modeled in a foundationalist fashion. We define an evidential "tangle," a relation among three propositions that appears to require a loop for modeling, and prove that all such tangles are trivial in a sense that precludes modeling them with an evidential circle. (shrink)

Several recent contextualist theorists have proposed contextualizing the skeptic. Their claim is that oneshould view satisfactory answers to global doubts regarding such subjects as theexternal world, other minds, and induction as requirements for justification incertain philosophical contexts, but not in everyday and scientific contexts. Incontrast, the skeptic claims that a satisfactory answer to a global doubt in eachof these areas is a context-invariant requirement for justified belief. In this paper,I consider and reject the arguments Michael Williams develops in his bookUnnatural (...) Doubts that are intended to show that the skeptic's interpretationof the significance of global doubts is mistaken. In addition, I argue that Williams'general strategy in opposing the skeptic is extremely interesting and worth furtherinvestigation, even if his particular execution of it is unsuccessful. To this end, Iclarify the general strategy, distinguish it from a variety of others, and discuss itsprospects as an answer to the skeptic. (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)

In “Compassionate Phenomenal Conservatism” (2007), “Phenomenal Conservatism and the Internalist Intuition” (2006), and Skepticism and the Veil of Perception (2001), Michael Huemer endorses the principle of phenomenal conservatism, according to which appearances or seemings constitute a fundamental source of (defeasible) justification for belief. He claims that those who deny phenomenal conservatism, including classical foundationalists, are in a self-defeating position, for their views cannot be both true and justified; that classical foundationalists have difficulty accommodating false introspective beliefs; and that phenomenal conservatism (...) is most faithful to the central internalist intuition. I argue that Huemer’s self-defeat argument fails, that classical foundationalism is able to accommodate fallible introspective beliefs, and that classical foundationalism captures a relatively clear internalist intuition. I also show that the motivation for phenomenal conservatism is less than clear. (shrink)

In Justification without Awareness (2006), Michael Bergmann presents a dilemma for internalism from which he claims there is “no escape”: The awareness allegedly required for justification is either strong awareness, which involves conceiving of some justification-contributor as relevant to the truth of a belief, or weak awareness, which does not. Bergmann argues that the former leads to an infinite regress of justifiers, while the latter conflicts with the “clearest and most compelling” motivation for endorsing internalism, namely, that for a belief (...) to be justified its truth must not be an accident from the subject’s perspective. Bergmann’s dilemma might initially seem to have the force of a knock-down argument against the classical foundationalist accounts he considers, if not against all forms of internalism. I argue, however, that the weak-awareness horn of Bergmann’s dilemma is unsuccessful. Classical foundationalists can hold on to the main motivation for internalism and avoid a vicious regress of justifiers. (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)

Religious epistemology is the study of how subjects' religious beliefs can have, or fail to have, some form of positive epistemic status and whether they even need such status appropriate to their kind. The current debate is focused most centrally upon the kind of basis upon which a religious believer can be rationally justified in holding certain beliefs about God and whether it is necessary to be so justified to believe as a religious believer ought. Engaging these issues are primarily (...) three groups of people who call themselves ‘fideists’, ‘Reformed epistemologists’, and ‘evidentialists’. Each group has a position, but the positions are not mutually exclusive in every case, and in the debate, the names better describe the groups' emphases than mutually exclusive positions in the debate. In this article, we will first give a brief historical survey of evidentialism, fideism, and reformed epistemology. Second, we will give the fideist's position. Third, we will give the evidentialist's position. Fourth, we will give the reformed epistemologist's position, and last, we will include some comments on the current state of the debate, where we will show that the groups' positions are not mutually exclusive. (shrink)

While there is no shortage of philosophical literature discussing knowledge by acquaintance, there is a surprising dearth of work about theories of epistemic justification based on direct acquaintance. This paper explores a basic framework for a thoroughly general account of epistemic justification by acquaintance. I argue that this approach to epistemic justification satisfies two importance aspects of justification. After sketching how the acquaintance approach can meet both objective and subjective aspects for epistemic justification, I will outline how this general account (...) of justification by acquaintance can be applied to the analysis of justification for many types of beliefs. Finally, some of the objections to the acquaintance approach will be considered and answered. (shrink)

By exploiting a concept called ways of believing, I offer a plausible reformulation of the doctrine of privileged access. This reformulation will provide us with a defense of compatibilism, the view that content externalism and privileged access are compatible.

What follows is a taxonomy of arguments that regresses of inferential justification are vicious. They fall out into four general classes: conceptual arguments from incompleteness, conceptual arguments from arbitrariness, ought-implies-can arguments from human quantitative incapacities, and ought-implies can arguments from human qualitative incapacities. They fail with a developed theory of "infinitism" consistent with valuational pluralism and modest epistemic foundationalism.

Epistemic infinitism is the view that infinite series of inferential relations are productive of epistemic justification. Peirce is explicitly infinitist in his early work, namely his 1868 series of articles. Further, Peirce's semiotic categories of firsts, seconds, and thirds favors a mixed theory of justification. The conclusion is that Peirce was an infinitist, and particularly, what I will term an impure infinitist. However, the prospects for Peirce's infinitism depend entirely on the prospects for Peirce's early semantics, which are not good. (...) Peirce himself revised the semantic theory later, and in so doing, it seems also his epistemic infinitism. (shrink)

I will assume here the defenses of epistemic infinitism are adequate and inquire as to the variety standpoints within the view. I will argue that infinitism has three varieties depending on the strength of demandingness of the infinitist requirement and the purity of its conception of epistemic justification, each of which I will term strong pure, strong impure, and weak impure infinitisms. Further, I will argue that impure infinitisms have the dialectical advantage.

Williamson’s anti-luminosity argument has been thought to be in tension with the doctrine that we enjoy privileged epistemic access to our own mental states. In this paper, I will argue that the tension is only apparent. Friends of privileged access who accept the conclusion of the argument need not give up the claim that our beliefs about our own mental states are mostly or invariably right, nor the view that mental states are epistemically available to us in a way that (...) renders everything within our mind ‘open to view’ – arguably, two main pillars of their doctrine. What they need to reject is the idea that the mental is a realm whose ’determinacy’ or ’fineness of grain’ never escapes our appreciation. This idea – I will suggest – is not essential to privileged access and defenders of the doctrine should not be afraid to give it up. (shrink)

Our beliefs utilize various sources: perception, memory, induction, etc. We trust these sources to provide reliable information about the world around us. My dissertation investigates how this trust could be justified. Chapter one introduces background material. I argue that justification rather than knowledge is of primary epistemological importance, discuss the internalism/externalism debate, and introduce an evidentialist thesis that provides a starting point/framework for epistemological theorizing. Chapter two introduces a puzzle concerning justification. Can a belief source provide justification absent prior justification (...) for believing it's reliable? Any answer appears to either make justifying the reliability of a source intellectually unsatisfying or all together impossible. Chapter three considers and rejects a plethora of proposed solutions to our puzzle. Investigating these solutions illustrates the need to further investigate evidence, evidence possession, and evidential support. Chapter four discusses the metaphysics of evidence. I argue that evidence always consists of a set of facts and that fact-proposition pairs stand in confirmation relations isomorphic to those holding between pairs of propositions. Chapter five argues that justification requires what I call actually connected possession of supporting evidence: a subject must be aware of supporting evidence and of the support relation itself. Chapter six argues that the relation constitutive of a set of facts being justificatory evidence is a sui generis and irreducible relation that is knowable a priori. Chapter seven begins by showing how Richard Fumerton's acquaintance theory meets the constraints on a theory of justification laid down in previous chapters. I modify the theory so as to: make room for fallible foundational justification, and allow inferential justification absent higher-order beliefs about evidential connections. Chapter eight applies the developed theory of justification to our initial puzzle. I show how my modified acquaintance theory is in a unique position to vindicate the idea that necessarily a source provides a person with justification only if she is aware of evidence for the reliability of that source. However, this awareness of evidence for a source's reliability falls short of a justified belief and thereby avoids impalement from our dilemma's skeptical horn. (shrink)

Traditional accounts of justification can be characterized as trying to analyze justification in such a way that having a justified belief brings with it assurance of truth. The internalist offers a demanding requirement on justification: one's having a justified belief requires that one see what the belief has going for it. Externalists worry that the internalist's narrow conception of justification will lead to unacceptably radical and implausible skepticism. According to the externalist, one need not know what a belief has going (...) for it in order for that belief to be justified. Externalism, though, comes with its own problems. Ernest Sosa has attempted to bridge the divide between internalism and externalism by pairing the strengths of internalism with the strengths of externalism. Sosa distinguishes two kinds of knowledge: animal knowledge that is essentially externalist in character and reflective knowledge that is intended to capture our best intellectual procedure in regards to knowledge. On Sosa's view, one gains reflective knowledge by building upon animal knowledge. As a result, Sosa's view seems to illustrate a bottom-up approach to the analysis of knowledge : reflective knowledge is the result of animal knowledge and some other epistemic factor. My project, in contrast to Sosa's, is to argue that one should start with an account of ideal justification and then proceed by loosening the standards on ideal justification in an effort to develop the possibility of non- ideal kinds of justification. The view that I will develop will adopt Sosa's strategy of distinguishing kinds of knowledge, but will result in a top-down approach to the analysis of justification. Instead of starting with an undemanding standard and layer levels on top, I will start with an ideal standard and strip layers away. I will also argue that my view has some important advantages over Sosa's. Not only does Sosa's view seem to run into many of the problems that threaten externalism, but his view is incapable of offering the kind of assurance that the internalist is after. The view I develop will maintain the internalist's interest in assurance while also providing a response to some of the skeptical problems that have plagued internalists. If my project is successful, then, even if the justification that results in many of the cases I will be exploring is not ideal, we can use these conceptions of justification to help explicate how one might have justified beliefs about a great number of things. The essentially internalist account that I have offered will not only illustrate a serious approach to dealing with skepticism, but it will also capture how many of our commonsensically justified beliefs are in fact justified. (shrink)

If political decision-making aims at getting a particular result, like identifying just laws or policies that truly promote the common good, then political institutions can also be evaluated in terms of how often they achieve these results. Epistemic defenses of democracy argue that democracies have the upper hand when it comes to truth, identifying the laws and policies that are truly just or conducive to the common good. A number of epistemic democrats claim that democracies have this beneficial connection to (...) truth because of the type of deliberative environment created by democratic political institutions. Democratic political cultures make it easier to exchange and give reasons, ultimately improving the justification that citizens have for their political beliefs. With this improved justification comes a better chance at truth, or so the story goes. In this paper, I show that attempts to forge a connection between justification and truth in epistemology have encountered numerous difficulties, making the case that this causes trouble for deliberative epistemic defenses of democracy as well. If there is no well-defined connection between truth and justification, then increasing the justification that citizens have for their beliefs may not also increase the likelihood that those beliefs are true, revealing a serious flaw in charting a connection between political justification and political truth. (shrink)

I argue that to know that a proposition is true one must have justification for being certain that the proposition is true. That is, one must have infallible epistemic justification for believing the proposition. It is widely accepted among epistemologists that we rarely, if ever, have such strong justification for our beliefs. It follows that there is precious little that we know. That conclusion is unacceptable to many philosophers. I argue that the positions that lead to the skeptical conclusion are (...) well-motivated and that the skeptical conclusion is implicitly accepted by ordinary speakers. My dissertation has three main components: a metaphilosophical position, an epistemological position, and an error theory. First, the metaphilosophical position. One very important part of philosophy is the analysis of our ordinary concepts. Analysis of our concepts begins with reflecting on what we are inclined to say about various actual and possible cases when considered under specific descriptions. This traditional method has recently come under attack, due in part to the rise of semantic externalism. I agree with externalists that if ‘meaning is reference’ then there is little reason to think reflecting on our concepts from the armchair will provide insight to the nature of the concepts we investigate. I defend a version of semantic internalism which grounds meaning in factors with which subjects are directly acquainted. That view supports the traditional methodology. Furthermore, as the goal of philosophical analysis is to accurately describe concepts of philosophical interest, the only kind of objection that could be decisive against a proposed analysis is that it does not correctly describe our concept. That opens the door to a skeptical analysis of knowledge. Second, the epistemological position. I argue that the unacceptability of sentences of the form “S knows that p but it is possible for S that not-p” is best explained by the hypothesis that our concept of knowledge requires having justification for being certain that what one believes is true. I offer as a criterion of justified certainty the idea that when one knows a proposition is true, one is in a position to decisively answer questions about one’s knowledge of that proposition. I survey a number of competing theories of knowledge and show that they allow for the possibility of knowledge when one fails my criterion of decisive answerability. Those views fail my criterion because according to those views there is nothing the subject is aware of that guarantees for the subject that the allegedly known proposition is true. On that basis, I contend that knowledge is direct awareness of the factors that constitute the truth of the proposition one believes. Third, the error theory. Of course, we rarely have direct awareness of the factors that constitute the truth of the propositions we believe. So, our knowledge attributions are generally false. Yet, they are overwhelmingly natural to make. I argue that competent speakers are often quick to recognize knowledge attributions as a kind of ‘loose talk’ akin to the way we loosely ascribe geometric properties to ordinary objects. We regularly call objects ‘square’ that are not even close to being square, and we are quick to recognize this when challenged. I argue that we do this because we are so accustomed to communicating using strict language to make false claims that we often do not attend to the literal falsity of what we are saying. While we accept very demanding standards for knowledge, the phenomenon of recognizing that our knowledge claims are regularly false is as pervasive as our use of loose speech. (shrink)

It is sometimes assumed in the Bayesian coherentist literature that the project of finding a truth-conducive measure of coherence of testimonial contents will, if successful, be helpful to the coherentist theory of justification. Various impossibility results in the Bayesian coherentist literature are consequently taken to be prima facie detrimental to the coherentist theory of justification. These attempts to connect Bayesian coherentism to the coherentist/ foundationalist debate in classical epistemology rest upon a confusion between the justification of a proposition and the (...) credibility that a proposition has for some other proposition. Foundationalism requires a class of beliefs that have non- inferential justification, not beliefs that have credibility by themselves for others. Coherentists insist that beliefs can be justified only via inferential relations with others, but this does not mean that coherentists must deny that individual propositions can have credibility for other propositions. I analyze and respond to both Erik Olsson's and Michael Huemer's arguments concerning the alleged connection between the Bayesian coherentist project and the coherentist theory of justification. Finally, I argue that Bayesian coherentism as represented in the literature, so far from being a version of coherentism, is implicitly foundationalist because of its treatment of “witness reports”, especially the reports of memory and sensation, as given evidence. The impossibility results, based on the assumption of given reports, are therefore not targeted at classical coherentism in epistemology at all. (shrink)

Many of our ordinary beliefs about the world around us are a result of inference from more fundamental beliefs. Foundationalists in epistemology have thought that, if these ordinary beliefs are to be rationally justified, the chain of inferential justification must terminate in a belief that is justified noninferentially. Foundationalists, of the internalist variety, have thought that the most plausible candidates for ending the regress of empirical justification are experiential states, the justifying features of which the believing subject is aware. The (...) Sellarsian dilemma, taking its name from philosopher Wilfrid Sellars, has been a persistent argument against foundationalist theories of epistemic justification. There have been various formulations of the dilemma over the years, but in its most general form it says that for any construal of an experiential state where the experiential state provides justification, the experiential state will need further justification. Sellars thought that an experience, all by itself, cannot provide justification unless we apply concepts to the experience. However, the application of concepts is judgmental and conceptual judgments, like beliefs, require further justification. So, the experiential state construed this way would perpetuate the regress it was designed to terminate. On the other hand, if the experiential state is construed such that it is not in need of justification, then it cannot itself provide justification. Both options are devastating to a foundationalist epistemology. My thesis is that a solution to all forms of the Sellarsian dilemma is to require for foundational justification direct awareness of the fit between one's conceptual judgment and the justifying experiential state. I concede that one must conceptualize one's experiential states for these states to play an epistemic role. However, I argue that conceptual judgments of this sort are the foundations. The importance of this solution is that it not only terminates the regress of justification but it also captures the primary intuitions that motivate internalism and foundationalism. This is to say that although I have framed my account as a response to the Sellarsian dilemma, it is not merely an ad hoc patch that avoids what stood as a serious problem. Instead, it is a return to what has motivated and what I take to be most persuasive about internalist foundationalism. (shrink)

Defenders of the Knowledge Argument contend that physicalism is false because knowing all the physical truths is not sufficient to know all the truths about the world. In particular, proponents of the Knowledge Argument claim that physicalism is false because the truths about the character of conscious experience are not knowable from the complete set of physical truths. This dissertation is a defense of the Knowledge Argument. Chapter one characterizes what physicalism is and provides support for the claim that if (...) knowing all the physical truths is not sufficient to know all the truths about the world, then physicalism is false. In chapter two, I defend the claim that knowing all the physical truths is not sufficient for knowing all the truths about the world. In addition to mounting a prima facie case for the knowledge intuition, I present and defend an epistemology grounded in direct acquaintance to provide a more substantive argument to accept it. Chapters three through five address the physicalist objections to the Knowledge Argument. The first set of objections advocates that knowing all the physical truths is, in fact, sufficient for knowing all the truths about the world. The next set of objections admits that there is some sense in which knowing all the physical truths is not sufficient for knowing all the truths about the world. However, these objections maintain that the kind of knowledge that is absent from the complete set of physical truths is know-how or knowledge by acquaintance, and not factual or propositional knowledge. The final set of objections maintain that the kind of propositional knowledge that is left out of the complete set of physical truths is compatible with physicalism. My response to these objections is part of advancing my prima facie case for the Knowledge Argument. The final chapter addresses a structural question that pertains to the Knowledge Argument. Some philosophers have maintained that the structure of the Knowledge Argument invites a kind of self-refutation of any systematic account of reality. The concern is that the Knowledge Argument proves too much, and that the dualist who uses the argument to refute physicalism risks the argument defeating his own position. I will argue that the Knowledge Argument does not refute dualism. (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)