The principle of epistemic closure is the claim that what is known to follow from knowledge is known to be true. This intuitively plausible idea is endorsed by a vast majority of knowledge theorists. There are significant problems, however, that have to be addressed if epistemic closure – closed knowledge – is endorsed. The present essay locates the problem for closed knowledge in the separation it imposes between knowledge and evidence. Although it might appear that all that stands between knowing (...) the truth of the premises of a valid inference and knowledge of its conclusion is inferring it from the premises, the evidence for each of the premises may jointly count against the conclusion. The intuitive view regarding inferred knowledge says one thing, the evidence says another. One epistemological framework that seems to have the resources to resolve this tension endorses the view that knowledge always requires conclusive evidence. A second framework resolves the tension by limiting the scope of the closure principle. Only inferences drawn directly from propositions contained in the scope of a single knowledge operator are considered closed. The aim of the present essay is to revive the unpopular third option, the idea that knowledge is open. The essay proceeds by arguing that in different ways the two former frameworks only succeed in relocating the problem, not in resolving it. The first framework, the infallibilist view, relocates the problem to a sharp separation between knowledge of the occurrences of events from knowledge of their chance of occurring, a separation leading to several significant additional problems. The fallibilist view, the second framework, in endorsing closure neglects to take into full account the ways in which evidence fails to be transitive. For instance, evidence can count in favor of a conjunction while counting against each of its conjuncts. This fact, which is argued for in the essay on probabilistic as well as non-probabilistic grounds, is used as the foundation of an argument against closed knowledge that can be used as a way to understand several of the most fundamental challenges of epistemology. Not only can an open knowledge view that is based on open evidence resolve all these problems in a simple and natural way, it can also respond to formidable challenges that significantly hinder other open knowledge views. There are good reasons, then, to view both knowledge and evidence as open. (shrink)

Deduction is important to scientific inquiry because it can extend knowledge efficiently, bypassing the need to investigate everything directly. The existence of closure failure—where one knows the premises and that the premises imply the conclusion but nevertheless does not know the conclusion—is a problem because it threatens this usage. It means that we cannot trust deduction for gaining new knowledge unless we can identify such cases ahead of time so as to avoid them. For philosophically engineered examples we have “inner (...) alarm bells” to detect closure failure, but in scientific investigation we would want to use deduction for extension of our knowledge to matters we don’t already know that we couldn’t know. Through a quantitative treatment of how fast probabilistic sensitivity is lost over steps of deduction, I identify a condition that guarantees that the growth of potential error will be gradual; thus, dramatic closure failure is avoided. Whether the condition is fulfilled is often obvious, but sometimes it requires substantive investigation. I illustrate that not only safe deduction but the discovery of dramatic closure failures can lead to scientific advances. (shrink)

It is argued, on the basis of new counterexamples, that neither knowledge nor epistemic justification (or “epistemic rationality”) can reasonably be thought to be closed under logical implication. The argument includes an attempt to reconcile the fundamental intuitions of the opposing parties in the debate.

Dretske's conclusive reasons account of knowledge is designed to explain how epistemic closure can fail when the evidence for a belief does not transmit to some of that belief's logical consequences. Critics of Dretske dispute the argument against closure while joining Dretske in writing off transmission. This paper shows that, in the most widely accepted system for counterfactual logic , conclusive reasons are governed by an informative, non-trivial, logical transmission principle. If r is a conclusive reason for believing p in (...) Dretske's sense, and if p logically implies q, and if p and q satisfy one additional condition, it follows that r is a conclusive reason for believing q. After introducing this additional condition, I explain its intuitive import and use the condition to shed new light on Dretske's response to scepticism, as well as on his distinction between the so-called ‘lightweight’ and ‘heavyweight’ implications of a piece of perceptual knowledge. (shrink)

In the contemporary expanding literature on transmission failure and its connections with issues such as the Closure principle, the nature of perceptual warrant, Moore’s proof of an external world and the effectiveness of Humean scepticism, it has often been assumed that there is just one kind of it: the one made familiar by the writings of Crispin Wright and Martin Davies. Although it might be thought that one kind of failure is more than enough, Davies has recently challenged this view: (...) apparently, there are more ways in heaven and earth that warrant can fail to transmit across valid inference from one (set of) belief(s) to another, than have been dreamt of in philosophy so far. More specifically, Davies thinks that a second kind of transmission failure has to be countenanced. He connects each kind of failure of transmission of warrant with two different kinds of epistemic project, respectively, and with the exploration of whether the current dispute between conservatives such as Wright, and liberals such as Jim Pryor, on the nature of perceptual warrant, would have a bearing on them. I point out why Davies’s second kind of transmission failure is indeed no such thing. I then move on to canvass another kind of transmission failure, different from the one studied by both Wright and Davies, and dependent on an alternative conception of the structure of empirical warrants, which I dub “moderatism”. I then consider how this alternative notion of transmission failure fares with respect to Moore’s proof, its relationship with Wright’s kind of transmission failure and with the Closure principle. In closing, I defend it from criticisms that can be elicited from Pryor’s recent work. (shrink)

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

It is argued, on the basis of new counterexamples, that neither knowledge nor epistemic justification (or epistemic rationality ) can reasonably be thought to be closed under logical implication. The argument includes an attempt to reconcile the fundamental intuitions of the opposing parties in the debate.

A very natural view about perceptual knowledge is articulated, one on which perceptual knowledge is closely related to perceptual discrimination, and which fits well with a relevant alternatives account of knowledge. It is shown that this kind of proposal faces a problem, and various options for resolving this difficulty are explored. In light of this discussion, a two-tiered relevant alternatives account of perceptual knowledge is offered which avoids the closure problem. It is further shown how this proposal can: accommodate our (...) intuitions about perceptual knowledge and perceptual discrimination in terms of the notion of primary relevance, give an account of how alternatives can be rationally excluded without appeal to perceptual discrimination in terms of the notion of secondary relevance, and deal with the problem posed by inverted Gettier cases, and hence explain what it means to rationally exclude alternatives which are of secondary relevance. (shrink)

Christoph Jäger has argued that Dretske’s information-based account of knowledge is committed to both knowledge and information closure under known entailment. However, in a reply to Jäger, Dretske defended his view on the basis of a discrepancy between the relation of information and the relation of logical implication. This paper shares Jäger’s criticism that Dretske’s externalist notion of information implies closure, but provides an analysis based on different grounds. By means of a distinction between two perspectives, the mathematical perspective and (...) the epistemological perspective, I present, in the former, a notion of logical implication that is compatible with the notion of information in the mathematical theory of information, and I show how, in the latter, Dretske’s logical reading of the closure principle is incompatible with his information-theoretic epistemological framework. (shrink)

Saul Kripke argued that the requirement that knowledge eliminate all possibilities of error leads to dogmatism . According to this view, the dogmatism puzzle arises because of a requirement on knowledge that is too strong. The paper argues that dogmatism can be avoided even if we hold on to the strong requirement on knowledge. I show how the argument for dogmatism can be blocked and I argue that the only other approach to the puzzle in the literature is mistaken.

It is widely thought that if knowledge requires sensitivity, knowledge is not closed because sensitivity is not closed. This paper argues that there is no valid argument from sensitivity failure to non-closure of knowledge. Sensitivity does not imply non-closure of knowledge. Closure considerations cannot be used to adjudicate between safety and sensitivity accounts of knowledge.

The possibility of knowledge attributions across contexts (where attributor and subject find themselves in different epistemic contexts) can create serious problems for certain views of knowledge. Amongst such views is subject—sensitive invariantism—the view that knowledge is determined not only by epistemic factors (belief, truth, evidence, etc.) but also by non—epistemic factors (practical interests, etc.). I argue that subject—sensitive invariantism either runs into a contradiction or has to make very implausible assumptions. The problem has been very much neglected but is so (...) serious that one should look for alternative accounts of knowledge. (shrink)

According to Duncan Pritchard, there are two kinds of radical sceptical problem; the closure-based problem, and the underdetermination-based problem. He argues that distinguishing these two problems leads to a set of desiderata for an anti-sceptical response, and that the way to meet all of these desiderata is by supplementing a form of Wittgensteinian contextualism with disjunctivist views about factivity. I agree that an adequate response should meet most of the initial desiderata Pritchard puts forward, and that some version of Wittgensteinian (...) contextualism shows the most promise as a starting point for this, but I argue, contra Pritchard, that the addition of disjunctivism is unnecessary and potentially counter-productive. If we draw on lessons from Michael Williams's inferential contextualism then it is both possible, and preferable, to meet the most important of Pritchard's desiderata, undercutting both closure-based and underdetermination-based sceptical problems in a unified way, without the need to resort to disjunctivism. (shrink)

We describe a general logical framework, Justification Logic, for reasoning about epistemic justification. Justification Logic is based on classical propositional logic augmented by justification assertions t: F that read t is a justification for F. Justification Logic absorbs basic principles originating from both mainstream epistemology and the mathematical theory of proofs. It contributes to the studies of the well-known Justified True Belief vs. Knowledge problem. We state a general Correspondence Theorem showing that behind each epistemic modal logic, there is a (...) robust system of justifications. This renders a new, evidence-based foundation for epistemic logic. As a case study, we offer a resolution of the GoldmanRed Barns in Justification Logic. Furthermore, we formalize the well-known Gettier example and reveal hidden assumptions and redundancies in Gettier’s reasoning. (shrink)

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

Knowledge closure is, roughly, the following claim: For every agent S and propositions P and Q, if S knows P, knows that P implies Q, and believes Q because it is so implied, then S knows Q. Almost every epistemologist believes that closure is true. Indeed, they often believe that it so obviously true that any theory implying its denial is thereby refuted. Some prominent epistemologists have nevertheless denied it, most famously Fred Dretske and Robert Nozick. There are closure advocates (...) who see other virtues in those accounts, however, and so who introduce revisions of one sort or another in order to preserve closure while maintaining their spirit. One popular approach is to replace the “sensitivity” constraint at the heart of both of those accounts with a “safety” constraint, as advocated by Timothy Williamson, Duncan Pritchard, Ernest Sosa, Stephen Luper, and others. The purpose of this essay is to show that this approach does not succeed: safety does not save closure. And neither does a popular variation on the safety theme, the safe-basis or safe-indicator account. (shrink)

Those of us who have followed Fred Dretske's lead with regard to epistemic closure and its impact on skepticism have been half-wrong for the last four decades. But those who have opposed our Dretskean stance, contextualists in particular, have been just wrong. We have been half-right. Dretske rightly claimed that epistemic status is not closed under logical implication. Unlike the Dretskean cases, the new counterexamples to closure offered here render every form of contextualist pro-closure maneuvering useless. But there is a (...) way of going wrong under Dretske's lead. As the paper argues, Cartesian skepticism thrives on closure failure in a way that is yet to be acknowledged in the literature. The skeptic can make do with principles which are weaker than the familiar closure principles. But I will further claim that this is only a momentary reprieve for the skeptic. As it turns out, one of the weaker principles on which a skeptical modus tollens must rest can be shown false. (shrink)

A critique of conversational epistemic contextualism focusing initially on why pragmatic encroachment for knowledge is to be avoided. The data for pragmatic encroachment by way of greater costs of error and the complementary means to raise standards of introducing counter-possibilities are argued to be accountable for by prudence, fallibility and pragmatics. This theme is sharpened by a contrast in recommendations: holding a number of factors constant, when allegedly higher standards for knowing hold, invariantists still recommend assertion (action), while contextualists do (...) not. Given the knowledge norm of assertion, if one recommendation is preferable to the other, the result favors the preferred recommendation's account of knowledge. In the final section, I offer a unification of these criticisms centering on the contextualist use of 'epistemic position'. Their use imposes on threshold notions of justification, warrant, or knowledge tests that are suitable only to unlimited comparative or scalar notions like confidence or certainty and places them at one with an important strand of sceptical reasoning. (shrink)

Tracking theories of knowledge are widely known to have the consequence that knowledge is not closed. Recent arguments by Vogel and Hawthorne claim both that there are no legitimate examples of knowledge without closure and that the costs of theories that deny closure are too great. This paper considers the tracking theories of Dretske and Nozick and the arguments by Vogel and Hawthorne. We reject the arguments of Vogel and Hawthorne and evaluate the costs of closure denial for tracking theories (...) of knowledge. (shrink)

Abstract: Luciano Floridi has impressively applied the concept of information to problems in semantics and epistemology, among other areas. In this essay, I briefly review two areas where I think one may usefully raise questions about some of Floridi's conclusions. One area is in the project to naturalize semantics and Floridi's use of the derived versus nonderived notion of semantic content. The other area is in the logic of information and knowledge and whether knowledge based on information necessarily supports closure, (...) in every instance. I suggest that it does not and, thereby, raise a challenge to Floridi's logic of being informed. (shrink)

Sven Bernecker develops a theory of propositional memory that is at odds with the received epistemic theory of memory. On Bernecker’s account the belief that is remembered must be true, but it need not constitute knowledge, nor even have been true at the time it was acquired. I examine his reasons for thinking the epistemic theory of memory is false and mount a defense of the epistemic theory.

This book offers a defence of Wrightean epistemic entitlement, one of the most prominent approaches to hinge epistemology. It also systematically explores the connections between virtue epistemology and hinge epistemology. -/- According to hinge epistemology, any human belief set is built within and upon a framework of pre-evidential propositions – hinges – that cannot be justified. Epistemic entitlement argues that we are entitled to trust our hinges. But there remains a problem. Entitlement is inherently unconstrained and arbitrary: We can be (...) entitled to any hinge proposition under the right circumstances. In this book, the author argues that we need a non-arbitrariness clause that protects entitlement from defeat. This clause, he argues, is to require epistemic virtue. Virtuous cognitive dispositions provide the non-arbitrariness clause that protects entitlement from defeat. The epistemic character of the agent who holds a particular set of hinges tells us something about the hinges’ epistemic status. Conversely, epistemic virtues are cognitive dispositions and capacities that rely on hinge propositions – without trusting in some hinges, we would be unable to exercise our virtues. -/- Trust Responsibly will appeal to scholars and advanced students working on epistemology, Wittgenstein, and virtues. (shrink)

In this paper I consider the prospects for pluralism about knowledge, that is, the view that there is a plurality of knowledge relations. After a brief overview of some views that entail a sort of pluralism about knowledge, I focus on a particular kind of knowledge pluralism I call standards pluralism. Put roughly, standards pluralism is the view that one never knows anything simpliciter. Rather, one knows by this-or-that epistemic standard. Because there is a plurality of epistemic standards, there is (...) a plurality of knowledge relations. In §1 I argue that one can construct an impressive case for standards pluralism. In §2 I clarify the relationship between standards pluralism, epistemic contextualism and epistemic relativism. In §3 I argue that standards pluralism faces a serious objection. The gist of the objection is that standards pluralism is incompatible with plausible claims about the normative role of knowledge. In §4 I finish by sketching the form that a standards pluralist response to this objection might take. (shrink)

Games, Norms, and Reasons: Logic at the Crossroads provides an overview of modern logic focusing on its relationships with other disciplines, including new interfaces with rational choice theory, epistemology, game theory and informatics. This book continues a series called "Logic at the Crossroads" whose title reflects a view that the deep insights from the classical phase of mathematical logic can form a harmonious mixture with a new, more ambitious research agenda of understanding and enhancing human reasoning and intelligent interaction. The (...) editors have gathered together articles from active authors in this new area that explore dynamic logical aspects of norms, reasons, preferences and beliefs in human agency, human interaction and groups. The book pays a special tribute to Professor Rohit Parikh, a pioneer in this movement. (shrink)

A Série Investigação Filosófica é uma série de livros de traduções de verbetes da Enciclopédia de Filosofia da Stanford (Stanford Encyclopedia of Philosophy) e de outras plataformas internacionalmente reconhecidas, que intenciona servir tanto como material didático para os professores das diferentes sub-áreas e níveis da Filosofia quanto como material de estudo para a pesquisa e para concursos da área. Nós, professores, sabemos o quão difícil é encontrar bom material em português para indicarmos. E há uma certa deficiência na graduação brasileira (...) de filosofia, principalmente em localizações menos favorecidas, com relação ao conhecimento de outras línguas, como o inglês e o francês. Tentamos, então, suprir essa deficiência, ao introduzirmos essas traduções ao público de língua portuguesa, sem nenhuma finalidade comercial e meramente pela glória da filosofia. (shrink)

An influential proposal is that knowledge involves safe belief. A belief is safe, in the relevant sense, just in case it is true in nearby metaphysically possible worlds. In this paper, I introduce a distinct but complementary notion of safety, understood in terms of epistemically possible worlds. The main aim, in doing so, is to add to the epistemologist’s tool-kit. To demonstrate the usefulness of the tool, I use it to advance and assess substantive proposals concerning knowledge and justification.

Sosa, Pritchard, and Vogel have all argued that there are cases in which one knows something inductively but does not believe it sensitively, and that sensitivity therefore cannot be necessary for knowledge. I defend sensitivity by showing that inductive knowledge is sensitive.

Crispin Wright’s “Unified Strategy” for addressing some familiar sceptical paradoxes exploits a subtle distinction between two different ways in which we can be related to a proposition: (full-blown) belief and (mere) acceptance. The importance of the distinction for his strategy stems from his conviction that we cannot acquire any kind of evidence, either empirical or a priori, for the “cornerstones” of our cognitive projects, i.e., for those basic presuppositions of our inquiries that we must be warranted to endorse if we (...) are to claim warrant for any of the beliefs formed as a result of such inquiries: regarding the idea of a non-evidential warrant to believe a proposition as a kind of “conceptual solecism”, he doesn’t set himself the task of showing that we are evidentially warranted to believe such presuppositions, but only that of showing that we are non-evidentially warranted to accept them. In the present paper, I argue that such choice involves a fatal departure from a basic principle governing doxastic commitment—a principle that requires that we regard cornerstones propositions as propositions we are rationally committed to believe, not just entitled to accept. I press the point by presenting the Acceptance Argument, a sceptical paradox whose consideration leads to the conclusion that the Unified Strategy is caught between the Scylla of incoherently invoking a rather dubious form of epistemic alchemy and the Charybdis of placing an unexpected and apparently ad hoc restriction on the doxastic commitments we undertake by believing the things we believe. My final suggestion is that the Unified Strategy might be spared this dilemma only by undergoing a rather radical revision—a revision that would require setting aside the distinction between belief and acceptance to re-conceptualise its goal unabashedly in terms of (non-evidentially) warranted belief. (shrink)

The conclusive reasons view of knowledge entails the “abominable conjunction” that I know that I have hands but I do not know that I am not a brain in a vat. The argument from abomination takes this as a reason to reject the view. This paper aims to buttress the argument from abomination by adding a new sort to this list: the logical abominations. These include: “I know that argument is sound and that sound arguments have true conclusions but I (...) don’t know whether the conclusion of that argument is true”. Two standard replies to the argument from abomination are raised. It is argued that the logical abominations open new holes in both. (shrink)

Dretske proposes a theory of knowledge in terms of a theory of information, but wishes to deny that empirical knowledge settles the large question of scepticism. This leads him to deny the closure of knowledge under known entailment. In a recent paper Jäger argues that Dretske's theory of information entails closure for knowledge, 'at least for the kind of propositions here at issue'. If Jäger is right, Dretske is seriously embarrassed and must give something up. In this paper I show (...) that there are two flaws in Jäger's argument. The principle of informational closure considered by Jäger is incompatible with Dretske's theory of information, and Jäger's argument that Dretske is committed to a certain kind of substitution instance of that principle of informational closure is invalid. I propose adequacy conditions on signalled information and use them to motivate a formulation of a general closure principle for signalled information. I show that Dretske's account of information satisfies the adequacy conditions, but in a way which commits him to an instance of the general closure principle. I argue that Dretske is consequently committed to closure for some cases of knowledge for which he wishes to deny closure. Finally, I sketch how, on the basis of the closure principle to which Dretske is committed, Jäger's broader argument may yet go through. (shrink)

The paper argues that knowledge is not closed under logical inference. The argument proceeds from the openness of evidential support and the dependence of empirical knowledge on evidence, to the conclusion that knowledge is open. Without attempting to provide a full-fledged theory of evidence, we show that on the modest assumption that evidence cannot support both a proposition and its negation, or, alternatively, that information that reduces the probability of a proposition cannot constitute evidence for its truth, the relation of (...) evidential support is not closed under known entailment. Therefore the evidence-for relation is deductively open regardless of whether evidence is probabilistic or not. Given even a weak dependence of empirical knowledge on evidence, we argue that empirical knowledge is also open. On this basis, we also respond to the strongest argument in support of knowledge closure. Finally, we present a number of significant benefits of our position, namely, offering a unified explanation for a range of epistemological puzzles. (shrink)

Skeptical theism - a strategy for dealing with so-called ‘evidential arguments from evil’ - is often held to lead to moral skepticism. In this paper I look at some of the responses open to the skeptical theist to the contention that her position leads to moral skepticism, and argue that they are ultimately unsuccessful, since they leave the skeptical theist with no grounds for ruling out the possibility of maximal divine deception. I then go on to argue that the situation (...) is particularly bleak for the skeptical theist, since the most prominent ways of dealing with this pervasive type of skepticism are not available to her. Furthermore, since this pervasive type of skepticism entails moral skepticism, it follows that moral skepticism will after all have found a way in ‘through the back door’. In order to solidify my case, I go on to outline and deal with three potential objections. (shrink)

This paper contributes to the current debate about radical scepticism and the structure of warrant. After a presentation of the standard version of the radical sceptic’s challenge, both in its barest and its more refined form, three anti-sceptical responses, and their respective commitments, are being identified: the Dogmatist response, the Conservativist response and the Dretskean response. It is then argued that both the Dretskean and the Conservativist are right that the anti-sceptical hypothesis cannot inherit any perceptual warrants from ordinary propositions (...) about the environment—and so the Dogmatist response founders. However, if this is so Epistemic Closure lacks any clear rationale. There is therefore good reason to agree with both the Dretskean and the Dogmatist that perceptual warrants for ordinary propositions about the environment are enough in order for those propositions to enjoy a positive epistemic status—and so the Conservativist response founders. However, the Conservativist is nonetheless right that a warrant for the anti-sceptical hypothesis is needed. For contrary to what much of the recent literature suggests, the radical sceptic need not appeal to Epistemic Closure in order to cast doubt on the legitimacy of our beliefs in ordinary propositions about the environment: there is a Pyrrhonian version of scepticism that, though equally radical, is consistent with failure of Epistemic Closure. For this reason, the Dretskean response is insufficient to answer scepticism. (shrink)

In this paper I deal with epistemological issues that stem from the hypothesis that reasoning is not only a means of transmitting knowledge from premise-beliefs to conclusion-beliefs, but also a primary source of knowledge in its own right. The idea is that one can gain new knowledge on the basis of suppositional reasoning. After making some preliminary distinctions, I argue that there are no good reasons to think that purported examples of knowledge grounded on pure reasoning are just examples of (...) premise-based inferences in disguise. Next, I establish what kinds of true propositions can to a first approximation be known on the basis of pure reasoning. Finally, I argue that beliefs that are competently formed on the basis of suppositional reasoning satisfy both externalist and internalist criteria of justification. (shrink)

I argue that while admission of one's own fallibility rationally requires one's readiness to stand corrected in the light of future evidence, it need have no consequences for one's present degrees of belief. In particular, I argue that one's fallibility in a given area gives one no reason to forego assigning credence 1 to propositions belonging to that area. I can thus be seen to take issue with David Christensen's recent claim that our fallibility has far-reaching consequences for our account (...) of rational belief and epistemic rationality. My arguments inter alia rely on the idea that in basing one's beliefs on one's evidence, one trusts both that one's evidence has the right pedigree and that one gets its probative force right, where such trust can rationally be invested without the need of any further evidence. (shrink)

I argue that coherence is truth-conducive in that coherence implies an increase in the probability of truth. Central to my argument is a certain principle for transitivity in probabilistic support. I then address a question concerning the truth-conduciveness of coherence as it relates to (something else I argue for) the truth-conduciveness of consistency, and consider how the truth-conduciveness of coherence bears on coherentist theories of justification.

It is well known that the probabilistic relation of confirmation is not transitive in that even if E confirms H1 and H1 confirms H2, E may not confirm H2. In this paper we distinguish four senses of confirmation and examine additional conditions under which confirmation in different senses becomes transitive. We conduct this examination both in the general case where H1 confirms H2 and in the special case where H1 also logically entails H2. Based on these analyses, we argue that (...) the Screening-Off Condition is the most important condition for transitivity in confirmation because of its generality and ease of application. We illustrate our point with the example of Moore’s “proof” of the existence of a material world, where H1 logically entails H2, the Screening-Off Condition holds, and confirmation in all four senses turns out to be transitive. (shrink)

It is well known that the probabilistic relation of confirmation is not transitive in that even if E confirms H1 and H1 confirms H2, E may not confirm H2. In this paper we distinguish four senses of confirmation and examine additional conditions under which confirmation in different senses becomes transitive. We conduct this examination both in the general case where H1 confirms H2 and in the special case where H1 also logically entails H2. Based on these analyses, we argue that (...) the Screening-Off Condition is the most important condition for transitivity in confirmation because of its generality and ease of application. We illustrate our point with the example of Moore’s ‘‘proof’’ of the existence of a material world, where H1 logically entails H2, the Screening-Off Condition holds, and confirmation in all four senses turns out to be transitive. (shrink)

Dretske is a “conciliatory skeptic” on self-knowledge. Take some subject S such that S thinks that P and S knows that she has thoughts. Dretske’s theory can be put as follows: S has a privileged way of knowing what she thinks, but she has no privileged way of knowing that she thinks it. There is much to be said on behalf of conciliatory skepticism and Dretske’s defense of it. We aim to show, however, that Dretske’s defense fails, in that if (...) his defense of CS’s skeptical half succeeds, then his defense of CS’s conciliatory half fails. We then suggest a potential way forward. We suggest in particular that the correct way of being a Dretskean conciliatory skeptic is to deny that S has a privileged way of knowing about her thoughts, but to grant that she is nonetheless an authority on her thoughts. (shrink)

Genia Schönbaumsfeld has recently argued for the view that our ordinary perceptual reasons provide support for heavyweight metaphysical and epistemological views, such as that there is a mind-independent physical world. Call this the Heavyweight Reasons Thesis. In this paper, I argue that we should reject the Heavyweight Reasons Thesis. I also argue that the rejection of the Heavyweight Reasons Thesis is compatible with the Factive Perceptual Reasons Thesis, the thesis that our perceptual reasons for our ordinary beliefs can be factive, (...) but that factive reasons aren’t necessarily better reasons than subjectively indiscriminable non-factive reasons. (shrink)

In his final notebooks, published as On Certainty , Wittgenstein offers a distinctive conception of the nature of reasons. Central to this conception is the idea that at the heart of our rational practices are essentially arational commitments. This proposal marks a powerful challenge to the standard picture of the structure of reasons. In particular, it has been thought that this account might offer us a resolution of the traditional scepticism/anti-scepticism debate. It is argued, however, that some standard ways of (...) filling out the details of this proposal ultimately lead to an epistemology which is highly problematic. The goal here is to present a more compelling version of Wittgenstein’s account of the structure of reasons which can evade these difficulties. (shrink)

This paper examines the relationship between perceptual knowledge and discrimination in the light of the so-called ‘relevant alternatives’ intuition. It begins by outlining an intuitive relevant alternatives account of perceptual knowledge which incorporates the insight that there is a close connection between perceptual knowledge and the possession of relevant discriminatory abilities. It is argued, however, that in order to resolve certain problems that face this view, it is essential to recognise an important distinction between favouring and discriminating epistemic support that (...) is often overlooked in the literature. This distinction complicates the story regarding how an alternative becomes relevant, and in doing so weakens the connection between perceptual knowledge and discrimination. The theory that results, however—what I term a ‘two-tiered’ relevant alternatives theory of perceptual knowledge—accommodates many of our intuitions about perceptual knowledge and so avoids the revisionism of some recent proposals in the epistemological literature. (shrink)

It is argued that it is beneficial to view the debate regarding radical scepticism through the lens of epistemic value. In particular, it is claimed that we should regard radical scepticism as aiming to deprive us of an epistemic standing that is of special value to us, and that this methodological constraint on our dealings with radical scepticism potentially has important ramifications for how we assess the success of an anti-sceptical strategy.

Support is canvassed for a novel solution to the sceptical problem regarding our knowledge of the external world. Key to this solution is the claim that what initially looks like a single problem is in fact two logically distinct problems. In particular, there are two putative sceptical paradoxes in play here, which each trade on distinctive epistemological theses. It is argued that the ideal solution to radical scepticism would thus be a biscopic proposal—viz., a two-pronged, integrated, undercutting treatment of both (...) putative sceptical paradoxes. A particular biscopic proposal is then explored which brings together two apparently opposing anti-sceptical theses: he Wittgensteinian account of the structure of rational evaluation and epistemological disjunctivism. It is argued that each proposal enables us to gain a purchase on one, but only one, aspect of the two-sided sceptical problem. Furthermore, it is argued that these proposals are not only compatible positions, but also mutually supporting and advanced in the same undercutting spirit. A potential cure is thus offered for epistemic angst. (shrink)

I offer a critical treatment of the contrastivist response to the problem of radical scepticism. In particular, I argue that if contrastivism is understood along externalist lines then it is unnecessary, while if it is understood along internalist lines then it is intellectually dissatisfying. Moreover, I claim that a closer examination of the conditions under which it is appropriate to claim knowledge reveals that we can accommodate many of the intuitions appealed to by contrastivists without having to opt for this (...) particular brand of epistemological revisionism. (shrink)

This paper considers two novel Bayesian responses to a well-known skeptical paradox. The paradox consists of three intuitions: first, given appropriate sense experience, we have justification for accepting the relevant proposition about the external world; second, we have justification for expanding the body of accepted propositions through known entailment; third, we do not have justification for accepting that we are not disembodied souls in an immaterial world deceived by an evil demon. The first response we consider rejects the third intuition (...) and proposes an explanation of why we have a faulty intuition. The second response, which we favor, accommodates all three intuitions; it reconciles the first and the third intuition by the dual component model of justification, and defends the second intuition by distinguishing two principles of epistemic closure. (shrink)