Sometimes we get evidence of our own epistemic malfunction. This can come from finding out we’re fatigued, or have been drugged, or that other competent and well-informed thinkers disagree with our beliefs. This sort of evidence seems to seems to behave differently from ordinary evidence about the world. In particular, getting such evidence can put agents in a position where the most rational response involves violating some epistemic ideal.

It appears to have gone unnoticed in the literature that Pollock's widely endorsed analysis of evidential defeat entails a remarkably strong symmetry principle, according to which, for any three propositions D, E and H, if both E and D provide a reason to believe H, then D is a defeater for E's support for H if and only if, in turn, E is a defeater for D's support for H. After illustrating the counterintuitiveness of this constraint, a simple, more suitable, (...) alternative to the Pollockian account is offered. (shrink)

Scott Sturgeon has recently challenged Pollock’s account of undercutting defeaters. The challenge involves three primary contentions: the account is both too strong and too weak, undercutting defeaters exercise their power to defeat only in conjunction with higher-order beliefs about the basis of the lower-order beliefs whose justification they target, and since rebutting defeaters exercise their power to defeat in isolation, rebutting and undercutting defeaters work in fundamentally different ways. My goal is to reject each of these contentions. I maintain that (...) Sturgeon fails to show that Pollock’s account of undercutting defeaters is either too strong or too weak, his own account of how undercutting defeaters exercise their power to defeat is both too strong and too weak, and his claim that rebutting and undercutting defeaters work in fundamentally different ways is mistaken. (shrink)

Fallibilists claim that one can know a proposition on the basis of evidence that supports it even if the evidence doesn't guarantee its truth. Jessica Brown offers a compelling defence of this view against infallibilists, who claim that it is contradictory to claim to know and yet to admit the possibility of error.

Internalists tend to impose on justification higher-level requirements, according to which a belief is justified only if the subject has a higher-level belief (i.e., a belief about the epistemic credentials of a belief). I offer an error theory that explains the appeal of this requirement: analytically, a belief is not justified if we have a defeater for it, but contingently, it is often the case that to avoid having defeaters, our beliefs must satisfy a higher-level requirement. I respond to the (...) objection that externalists who endorse this error theory will be forced to accept a radical form of scepticism. (shrink)

One attractive feature of process reliabilism is its reductive potential: it promises to explain justification in entirely non-epistemic terms. In this paper, I argue that the phenomenon of epistemic defeat poses a serious challenge for process reliabilism’s reductive ambitions. The standard process reliabilist analysis of defeat is the ‘Alternative Reliable Process Account’ (ARP). According to ARP, whether S’s belief is defeated depends on whether S has certain reliable processes available to her which, if they had been used, would have resulted (...) in S not holding the belief in question. Unfortunately, ARP proves untenable. I show, by way of counterexample, that ARP fails to articulate either necessary or sufficient conditions on defeat. Process reliabilists must either provide an alternative reductive account of defeat or renounce their reductive aspirations. (shrink)

Elsewhere I and others have argued that evidence one should have had can bear on the justification of one's belief, in the form of defeating one's justification. In this paper, I am interested in knowing how evidence one should have had (on the one hand) and one's higher-order evidence (on the other) interact in determinations of the justification of belief. In doing so I aim to address two types of scenario that previous discussions have left open. In one type of (...) scenario, there is a clash between a subject's higher-order evidence and the evidence she should have had: S's higher-order evidence is misleading as to the existence or likely epistemic bearing of further evidence she should have. In the other, while there is further evidence S should have had, this evidence would only have offered additional support for S's belief that p. The picture I offer derives from two “epistemic ceiling” principles linking evidence to justification: one's justification for the belief that p can be no higher than it is on one's total evidence, nor can it be higher than what it would have been had one had all of the evidence one should have had. Together, these two principles entail what I call the doctrine of Epistemic Strict Liability: insofar as one fails to have evidence one should have had, one is epistemically answerable to that evidence whatever reasons one happened to have regarding the likely epistemic bearing of that evidence. I suggest that such a position can account for the battery of intuitions elicited in the full range of cases I will be considering. (shrink)

This new edition of the classic Contemporary Theories of Knowledge has been significantly updated to include analyses of the recent literature in epistemology.

In this paper, we propose a new theory of rationality defeat. We propose that defeaters are "indicators of ignorance", evidence that we’re not in a position to know some target proposition. When the evidence that we’re not in a position to know is sufficiently strong and the probability that we can know is too low, it is not rational to believe. We think that this account retains all the virtues of the more familiar approaches that characterise defeat in terms of (...) its connection to reasons to believe or to confirmation but provides a better approach to higher-order defeat. We also think that a strength of this proposal is that it can be embedded into a larger normative framework. On our account the no-defeater condition is redundant. We can extract our theory of defeat from our theory of what makes it rational to believe—it is rational to believe when it is sufficiently probable that our belief would be knowledge. Thus, our view can provide a monistic account of defeat, one that gives a unifying explanation of the toxicity of different defeaters that is grounded in a framework that either recognises knowledge as the norm of belief or identifies knowledge as the fundamental epistemic good that full belief can realise. (shrink)

Although there is disagreement about the details, John Pollock’s framework for defeat is now part of the received wisdom in analytic epistemology. Recently, however, cracks have appeared in the consensus, particularly on the understanding of undercutting defeat. While not questioning the existence of undercutting defeat, Scott Sturgeon argues that undercutting defeat operates differently from rebutting. Unlike the latter, undercutting defeat, Sturgeon claims, occurs only in conjunction with certain higher-order contributions, i.e., with beliefs about the basis on which one does or (...) would believe. Sturgeon concludes that Pollock misconceives undercutting defeat. I argue that in the case of defeat of inferential justification, undercutting defeat is a genuine phenomenon and takes roughly the shape Pollock suggests, not needing help from higher-order beliefs or justifications. However, I agree with Sturgeon that for noninferential justification the Pollockian account is in trouble. I try to explain why there should be this difference. This difference in defeaters has important implications for epistemology. In a final section, I use the defeat-related difference between inferential and noninferential justification to argue that there is less noninferential perceptual or testimonial justification than is commonly thought. (shrink)

This volume is about the notion of 'defeat' in philosophy. The idea is that someone who has some knowledge, or a justified belief, can lose this knowledge or justified belief if they acquire a 'defeater' - evidence that undermines it. The contributors examine the role of defeat not just in epistemology but in practical reasoning and ethics.

I defend interest-relative invariantism from a number of recent attacks. One common thread to my response is that interest-relative invariantism is a muchweaker thesis than is often acknowledged, and a number of the attacks only challenge very specific, and I think implausible, versions of it. Another is that a number of the attacks fail to acknowledge how many things we have independent reason to believe knowledge is sensitive to. Whether there is a defeater for someone's knowledge can be sensitive to (...) all manner of features of their environment, as the host of examples from the post-Gettier literature shows. Adding in interest-sensitive defeaters is a much less radical move than most critics claim it is. (shrink)

Princeton University Press, 1974. This book is out of print, but can be downloaded as a pdf file (5 MB).

Taking the inspiration from some points made by Scott Sturgeon and Albert Casullo, I articulate a view according to which an important difference between undermining and overriding defeaters is that the former require the subject to engage in some higher-order epistemic thinking, while the latter don’t. With the help of some examples, I argue that underminers push the cognizer to reflect on the way she formed a belief by challenging the epistemic worthiness of either the source of justification or the (...) specific justificatory process. By contrast, overriders needn’t pose any such challenge. I also consider some problems for the proposed view, and I put forward some possible solutions. Finally, I provide some details on how undermining defeat works in different cases. (shrink)

Recent authors have drawn attention to a new kind of defeating evidence commonly referred to as higher-order evidence. Such evidence works by inducing doubts that one’s doxastic state is the result of a flawed process – for instance, a process brought about by a reason-distorting drug. I argue that accommodating defeat by higher-order evidence requires a two-tiered theory of justification, and that the phenomenon gives rise to a puzzle. The puzzle is that at least in some situations involving higher-order defeaters (...) the correct epistemic rules issue conflicting recommendations. For instance, a subject ought to believe p, but she ought also to suspend judgment in p. I discuss three responses. The first resists the puzzle by arguing that there is only one correct epistemic rule, an Über-rule. The second accepts that there are genuine epistemic dilemmas. The third appeals to a hierarchy or ordering of correct epistemic rules. I spell out problems for all of these responses. I conclude that the right lesson to draw from the puzzle is that a state can be epistemically rational or justified even if one has what looks to be strong evidence to think that it is not. As such, the considerations put forth constitute a non question-begging argument for a kind of externalism. (shrink)

It is widely assumed that memory has only the capacity to preserve epistemic features that have been generated by other sources. Specifically, if S knows (justifiedly believes/rationally believes) that p via memory at T2, then it is argued that (i) S must have known (justifiedly believed/rationally believed) that p when it was originally acquired at Tl, and (ii) S must have acquired knowledge that p (justification with respect to p/rationality with respect to p) at Tl via a non-memorial source. Thus, (...) according to this view, memory cannot make an unknown proposition known, an unjustified belief justified, or an irrational belief rational--it can only preserve what is already known, justified, or rational. In this paper, I argue that condition (i) is false and, a fortiori, that condition (ii) is false. Hence, I show that, contrary to received wisdom in contemporary epistemology, memory can function as a generative epistemic source. (shrink)

Rich with historical and cultural value, these works are published unaltered from the original University of Minnesota Press editions.

The concept of evidence is central to both epistemology and the philosophy of science. Of course, ‘evidence’ is hardly a philosopher's term of art: it is not only, or even primarily, philosophers who routinely speak of evidence, but also lawyers and judges, historians and scientists, investigative journalists and reporters, as well as the members of numerous other professions and ordinary folk in the course of everyday life. The concept of evidence would thus seem to be on firmer pre-theoretical ground than (...) various other concepts which enjoy similarly central standing within philosophy. (Contrast, for example, the epistemologist's quasi-technical term ‘epistemic justification’.). (shrink)

Many views rely on the idea that it can never be rational to have high confidence in something like, “P, but my evidence doesn’t support P.” Call this idea the “Non-Akrasia Constraint”. Just as an akratic agent acts in a way she believes she ought not act, an epistemically akratic agent believes something that she believes is unsupported by her evidence. The Non-Akrasia Constraint says that ideally rational agents will never be epistemically akratic. In a number of recent papers, the (...) Non-Akrasia Constraint has been called into question. The goal of this paper is to defend it... for the most part. (shrink)

It is widely assumed that justification is defeasible, e.g. that under certain conditions counterevidence removes prior justification of beliefs. In this paper I will first (sect. 1) explain why this feature of justification poses a prima facie problem for reliabilism. I then will try out different reliabilist strategies to deal with the problem. Among them I will discuss conservative strategies (sect. 2), eliminativist stragies (sect. 3) and revisionist strategies (sect. 4). In the final section I will present an improved revisionist (...) approach to defeaters that is able to overcome the main shortcomings of the other approaches. (shrink)

In this paper I will be arguing that there are cases in which a subject, S, should have known that p, even though, given her state of evidence at the time, she was in no position to know it. My argument for this result will involve making two claims. The uncontroversial claim is this: S should have known that p when another person has, or would have, legitimate expectations regarding S’s epistemic condition, the satisfaction of these expectations would require that (...) S knows that p, and S fails to know that p. The controversial claim is that these three conditions are sometimes jointly satisfied. I will spend the majority of my time defending the controversial claim. I will argue that there are two main sources of legitimate expectations regarding another’s epistemic condition: participation in a legitimate social practice ; and moral and epistemic expectations more generally . In developing my position on this score, I will have an opportunity to defend the doctrine that there are “practice-generated entitlements” to expect certain things, where it can happen that the satisfaction of these expectations requires another’s having certain pieces of knowledge; to contrast practice-generated entitlements to expect with epistemic reasons to believe; to defend the idea that moral and epistemic standards themselves can be taken to reflect legitimate expectations we have of each other; to compare the “should have known” phenomenon with a widely-discussed phenomenon in the ethics literature—that of culpable ignorance; and finally to suggest the bearing of the “should have known” phenomenon to epistemology itself. (shrink)

Russian translation of Gettier E. L. Is Justified True Belief Knowledge? // Analysis, vol. 23, 1963. Translated by Lev Lamberov with kind permission of the author.

Epistemic akrasia arises when one holds a belief even though one judges it to be irrational or unjustified. While there is some debate about whether epistemic akrasia is possible, this paper will assume for the sake of argument that it is in order to consider whether it can be rational. The paper will show that it can. More precisely, cases can arise in which both the belief one judges to be irrational and one’s judgment of it are epistemically rational in (...) the sense that both are supported by sufficient evidence. (shrink)

I extend the Higher-Order View of Undermining Defeat (HOVUD) defended in Melis (2014) to account for the defeat of propositional justification. In doing so, I clarify the important notion of higher-order commitment, and I make some considerations concerning the defeat of externalist epistemic warrants.