You reach for the bowl with ‘sugar’ written on it only to discover, from the bad taste of your coffee, that it contained salt. Mundane experiences like these show that epistemic justification does not necessarily hold stable across possible changes of information. One can be justified in believing a proposition at a certain time (that the bowl contains sugar) and cease to be justified at a later time, as one enlarges one’s epistemic perspective (as one drinks a salty (...) coffee). When this happens, one’s justification has been defeated. An epistemic defeater, broadly speaking, is that in terms of which the defeat of justification proceeds. The notion of an epistemic defeater is mostly associated with J. Pollock’s work on reasoning and inference. Pollock has provided the canonical definition of an epistemic defeater and proposed an influential taxonomy in terms of the way different types of defeaters induce their characteristic effects. The notion of an epistemic defeater has acquired a broader meaning in current epistemology, and several distinctions have been introduced that have contributed to a more nuanced understanding of the phenomenon of defeat as well as to complement Pollock’s original taxonomy. The correlated notion of a propositional defeater, defined in terms of would-be defeat of justification, is appealed to by the proponents of the defeasibility theory in the parallel debate about knowledge to explain what prevents a justified true belief from constituting knowledge in Gettier cases. (shrink)

We aim to further develop and evaluate the prospects of a uniquely Islamic extension of the Standard Aquinas/Calvin model. One obstacle is that certain Qur’an passages such as Surah 8:43–44 apparently suggest that Muslims have reason to think that Allah might be deceiving them. Consistent with perfect/maximally good being theology, Allah would allow such deceptions only if doing so leads to a greater good, so such passages do not necessarily give Muslims reason to doubt Allah’s goodness. Yet the possibility of (...) deception of the faithful threatens to provide a subjective defeater for the (epistemic) reliability of their cognitive faculties. (‘Even if Allah can be morally good while deceiving, how do you know you aren’t being deceived for a greater good on a more macro level, such as about the nature of the Qur’an?’) Similar in structure to Alvin Plantinga’s Evolutionary Argument Against Naturalism (EAAN), this defeater threatens to undermine all of a Muslims warrant claims. We consider and evaluate the reply that there are other Qur’anic passages and/or additional conceptual resources in the Islamic tradition that provide grounds for thinking that God’s faithfulness or truthfulness is more centrally and securely embedded in a Muslim’s noetic structure than such doubts. Specifically, we will argue that under certain conditions, there exists a subjective defeater for some Muslims that, unlike McNabb’s approach, isn’t based off of the proper function condition but Plantinga’s truth aimed condition. (shrink)

. This article seeks to outline how a Muslim believer can deflect a defeater for Islamic belief put forward by Erik Baldwin and Tyler McNabb. In doing so, it aims to reject the suggestion that an Islamic religious epistemology is somehow antithetical to a model of Reformed epistemology which is not fully compatible with Plantingian. Taken together with previous work on Islam and RE, the article not only aims to provide reason to think that Baldwin and McNabb’s proposed epistemic (...) defeater for Islamic belief isn’t problematic, it also seeks to show how the concerns raised by Baldwin and McNabb over a Plantingian model of RE in Islamic milieu, are no longer tenable. (shrink)

A number of well-developed theories shed light on the question, under what circumstances our beliefs enjoy epistemic justification. Yet, comparatively little is known about epistemic defeat--when new information causes the loss of epistemic justification. This book proposes and defends a detailed account of epistemic defeaters. The main kinds of defeaters are analyzed in detail and integrated into a general framework that aims to explain how beliefs lose justification. It is argued that defeaters introduce (...) incompatibilities into a noetic system and thereby prompt a structured re-evaluation process that makes a justified reinstatement of the defeated belief impossible. The account is then applied to the topic of disagreement, where it is used in an argument for conciliationism, as well as a new explanation for higher-order defeat. Throughout the book, the notion of defeat is the center of attention, while a number of new issues are discussed at the intersections of defeat and justification. Specifically, new problems are raised for broadly internalist accounts of defeat, a fully descriptive reliabilist account of defeat is provided, and the case for normative defeat is revisited. (shrink)

An account of meta-epistemic defeaters—distinct from traditional epistemic defeaters—is motivated and defended, drawing from case studies involving epistemic error-theory and epistemic relativism. Mechanisms of traditional epistemic defeat and meta-epistemic defeat are compared and contrasted, and some new puzzles are introduced.

In this article, I develop two arguments against the Asharite metaethical theory concerning God’s actions. First, I purport that the probability of God’s revelation being true given that the Asharite metaethical theory obtains is low. However, as some Asharites might point out, the probability increases by considering other items from the Asharite theology, which ultimately renders the first argument flawed. I further argue that the probability of our cognitive faculties being reliable given the Asharite metaethical theory concerning God’s action being (...) true is rather low. I establish that this renders the Asharite metaethical theory self-referentially incoherent. I then provide another version of the second argument that avoids the reference to conditional probability in an attempt to undercut any objection that depends on the usage of conditional probability in the second argument. (shrink)

If individual knowledge and justification can be vanquished by epistemic defeaters, then the same should go for group knowledge. Lackey (2014) has recently argued that one especially strong conception of group knowledge defended by Bird (2010) is incapable of preserving how it is that (group) knowledge is ever subject to ordinary mechanisms of epistemic defeat. Lackey takes it that her objections do not also apply to a more moderate articulation of group knowledge--one that is embraced widely in (...) collective epistemology--and which she does not challenge. This paper argues that given certain background premises that are embraced by orthodox thinking in collectivist epistemology, the more moderate account of group knowledge cannot make sense of either psychological or normative epistemic defeaters. I conclude by offering some suggestions for how the more moderate proposal might avoid this result. (shrink)

In this paper, I outline some exegetical and philosophical problems with Baldwin and McNabb’s epistemic defeater for Islamic beliefs. I maintain that their argument is based upon a misinterpretation of Quranic verses. I also argue that exceptional instances of divine deception inflicted upon the senses, if they indeed happen, should not undermine the general trust in our cognitive faculties. I conclude that virtually all Muslims are immune from Baldwin and McNabb’s proposed defeater and from the threat posed by divine (...) deception in general. (shrink)

In this paper, I outline some exegetical and philosophical problems with Baldwin and McNabb’s epistemic defeater for Islamic beliefs. I maintain that their argument is based upon a misinterpretation of Quranic verses. I also argue that exceptional instances of divine deception inflicted upon the senses, if they indeed happen, should not undermine the general trust in our cognitive faculties. I conclude that virtually all Muslims are immune from Baldwin and McNabb’s proposed defeater and from the threat posed by divine (...) deception in general. (shrink)

There are two different kinds of theories of the concept of epistemic defeat. One theory begins with propositional relationships, only by implication describing what happens in the context of a noetic system. Such a theory places inforrmation about defeat up front, not informing us of how the defeat relationships play out in the context of actual belief, at least not initially. The other theory takes a back door to the concept of defeat, assuming a context of actual belief and (...) an entire noetic system, and describing defeat in terms of what sort of doxastic and noetic responses would be appropriate to the addition of particular pieces of information. Where the house is the noetic structure itself, the front door approach characterizes the concept of defeat in terms of the propositional contents a belief might have, thus characterizing defeat at the front door. The backdoor approach characterizes defeat in terms of what leaves the house, in terms of beliefs that exit the noetic system in response to changes to it, in terms of what the staff of a well-run household kicks out the backdoor for making a mess of things. Alvin Plantinga’s theory of epistemic defeat is a back-door theory, and here I will argue that his theory and approaches like it will be unable to explicate accurately the concept of epistemic defeat. I will argue that a front door approach is needed rather than a back door approach. (shrink)

This paper explores how a certain theory of knowledge—known as anti-luck virtue epistemology—can account for, and in the process shed light on, the notion of an epistemic defeater. To this end, an overview of the motivations for anti-luck virtue epistemology is offered, along with a taxonomy of different kinds of epistemic defeater. It is then shown how anti-luck virtue epistemology can explain: why certain kinds of putative epistemic defeater are not bona fide; how certain kinds of (...) class='Hi'>epistemic defeater are genuine in virtue of exposing the subject to significant levels of epistemic risk; and how certain kinds of epistemic defeater are genuine in virtue of highlighting how the subject’s safe cognitive success does not stand in the appropriate explanatory relationship to her manifestation of relevant cognitive ability. (shrink)

In this paper, I present a solution to the problem that the need to accommodate the phenomenon of epistemic defeat poses for reliabilism. Defeaters are supposed to remove justification for previously justified beliefs. According to standard process reliabilism, the justification of a belief depends on the reliability of a process that is already completed when a defeater for that belief is obtained. It is hard to see, then, how a defeater can affect reliabilist justification, if that justification, from (...) the perspective of the defeater, lies wholly in the past. What is more, undercutting defeaters plausibly defeat by generating incompatibilities with higher-order propositions :105–118, 2014; Melis in Philos Stud 170:433–442, 2014). This is hard to integrate with reliabilism which explicitly denies higher-order conditions for justification. I argue that both of these phenomena can be accommodated by it via what I call the “Replacement Principle”: when a defeater is obtained, it generates either a logical incompatibility or a doxastic incompatibility. The resulting tension is registered and initiates a reasoning process that compares the epistemic support for the defeater with that for the defeated belief. This process may replace the original reliable formation process as a doxastic base for the defeated belief. If the defeater is not given its due weight in the reasoning process, that process was unreliable and if the defeated belief is retained as a result, it will be unjustified. This is intuitively the right result. Since reasoning is reliable, only if it is rational, the account manages to capture the intuition that disregarding a defeater would be irrational without having to make rationality a condition for justification. Replacement is not only plausible on causal pictures of doxastic basing, but also required in order to allow for the possibility of belief reevaluation in general and is therefore not an ad hoc addition to reliabilism, but rather part of its inherent explanatory resources. (shrink)

Shared decision-making involves health professionals and patients/clients working together to achieve true person-centred health care. However, this goal is infrequently realized, and most barriers are unknown. Discussion between philosophers, clinicians, and researchers can assist in confronting the epistemic and moral basis of health care, with benefits to all. The aim of this paper is to describe what shared decision-making is, discuss its necessary conditions, and develop a definition that can be used in practice to support excellence in maternity care. (...) Discussion between the authors, with backgrounds in philosophy, clinical maternity care, health care management, and maternity care research, assisted the team to confront established norms in maternity care and challenge the epistemic and moral basis of decision-making for caesarean section. The team concluded that shared decision-making must start in pregnancy and continue throughout labour and birth, with equality in discourse facilitated by the clinician. Clinicians have a duty of care for the adequacy of women's knowledge, which can only be fulfilled when relevant knowledge is offered freely and when personal beliefs and biases that may impinge on decision-making (defeaters) are disclosed. Informed consent is not shared decision-making. Key barriers include existing cultural norms of “the doctor knows best” and “patient acquiescence” that prevent defeaters being acknowledged and discussed and can lead to legal challenges, overuse of medical intervention and, in some areas, obstetric violence. Shared decision-making in maternity care can thus be defined as an enquiry by clinician and expectant woman aimed at deciding upon a course of care or none, which takes the form of a dialogue within which the clinician fulfils their duty of care to the client's knowledge by making available their complete knowledge (based on all types of evidence) and expertise, including an exposition of any relevant and recognized potential defeaters. Research to develop measurement tools is required. (shrink)

Despite its central role in our cognitive lives, rational belief revision has received relatively little attention from epistemologists. This dissertation begins to fill that absence. In particular, we explore the phenomenon of defeasible epistemic justification, i.e., justification that can be lost as well as gained by epistemic agents. We begin by considering extant theories of defeat, according to which defeaters are whatever cause a loss of justification or things that somehow neutralize one's reasons for belief. Both of (...) these theories are both extensionally and explanatorily inadequate and, so, are rejected. We proceed to develop a novel theory of defeat according to which defeaters are reasons against belief. According to this theory, the dynamics of justification are explained by the competition between reasons for and reasons against belief. We find that this theory not only handles the counter-examples that felled the previous theories but also does a fair job in explaining the various aspects of the phenomenon of defeat. Furthermore, this theory accomplishes this without positing any novel entities or mechanisms; according to this theory, defeaters are epistemic reasons against belief, the mirror image of our epistemic reasons for belief, rather than sui generis entities. (shrink)

Reflection on the history of skepticism shows that philosophers have often conjoined as a single doctrine various theses that are best kept apart. Some of these theses are incredible – literally almost impossible to accept – whereas others seem quite plausible, and even verging on the platitudinous. Mixing them together, one arrives at a view – skepticism – that is as a whole indefensible. My aim is to pull these different elements apart, and to focus on one particular strand of (...) skepticism that deserves sustained and respectful attention. The strand I have in mind I will refer to as epistemic defeatism. Roughly, in its most global form, it is the view that, in the final analysis, we have no good evidence for the truth of any proposition. Working through various historical texts, I attempt to untangle epistemic defeatism from neighboring views, and in particular to establish its independence from questions about knowledge. Having thus established the view's autonomy, I turn to the options for self-consciously accepting defeat. One may despair or one may have faith. But I will ultimately propose that the most attractive option – the option that preserves the most of our epistemic integrity – is to have hope. (shrink)

An argument is epistemically self-defeating when either the truth of an argument’s conclusion or belief in an argument’s conclusion defeats one’s justification to believe at least one of that argument’s premises. Some extant defenses of the evidentiary value of intuition have invoked considerations of epistemic self-defeat in their defense. I argue that there is one kind of argument against intuition, an unreliability argument, which, even if epistemically self-defeating, can still imply that we are not justified in thinking intuition has (...) evidentiary value. (shrink)

Several anti-debunkers have argued that evolutionary explanations of our moral beliefs fail to meet a necessary condition on undermining defeat called modal security. They conclude that evolution, therefore, does not debunk our moral beliefs. This article shows that modal security is false if knowledge is virtuous achievement. New information can undermine a given belief without providing reason to doubt that that belief is sensitive or safe. This leads to a novel conception of undermining defeat, and it shows that successful debunking (...) of moral realism is possible. (shrink)

Modern societies are characterized by a division of epistemic labor between laypeople and epistemic authorities. Authorities are often far more competent than laypeople and can thus, ideally, inform their beliefs. But how should laypeople rationally respond to an authority’s beliefs if they already have beliefs and reasons of their own concerning some subject matter? According to the standard view, the beliefs of epistemic authorities are just further, albeit weighty, pieces of evidence. In contrast, the Preemption View claims (...) that, when one discovers what an authority believes, it is not permissible to rely on any of one’s own reasons concerning the subject matter. The original version of this view, as proposed by Linda Zagzebski, has recently been severely criticized for recommending blind trust and for abandoning even minimal standards for critical thinking. In our paper, we defend a new version of the Preemption View—Defeatist Preemptionism—in a way that differs radically from Zagzebski’s. We argue that our view can be derived from certain widely accepted general epistemic principles. In particular, we claim that preemption can be identified as a special case of source sensitive defeat. Moreover, we argue that Defeatist Preemptionism does not lead to the undesirable consequences that critics ascribe to the Preemption View. The paper thus articulates the foundations and refinements of the Preemption View, such that it adequately captures the phenomenon of epistemic authority and the rational requirements related to it. (shrink)

The post-Gettier literature contained many views that tried to solve the Gettier problem by appealing to the notion of defeat. Unfortunately, all of these views are false. The failure of these views greatly contributed to a general distrust of reasons in epistemology. However, reasons are making a comeback in epistemology, both in general and in the context of the Gettier problem. There are two main aims of this paper. First, I will argue against a natural defeat based resolution of the (...) Gettier problem. Second, I will defend my own defeat based solution. This solution appeals to a modal anti-luck condition. I will argue that this condition captures anti-luck intuitions and has virtues that rival modal anti-luck conditions lack. (shrink)

I critically examine two features of Plantinga’s Reformed Epistemology. (i) If basic theistic beliefs are threatened by defeaters (of various kinds) and thus must be defended by higher-order defeaters in order to remain rational and warranted, are they still “properly basic”? (ii) Does Plantinga’s overall account offer an argument that basic theistic beliefs actually are warranted? I answer both questions in the negative.

Many epistemologists are enamored with a defeat condition on knowledge. In this paper we present some implementation problems for defeatism, understood along either internalist or externalist lines. We then propose that one who accepts a knowledge norm of belief, according to which one ought to believe only what one knows, can explain away much of the motivation for defeatism. This is an important result, because on the one hand it respects the plausibility of the intuitions about defeat shared by many (...) in epistemology; but on the other hand, it obviates the need to provide a unified account of defeat which plays well with the most plausible views of how knowledge fits with evidential probability. (shrink)

This chapter investigates the rationality of failing to believe miracle reports. Hume famously argued that it is irrational to believe that a miracle has occurred on the basis of testimony alone. While certain aspects of Hume's argument have received extensive discussion, other features of his argument have been largely overlooked. After offering a reconstruction of Hume's argument, I argue that epistemic defeat plays a central role in the argument, and I explore the aptness of as well as some limitations (...) to Hume's reasoning. I then discuss the relevance of the prior likelihood of an event when evaluating the evidential strength that testimony to such an event provides. Finally, I explore some ways the argument is altered if we adopt a non-traditional picture of evidence and defeat. (shrink)

Many epistemologists have endorsed a version of the view that rational belief is sensitive to higher-order defeat. That is to say, even a fully rational belief state can be defeated by misleading higher-order evidence, which indicates that the belief state is irrational. In a recent paper, however, Maria Lasonen-Aarnio calls this view into doubt. Her argument proceeds in two stages. First, she argues that higher-order defeat calls for a two-tiered theory of epistemic rationality. Secondly, she argues that there seems (...) to be no satisfactory way of avoiding epistemic dilemmas within a two-tiered framework. Hence, she concludes that the prospects look dim for making sense of higher-order defeat within a broader theoretical picture of epistemic rationality. Here I aim to resist both parts of Lasonen-Aarnio’s challenge. First, I outline a way of accommodating higher-order defeat within a single-tiered framework, by amending epistemic rules with appropriate provisos for different kinds of higher-order defeat. Secondly, I argue that those who nevertheless prefer to accommodate higher-order defeat within a two-tiered framework can do so without admitting to the possibility of epistemic dilemmas, since epistemic rules are not always accompanied by ‘oughts’ in a two-tiered framework. The considerations put forth thus indirectly vindicate the view that rational belief is sensitive to higher-order defeat. (shrink)

Justification depends on context: even if E on its own justifies H, still it might fail to justify in the context of D. This sort of effect, epistemologists think, is due to defeaters, which undermine or rebut a would-be justifier. I argue that there is another fundamental sort of contextual feature, disqualification, which doesn't involve rebuttal or undercutting, and which cannot be reduced to any notion of screening-off. A disqualifier makes some would-be justifier otiose, as direct testimony sometimes does (...) to distal testimony, and as manifestly decisive evidence might do to gratuitous evidence on the same team. Basing a belief on disqualified evidence, moreover, is distinctively irrational. One is not necessarily irresponsible. Instead one is turning down a free upgrade to a sleeker, stabler basis for one's beliefs. Such an upgrade would prevent wastes of epistemic effort, since someone who bases her belief on a disqualified proposition E will need to remember E and rethink her belief should E ever be defeated. The upgrade might also reduce reliance on unwieldy evidence, if E is relevant only thanks to some labyrinthine argument; and if even ideal agents should doubt their ability to follow such arguments, even they should care about disqualifiers. (shrink)

When and why does awareness of a belief's genealogy render it irrational to continue holding that belief? According to explanationism, awareness of a belief’s genealogy gives rise to an epistemic defeater when and because it reveals that the belief is not explanatorily connected to the relevant worldly facts. I argue that an influential recent version of explanationism, due to Korman and Locke, incorrectly implies that it is not rationally permissible to adopt a “sparse” ontology of worldly facts or states (...) of affairs. I then propose a new explanationist account of genealogical defeat capable of accommodating rational belief in ontological sparsity. According to my account, awareness of a belief’s genealogy gives rise to a defeater when and because it reveals that the belief is not explanatorily connected to its truthmaker. (shrink)

One emerging issue in contemporary epistemology concerns the relation between animal knowledge, which can be had by agents unable to take a view on the epistemic status of their attitudes, and reflective knowledge, which is only available to agents capable of taking such a view. Philosophers who are open to animal knowledge often presume that while many of the beliefs of human adults are formed unreflectively and thus constitute mere animal knowledge, some of them—those which become subject of explicit (...) scrutiny or are the result of a deliberative effort—may attain the status of reflective knowledge. According to Sanford Goldberg and Jonathan Matheson (2020), however, it is impossible for reflective subjects to have mere animal knowledge. If correct, their view would have a number of repercussions, perhaps most notably the vindication of a dualism about knowledge, which would frustrate attempts to provide a unified account of knowledge-attributions to human adults, very young children, and non-human animals. I discuss Goldberg and Matheson’s proposal, outline some of the ways in which it is insightful, and argue that it is ultimately unsuccessful because it neglects the inherent temporal dimension of knowledge acquisition. While the article is pitched as a reply to Goldberg and Matheson, its primary aim is to highlight significant connections between the debates on the relation between animal and reflective knowledge, propositional and doxastic justification, and the theory of epistemic defeat. (shrink)

Epistemic defeat is standardly understood in either evidentialist or responsibilist terms. The seminal treatment of defeat is an evidentialist one, due to John Pollock, who famously distinguishes between undercutting and rebutting defeaters. More recently, an orthogonal distinction due to Jennifer Lackey has become widely endorsed, between so-called doxastic (or psychological) and normative defeaters. We think that neither doxastic nor normative defeaters, as Lackey understands them, exist. Both of Lackey’s categories of defeat derive from implausible assumptions about (...) epistemic responsibility. Although Pollock’s evidentialist view is superior, the evidentialism per se can be purged from it, leaving a general structure of defeat that can be incorporated in a reliabilist theory that is neither evidentialist nor responsibilist in any way. (shrink)

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)

This chapter provides a critical overview of several influential proposals about the epistemic function of higher-order evidence. I start by criticizing accounts of higher-order evidence that appeal to evidential defeat (§1), epistemic conflicts (§2), and unreasonable knowledge (§3). Next, I propose an alternative account that appeals to a combination of improper basing (§4) and non-ideal rationality (§5). Finally, I conclude by summarizing my reasons for preferring this account of higher-order evidence to the alternatives (§6).

Evidentialism is the thesis, roughly, that one’s beliefs should fit one’s evidence. The enkratic principle is the thesis, roughly, that one’s beliefs should "line up" with one’s beliefs about which beliefs one ought to have. While both theses have seemed attractive to many, they jointly entail the controversial thesis that self-misleading evidence is impossible. That is to say, if evidentialism and the enkratic principle are both true, one’s evidence cannot support certain false beliefs about which beliefs one’s evidence supports. Recently, (...) a number of epistemologists have challenged the thesis that self-misleading evidence is impossible on the grounds that misleading higher-order evidence does not have the kind of strong and systematic defeating force that would be needed to rule out the possibility of such self-misleading evidence. Here I respond to this challenge by proposing an account of higher-order defeat that does, indeed, render self-misleading evidence impossible. Central to the proposal is the idea that higher-order evidence acquires its normative force by influencing which conditional beliefs it is rational to have. What emerges, I argue, is an independently plausible view of higher-order evidence, which has the additional benefit of allowing us to reconcile evidentialism with the enkratic principle. (shrink)

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)

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)

This paper proposes a new externalist account of defeaters, in terms of reliable indicators, as an integral part of a unified externalist account of warrant and defeat. It is argued that posing externalist conditions on warrant, but internalist conditions on defeat lead to undesirable tensions. The proposal is contrasted to some rival accounts and then tested on some widely discussed cases, like the airport case. Misleading defeaters, where Laurence BonJour’s reliable clairvoyants serve as examples, also receive treatment, partly (...) because they illustrate how internalist constraints are inserted into the set up of the problem and therefore unduly constrain the domain of satisfactory solutions. Lastly, the proposal is defended against some objections. Firstly, that by posing externalist conditions on defeat, the account becomes too open. Secondly, that an externalist account fails to take into account the epistemic assessments of our fellows in the epistemic practice of forming beliefs and making epistemic claims, which can be based on accessible warrant only. (shrink)

According to the phenomenal conservatives, beliefs are justified by non-doxastic states we might speak of as ‘appearances’ or ‘seemings’. Those who defend the view say that there is something self-defeating about believing that phenomenal conservatism is mistaken. They also claim that the view captures an important internalist insight about justification. I shall argue that phenomenal conservatism is indefensible. The considerations that seem to support the view commit the phenomenal conservatives to condoning morally abhorrent behavior. They can deny that their view (...) forces them to condone morally abhorrent behavior, but then they undercut the defenses of their own view. (shrink)

When P(E) > 0, conditional probabilities P(H|E)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(H|E)$$\end{document} are given by the ratio formula. An agent engages in ratio conditionalization when she updates her credences using conditional probabilities dictated by the ratio formula. Ratio conditionalization cannot eradicate certainties, including certainties gained through prior exercises of ratio conditionalization. An agent who updates her credences only through ratio conditionalization risks permanent certainty in propositions against which she has overwhelming evidence. To avoid this undesirable consequence, (...) I argue that we should supplement ratio conditionalization with Kolmogorov conditionalization, a strategy for updating credences based on propositions E such that P(E) = 0. Kolmogorov conditionalization can eradicate certainties, including certainties gained through prior exercises of conditionalization. Adducing general theorems and detailed examples, I show that Kolmogorov conditionalization helps us model epistemic defeat across a wide range of circumstances. (shrink)

I make a case for distinguishing clearly between subjective and objective accounts of undercutting defeat and for rejecting a hybrid view that takes both subjective and objective elements to be relevant for whether or not a belief is defeated. Moderate subjectivists claim that taking a belief to be defeated is sufficient for the belief to be defeated; subjectivist idealists add that if an idealised agent takes a belief to be defeated then the belief is defeated. Subjectivist idealism evades some of (...) the objections levelled against moderate subjectivism but can be shown to yield inconsistent results in some cases. Both subjectivisms should be rejected. We should be objectivists regarding undercutting defeat. This requirement, however, is likely to be problematic for a popular interpretation of evolutionary debunking arguments in metaethics as it can be shown that existing objectivist accounts of defeat do not support such arguments. I end by discussing the constraints of developing such an account. (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.

In recent years there has been an explosion of interest in Artificial Intelligence (AI) both in health care and academic philosophy. This has been due mainly to the rise of effective machine learning and deep learning algorithms, together with increases in data collection and processing power, which have made rapid progress in many areas. However, use of this technology has brought with it philosophical issues and practical problems, in particular, epistemic and ethical. In this paper the authors, with backgrounds (...) in philosophy, maternity care practice and clinical research, draw upon and extend a recent framework for shared decision-making (SDM) that identified a duty of care to the client's knowledge as a necessary condition for SDM. This duty entails the responsibility to acknowledge and overcome epistemic defeaters. This framework is applied to the use of AI in maternity care, in particular, the use of machine learning and deep learning technology to attempt to enhance electronic fetal monitoring (EFM). In doing so, various sub-kinds of epistemic defeater, namely, transparent, opaque, underdetermined, and inherited defeaters are taxonomized and discussed. The authors argue that, although effective current or future AI-enhanced EFM may impose an epistemic obligation on the part of clinicians to rely on such systems' predictions or diagnoses as input to SDM, such obligations may be overridden by inherited defeaters, caused by a form of algorithmic bias. The existence of inherited defeaters implies that the duty of care to the client's knowledge extends to any situation in which a clinician (or anyone else) is involved in producing training data for a system that will be used in SDM. Any future AI must be capable of assessing women individually, taking into account a wide range of factors including women's preferences, to provide a holistic range of evidence for clinical decision-making. (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)

Can known disagreement with our epistemic peers undermine or defeat the justification our beliefs enjoy? Much of the current literature argues for one of two extreme positions on this topic, either that the justification of each person's belief is (fully) defeated by the awareness of disagreement, or that no belief is defeated by this awareness. I steer a middle course and defend a principle describing when a disagreement yields a partial defeater, which results in a loss of some, but (...) not all, of the justification of a belief. I show that the 'no defeater' view is too strong. I also offer reasons for thinking that the 'full defeater' view is similarly mistaken. (shrink)

Subjects who retain their beliefs in the face of higher-order evidence that those very beliefs are outputs of flawed cognitive processes are at least very often criticisable. Many think that this is because such higher-order evidence defeats various epistemic statuses such as justification and knowledge, but it is notoriously difficult to give an account of such defeat. This paper outlines an alternative explanation, stemming from some of my earlier work, for why subjects are criticisable for retaining beliefs in the (...) face of paradigm kinds of putatively defeating higher-order evidence: they manifest dispositions that are bad relative to a range of candidate epistemic successes such as true belief and knowledge. In particular, giving up belief in response to higher-order evidence only when that evidence is not misleading would require subjects to have dispositions that discriminate between cases in which their original cognitive processes is fine, and cases in which they merely seemed to be fine. But, I argue, such dispositions are not normally humanly feasible. I show that retaining belief in putative cases of defeat by higher-order evidence is problematic irrespective of whether veritism or some form of gnosticism is true. In the end I contrast my account of dispositional evaluations with similar-sounding ideas that have been put forth in the literature, such as consequentialist views that focus on instrumental means to success. (shrink)

It is currently fashionable to hold that deontology induces internalism. That is, those who think that epistemic justification is essentially a matter of duty fulfillment are thought to have a good reason for accepting internalism in epistemology. I shall argue that no deontological conception of epistemic justification provides a good reason for endorsing internalism. My main contention is that a requirement having to do with epistemic defeat---a requirement that many externalists impose on knowledge---guarantees the only sorts of (...) deontological justification that have a chance at inducing internalism. Given this compatibility of externalism and deontology, we may safely conclude that deontology by itself doesn’t lend support to internalism. (shrink)

It is currently fashionable to hold that deontology induces internalism. That is, those who think that epistemic justification is essentially a matter of duty fulfillment are thought to have a good reason for accepting internalism in epistemology. I shall argue that no deontological conception of epistemic justification provides a good reason for endorsing internalism. My main contention is that a requirement having to do with epistemic defeat---a requirement that many externalists impose on knowledge---guarantees the only sorts of (...) deontological justification that have a chance at inducing internalism. Given this compatibility of externalism and deontology, we may safely conclude that deontology by itself doesn’t lend support to internalism. (shrink)

I address Andrew Moon's recent discussion (2016, this journal) of the question whether third-factor accounts are valid responses to debunking arguments against moral realism. Moon argues that third-factor responses are valid under certain conditions but leaves open whether moral realists can use his interpretation of the third-factor response to defuse the evolutionary debunking challenge. I rebut Moon's claim and answer his question. Moon's third-factor reply is valid only if we accept externalism about epistemic defeaters. However, even if we (...) do, I argue, the conditions Moon identifies for a valid third-factor response are not met in the case of moral realism. (shrink)

Conciliatory views about disagreement with one’s epistemic peers lead to a somewhat troubling skeptical conclusion: that often, when we know others disagree, we ought to be (perhaps much) less sure of our beliefs than we typically are. One might attempt to extend this skeptical conclusion by arguing that disagreement with merely possible epistemic agents should be epistemically significant to the same degree as disagreement with actual agents, and that, since for any belief we have, it is possible that (...) someone should disagree in the appropriate way, we ought to be much less sure of all of our beliefs than we typically are. In this paper, I identify what I take to be the main motivation for thinking that actual disagreement is epistemically significant and argue that it does not also motivate the epistemic significance of merely possible disagreement. (shrink)