How should you update your (degrees of) belief about a proposition when you find out that someone else — as reliable as you are in these matters — disagrees with you about its truth value? There are now several different answers to this question — the question of `peer disagreement' — in the literature, but none, I think, is plausible. Even more importantly, none of the answers in the literature places the peer-disagreement debate in its natural place among the most (...) general traditional concerns of normative epistemology. In this paper I try to do better. I start by emphasizing how we cannot and should not treat ourselves as `truthometers' — merely devices with a certain probability of tracking the truth. I argue that the truthometer view is the main motivation for the Equal Weight View in the context of peer disagreement. With this fact in mind, the discussion of peer disagreement becomes more complicated, sensitive to the justification of the relevant background degrees of belief (including the conditional ones), and to some of the most general points that arise in the context of discussions of scepticism. I argue that thus understood, peer disagreement is less special as an epistemic phenomenon than may be thought, and so that there is very little by way of positive theory that we can give about peer disagreement in general. (shrink)

Two compelling principles, the Reasonable Range Principle and the Preservation of Irrelevant Evidence Principle, are necessary conditions that any response to peer disagreements ought to abide by. The Reasonable Range Principle maintains that a resolution to a peer disagreement should not fall outside the range of views expressed by the peers in their dispute, whereas the Preservation of Irrelevant Evidence Principle maintains that a resolution strategy should be able to preserve unanimous judgments of evidential irrelevance among the peers. No standard (...) Bayesian resolution strategy satisfies the PIE Principle, however, and we give a loss aversion argument in support of PIE and against Bayes. The theory of imprecise probability allows one to satisfy both principles, and we introduce the notion of a set-based credal judgment to frame and address a range of subtle issues that arise in peer disagreements. (shrink)

How should you take into account the opinions of an advisor? When you completely defer to the advisor's judgment, then you should treat the advisor as a guru. Roughly, that means you should believe what you expect she would believe, if supplied with your extra evidence. When the advisor is your own future self, the resulting principle amounts to a version of the Reflection Principle---a version amended to handle cases of information loss. When you count an advisor as an epistemic (...) peer, you should give her conclusions the same weight as your own. Denying that view---call it the ``equal weight view''---leads to absurdity: the absurdity that you could reasonably come to believe yourself to be an epistemic superior to an advisor simply by noting cases of disagreement with her, and taking it that she made most of the mistakes. Accepting the view seems to lead to another absurdity: that one should suspend judgment about everything that one's smart and well-informed friends disagree on, which means suspending judgment about almost everything interesting. But despite appearances, the equal weight view does not have this absurd consequence. Furthermore, the view can be generalized to handle cases involving not just epistemic peers, but also epistemic superiors and inferiors. (shrink)

Recent philosophical discussions construe disagreement as epistemically unsettling. On learning that a peer disagrees, it is said, you should suspend judgment, lower your credence, or dismiss your peer’s conviction as somehow flawed, even if you can neither identify the flaw nor explain why you think she is the party in error. Philosophers do none of these things. A distinctive feature of philosophy as currently practiced is that, although we marshal the strongest arguments we can devise, we do not expect others (...) to agree. Nor are we dismayed then they do not. Through a survey of familiar professional practices, I argue that philosophy rightly revels in responsible disagreement. This discloses important and perhaps surprising facets of the epistemology of philosophy. (shrink)

Advocates of epistemic conceptions of democracy sometimes argue that democratic decision-making is a more reliable guide to getting the issues at stake right than the decision-making of individuals. Such arguments give rise to the question of whether those finding themselves in the minority should defer to democratic outcomes. In this article, I discuss the bearing of the normative criterion of reasonable acceptability on this question. I thus ask, can the demand to defer to democratic outcomes be rendered reasonably acceptable to (...) citizens who disagree with them? Using the example of David Estlund’s epistemic proceduralism, I show that the problem of moral deference is inherent to epistemic conceptions of democracy. I then discuss the kind of reasons that would make a demand of deference reasonably acceptable to the minority, arguing that they should be independent from the reasons supporting the majority position. Subsequently, I introduce the conciliatory conception of democracy as an example of what such reasons could be. The conception’s central idea is that disagreement between citizens conceived as equal epistemic authorities carries epistemic significance. This significance makes it rational for citizens so conceived to conciliate their conflicting judgments. Because democratic decision-making has an inbuilt tendency to track such conciliatory positions, the conception offers an independent reason to accept democratic outcomes as the more reliable guide to getting the issues at stake right. (shrink)

Abstract: Recent years have witnessed a revival of interest in relativism. Proponents have defended various accounts that seek to model the truth-conditions of certain propositions along the lines of standard possible world semantics. The central challenge for such views has been to explain what advantage they have over contextualist theories with regard to the possibility of disagreement. I will press this worry against Max Kölbel’s account of faultless disagreement. My case will proceed along two distinct but connected lines. First, I (...) will argue that the sense of faultlessness made possible by his relativism conflicts with our intuitive understanding of disagreement. And second, that his meta-epistemological commitments are at odds with the socio-epistemic function of disagreement. This latter problem for relativistic accounts of truth has thus far been largely ignored in the literature. (shrink)

The purpose of this paper is to challenge what is often called the “Uniqueness” thesis. According to this thesis, given one’s total evidence, there is a unique rational doxastic attitude that one can take to any proposition. It is sensible for defenders of Uniqueness to commit to an accompanying principle that: when some agent A has equal epistemic reason both to believe that p and to believe that not p, the unique epistemically rational doxastic attitude for A to adopt with (...) respect to whether p is the suspension of judgment. In this paper, I offer a case wherein the agent has equal epistemic reason both to believe that p and to believe that not p, but the agent is not epistemically required to suspend judgment about whether p. Furthermore, the case is such that there seems to be no uniquely rational attitude for the agent to adopt. (shrink)

It has been claimed that epistemic peers, upon discovering that they disagree on some issue, should give up their opposing views and ‘split the difference’. The present paper challenges this claim by showing, with the help of computer simulations, that what the rational response to the discovery of peer disagreement is—whether it is sticking to one’s belief or splitting the difference—depends on factors that are contingent and highly context-sensitive.Keywords: Peer disagreement; Computer simulations; Opinion dynamics; Hegselmann–Krause model; Social epistemology.

Abstract: This paper argues that instances of what are typically called ‘epistemic irresponsibility’ are better understood as instances of moral or prudenial failure. This hypothesis covers the data and is simpler than postulating a new sui generis form of normativitiy. The irresponsibility alleged is that embeded in charges of ‘You should have known better!’ However, I argue, either there is some interest at stake in knowing or there is not. If there is not, then there is no irresponsibility. If there (...) is, it is either the inquirer's interests—in which case it is a prudential shortcoming—or someone else's interests are at stake—in which case it is a moral shortcoming. In no case, I argue, is there any need to postulate a form of normativity in epistemology other than the traditional epistemological norm that one's attitudes should fit the evidence one has. (shrink)

One prevalent type of slippery slope argument has the following form: (1) by doing some initial act now, we will bring it about that we subsequently do some more extreme version of this act, and (2) we should not bring it about that we do this further act, therefore (3) we should not do the initial act. Such arguments are frequently regarded as mistaken, often on the grounds that they rely on speculative or insufficiently strong empirical premises. In this article (...) I point out another location at which these arguments may go wrong: I argue that, in their standard form, the truth of their empirical premises constitutes evidence for the falsity of their normative premises. If we will, as predicted, do the further act in the future, this gives us at least a prima facie reason to believe that the performance of this further act would be good, and thus something we should try to bring about. I end by briefly assessing the dialectic implications of my argument. I delineate a subset of slippery slope arguments against which my objection may be decisive, consider how the proponents of such arguments may evade my objection by adding further premises, and examine the likely plausibility of these additional premises. (shrink)

Assume that it is your evidence that determines what opinions you should have. I argue that since you should take peer disagreement seriously, evidence must have two features. (1) It must sometimes warrant being modest: uncertain what your evidence warrants, and (thus) uncertain whether you’re rational. (2) But it must always warrant being guided: disposed to treat your evidence as a guide. Surprisingly, it is very difficult to vindicate both (1) and (2). But diagnosing why this is so leads to (...) a proposal—Trust—that is weak enough to allow modesty but strong enough to yield many guiding features. In fact, I claim that Trust is the Goldilocks principle—for it is necessary and sufficient to vindicate the claim that you should always prefer to use free evidence. Upshot: Trust lays the foundations for a theory of disagreement and, more generally, an epistemology that permits self-doubt—a modest epistemology. (shrink)

The question I consider is this: -/- The Question: Can two people–who are, and realize they are, intellectually virtuous to about the same degree–both be rational in continuing knowingly to disagree after full disclosure (by each to the other of all the relevant evidence they can think of) while at the same time thinking that the other may well be rational too? -/- I distinguish two kinds of rationality–internal and external–and argue in section 1 that, whichever kind we have in (...) mind, the answer to The Question is ‘yes’ (though that positive answer is less wholehearted in the case of external rationality). Then, in section 2, I briefly make some more general remarks about when discovering a disagreement provides a defeater and when it doesn't. In the final section, I consider an important objection to the answer given in section 1 to The Question. (shrink)

People sometimes try to call others’ beliefs into question by pointing out the contingent causal origins of those beliefs. The significance of such ‘Etiological Challenges’ is a topic that has started attracting attention in epistemology. Current work on this topic aims to show that Etiological Challenges are, at most, only indirectly epistemically significant, insofar as they bring other generic epistemic considerations to the agent’s attention. Against this approach, we argue that Etiological Challenges are epistemically significant in a more direct and (...) more distinctive way. An Etiological Challenge prompts the agent to assess whether her beliefs result from practices of indoctrination, and whether she should reduce confidence in those beliefs, given the anti-reliability of indoctrination as a method of belief-acquisition. Our analysis also draws attention to some of the ways in which epistemic concerns interact with political issues—e.g. relating to epistemic injustice, identity-based discrimination, and segregation—when we’re thinking about the contingent causal origins of our beliefs. (shrink)

The “Evidentialist Dictum” says we must believe what our evidence supports, and the “Fallibility Norm” says we must take our fallibility into account when managing our beliefs. This paper presents a problem for the Evidentialist Dictum based in the Fallibility Norm and a particular conception of evidential support. It then addresses two novel Evidentialist responses to this problem. The first response solves the problem by claiming that fallibility information causes “evidence-loss.” In addition to solving the problem, this response appears to (...) explain what’s wrong with certain illegitimate dismissals of misleading evidence. However, this explanation opens it up to objections. Next, I consider and pose challenges to an Evidentialist strategy that attempts to solve the problem by converting accounts of fallibility’s epistemic significance for rational belief into principles of evidential support. I conclude by sketching a solution that allows us to capture what’s true in the Evidentialist Dictum and the Fallibility Norm. (shrink)

Moorean arguments are a popular and powerful way to engage highly revisionary philosophical views, such as nihilism about motion, time, truth, consciousness, causation, and various kinds of skepticism (e.g., external world, other minds, inductive, global). They take, as a premise, a highly plausible first-order claim (e.g., cars move, I ate breakfast before lunch, it’s true that some fish have gills) and conclude from it the falsity of the highly revisionary philosophical thesis. Moorean arguments can be used against nihilists in ethics (...) (error theorists), too. Recently, error theorists have recognized Moorean arguments as a powerful challenge and have tried to meet it. They’ve argued that moral Moorean premises seem highly credible to us, but aren’t, by offering various debunking explanations. These explanations all appeal to higher-order evidence—evidence of error in our reasoning. I argue that drawing attention to higher-order evidence is a welcome contribution from error theorists, but that the higher-order evidence actually counts further against error theoretic arguments—including their debunking explanations—and further in favor of Moorean arguments and the commonsense views they support. Along the way I answer a few prominent objections to Moorean arguments: that they are objectionably question-begging, rely on categorizing some facts as “Moorean Facts”, and that reports of one’s credence in a proposition bears no interesting relation to that proposition’s credibility. (shrink)

What should we do when faced with powerful theoretical arguments that support a severe change in our personal beliefs and commitments? For example, what should new parents do when confronted by unanswered anti-natalist arguments, or two lovers vexed by social theory that apparently undermines love? On the one hand, it would be irrational to ignore theory just because it’s theory; good theory is evidence, after all. On the other hand, factoring in theory can be objectifying, or risks unraveling one's life, (...) fracturing one's identity or social relations. Sometimes, then, following the evidence where it apparently leads would mean not merely changing what we think but who we are. Some might say that there’s something right about the thought that theory can bear on what we ought to believe, it’s just that when we work with full beliefs, only then do we seriously risk having to substantially alter our doxastic economy when pressed by exceptional theoretical arguments. When we work with partial beliefs, however, this risk is greatly diminished. Others will say that we can advocate or champion revisionary positions whilst rationally retaining our pre-theoretical personal convictions. Still others will argue that we should adopt a Moorean posture towards the revisionary arguments. I argue that each response is inadequate, and argue instead that we are permitted to bracket certain kinds of theoretical evidence against our beliefs because of the personal and ethical risks born out of giving them serious consideration. In turn, some of philosophy's doxastic influence is constrained by its attendant ethical risks: the personal enjoys a partial insulation from the theoretical. I close by addressing what this means for practicing philosophers. (shrink)

The question of the morality of abortion has long been the subject of intense, sometimes acrimonious debate. Even people within the same religious or philosophical tradition often disagree on the issue. For example, there are Christians who are “pro- choice” and there are Christians who are “pro-life.” Both sides marshal biblical, theological, and philosophical arguments in support of their positions. The substance of the abortion debate seems to reduce to one tricky question: when does personhood begin? Christian experts in various (...) fields, such as theology, biblical studies, ethics, and philosophy, have protracted disagreements over this question. In this article we will apply insights from the current literature on epistemic peer disagreement to the abortion issue. We will assume that there is only one correct answer to the abortion question. However, after making a crucial distinction between rationality as understood by internalists versus externalists, we will argue that there is more than one rational answer to the abortion question, since there is more than one rational way to weight evidence. We will conclude that, in a case of disagreement between two Christians who are epistemic peers with regards to the morality of abortion, both parties can be rational in adhering to their respective positions, but that this does not entail or even support ethical relativism. (shrink)

Debunking arguments use empirical evidence about our moral beliefs - in particular, about their causal origins, or about how they depend on various causes - in order to reach an epistemic conclusion about the trustworthiness of such beliefs. In this thesis, I investigate the scope and limits of debunking arguments, and their implications for what we should believe about morality. I argue that debunking arguments can in principle work - they are based on plausible epistemic premises, and at least some (...) of them avoid putative problems concerning regress and redundancy. However, I also argue that some debunking arguments fall short because they are insufficiently supported by the empirical evidence. By considering different objections, analyses, and a case study, I explore the conditions for a successful debunking argument. (shrink)

The purpose of this paper is to illustrate, formally, an ambiguity in the exercise of political influence. To wit: A voter might exert influence with an eye toward maximizing the probability that the political system (1) obtains the correct (e.g. just) outcome, or (2) obtains the outcome that he judges to be correct (just). And these are two very different things. A variant of Condorcet's Jury Theorem which incorporates the effect of influence on group competence and interdependence is developed. Analytic (...) and numerical results are obtained, the most important of which is that it is never optimal--from the point-of-view of collective accuracy--for a voter to exert influence without limit. He ought to either refrain from influencing other voters or else exert a finite amount of influence, depending on circumstance. Philosophical lessons are drawn from the model, to include a solution to Wollheim's "Paradox in the Theory of Democracy". (shrink)

Article Summary. The epistemology of disagreement studies the epistemically relevant aspects of the interaction between parties who hold diverging opinions about a given subject matter. The central question that the epistemology of disagreement purports to answer is how the involved parties should resolve an instance of disagreement. Answers to this central question largely depend on the epistemic position of each party before disagreement occurs. Two parties are equally positioned from an epistemic standpoint—namely, they are epistemic peers—to the extent that they (...) have roughly equal access to the evidence and comparable intellectual resources. When one party is epistemically better positioned than the other—that is, when one is an epistemic superior—it is widely agreed that this party should retain their belief while the other party—the epistemic inferior—should revise their opinion in the direction of what the epistemic superior believes. Addressing the central question is a complex task when the disagreeing parties are epistemic peers. Three main answers can be distinguished. Conciliatory answers mandate that both parties revise—i.e. lower their confidence in—their beliefs upon the occurrence of peer disagreement. Steadfast answers allow both parties to retain their respective beliefs, thereby committing them to demote the epistemic position of the interlocutor. The third group of answers suggests that the solution to peer disagreement depends on whether either party is highly justified in holding their belief. If either party is highly justified, then it is rational that this party retains its view. If neither party is highly justified, both should revise. The epistemology of disagreement addresses further important questions such as: whether the occurrence of disagreement opens the doors to skepticism and/or relativism; what the consequences of epistemic disagreement on intellectual character are; what laypeople should do when experts disagree with each other; and whether disagreement among groups can be treated in the same way as disagreement among individuals. (shrink)

Politics is rife with motivated cognition. People do not dispassionately engage with the evidence when they form political beliefs; they interpret it selectively, generating justifications for their desired conclusions and reasons why contrary evidence should be ignored. Moreover, research shows that epistemic ability (e.g. intelligence and familiarity with evidence) is correlated with motivated cognition. Bjørn Hallsson has pointed out that this raises a puzzle for the epistemology of disagreement. On the one hand, we typically think that epistemic ability in an (...) interlocutor gives us reason to downgrade our belief upon learning that we disagree. On the other hand, if our interlocutor is under the sway of motivated cognition, then we have reason to discount his opinion. In this paper, I argue that Hallsson's puzzle is solved by adopting a Bayesian approach to disagreement. If an interlocutor is under the sway of motivated cognition, his disagreement should not affect our beliefs--no matter his ability. Because we implicitly and to high accuracy know his beliefs before he reveals them to us, disagreement provides us with no new information on which to conditionalize. I advance a model which accommodates the motivated cognition dynamic and other key epistemic features of disagreement. (shrink)

Formally-inclined epistemologists often theorize about ideally rational agents--agents who exemplify rational ideals, such as probabilistic coherence, that human beings could never fully realize. This approach can be defended against the well-know worry that abstracting from human cognitive imperfections deprives the approach of interest. But a different worry arises when we ask what an ideal agent should believe about her own cognitive perfection (even an agent who is in fact cognitively perfect might, it would seem, be uncertain of this fact). Consideration (...) of this question reveals an interesting feature of the structure of our epistemic ideals: for agents with limited information, our epistemic ideals turn out to conflict with one another. (shrink)

What is it that we are doing when we make ethical claims and judgments, such as the claim that we morally ought to assist refugees? This dissertation introduces and defends a novel theory of ethical thought and discourse. I begin by identifying the surface features of ethical thought and discourse to be explained, including the realist and cognitivist (i.e. belief-like) appearance of ethical judgments, and the apparent close connection between making a sincere ethical judgment and being motivated to act on (...) it. I examine prominent attempts to explain these features, with a focus on recent ‘hybrid’ theories combining elements of expressivism and cognitivism. Despite their initial promise, I argue that extant hybrid theories are nevertheless committed to problematic semantic, metasemantic, or pragmatic assumptions. I then discuss what I take to be the strongest existing option, ethical neo-expressivism (Bar-On and Chrisman, 2009; Bar-On, Chrisman, and Sias, 2014), and develop it into an explicitly hybrid theory proposing that ethical judgments incorporate both motivationally-charged affective states and moral beliefs. I then supplement this account with a theory of the proper function (following Millikan, 1984) of ethical claims and judgments, arguing that they function simultaneously to track the morally salient features of social situations, and to coordinate our behavior around these features. Finally, I defend one of the cognitivist commitments of the theory – namely, that objective moral knowledge is possible – by applying recent work on the epistemology of fundamental or ‘core’ intellectual commitments (Lynch, 2012; Pritchard, 2016) to the moral realm. (shrink)

This entry addresses the nature and epistemological role of intuition by considering the following questions: (1) What are intuitions?, (2) What roles do they serve in philosophical (and other “armchair”) inquiry?, (3) Ought they serve such roles?, (4) What are the implications of the empirical investigation of intuitions for their proper roles?, and (5) What is the content of intuitions prompted by the consideration of hypothetical cases?

This article examines the central epistemological issues tied to the recognition of disagreement.

Contemporary epistemology of religion may conveniently be treated as adebate over whether evidentialism applies to thebelief-component of religious faith, or whether we should insteadadopt a more permissive epistemology. Here evidentialism is theinitially plausible position that a belief is justified only if``it is proportioned to the evidence''. For example, supposea local weather forecaster has noticed that over the two hundred yearssince records began a wetter than average Winter is followed in 85% ofcases by a hotter than average Summer. Then, assuming for (...) simplicitythat the records are reliable, the forecaster is justified in believingwith less than full confidence that this Winter, which is wetter thanaverage, will be followed by a hotter than average Summer. Butevidentialism implies that it would not be justified to have fullbelief, that is belief with 100% confidence. Again, consider someonewho has a hunch that this Summer will be hotter than averagebut cannot justify that hunch further. Hunches are not consideredevidence, so the belief is not considered justified. If, however, thehuncher can cite a good track record of hunches about the weather thathave turned out correct then the belief would be consideredjustified. For although hunches are not considered evidence, memoriesabout past hunches are, as are the observations that corroborated thepast hunches. (shrink)

Abstract. This paper argues that the “Argument from Moral Peer Disagreement” fails to make a case for widespread moral skepticism. The main reason for this is that the argument rests on a too strong assumption about the normative significance of peer disagreement (and higher-order evidence more generally). In order to demonstrate this, I distinguish two competing ways in which one might explain higher-order defeat. According to what I call the “Objective Defeat Explanation” it is the mere possession of higher-order evidence (...) that explains defeat. I argue that this type of explanation is problematic and that it at best collapses into another explanation I call the “Subjective Defeat Explanation”. According to this explanation, it is coming to believe that one’s belief fails to be rational that explains defeat. Then I go on to argue that the Subjective Defeat Explanation is able to provide a straightforward explanation of higher-order defeat but that it entails that peer disagreement (and higher-order evidence more generally) only contingently gives rise to defeat, and importantly, that the condition it is contingent upon is very often not satisfied when it comes to moral peer disagreement specifically. As a result, it appears that moral knowledge is seldom threatened by moral peer disagreement. (shrink)

In this introductory chapter, I first offer an overview of the two themes addressed in the present collection - namely, disagreement and skepticism - and their connection, then present the purpose and content of the volume.

I consider here the issue of whether and to what extent moral truths are absolute. My aim is to raise some new considerations in favor of moral relativism: the thesis that some moral statements can vary in truth-value depending on the moral standards at issue.1 2 This paper has three major components. First, I describe a new puzzle concerning the possibility of moral knowledge in light of expert disagreement. I argue that the best solution to this puzzle requires moral relativism. (...) Second, I develop a notion of a moral standard that incorporates recent developments in moral psychology, including work by.. (shrink)

We introduce a family of rules for adjusting one's credences in response to learning the credences of others. These rules have a number of desirable features. 1. They yield the posterior credences that would result from updating by standard Bayesian conditionalization on one's peers' reported credences if one's likelihood function takes a particular simple form. 2. In the simplest form, they are symmetric among the agents in the group. 3. They map neatly onto the familiar Condorcet voting results. 4. They (...) preserve shared agreement about independence in a wide range of cases. 5. They commute with conditionalization and with multiple peer updates. Importantly, these rules have a surprising property that we call synergy - peer testimony of credences can provide mutually supporting evidence raising an individual's credence higher than any peer's initial prior report. At first, this may seem to be a strike against them. We argue, however, that synergy is actually a desirable feature and the failure of other updating rules to yield synergy is a strike against them. (shrink)

In this paper, I aim to do three things. First, I introduce the distinction between the Uniqueness Thesis (U) and what I call the Conditional Uniqueness Thesis (U*). Second, I argue that despite their official advertisements, some prominent uniquers effectively defend U* rather than U. Third, some influential considerations that have been raised by the opponents of U misfire if they are interpreted as against U*. The moral is that an appreciation of the distinction between U and U* helps to (...) clarify the contours of the uniqueness debate and to avoid a good deal of talking past each other. (shrink)

I argue with my friends a lot. That is, I offer them reasons to believe all sorts of philosophical conclusions. Sadly, despite the quality of my arguments, and despite their apparent intelligence, they don’t always agree. They keep insisting on principles in the face of my wittier and wittier counterexamples, and they keep offering their own dull alleged counterexamples to my clever principles. What is a philosopher to do in these circumstances? (And I don’t mean get better friends.) One popular (...) answer these days is that I should, to some extent, defer to my friends. If I look at a batch of reasons and conclude p, and my equally talented friend reaches an incompatible conclusion q, I should revise my opinion so I’m now undecided between p and q. I should, in the preferred lingo, assign equal weight to my view as to theirs. This is despite the fact that I’ve looked at their reasons for concluding q and found them wanting. If I hadn’t, I would have already concluded q. The mere fact that a friend (from now on I’ll leave off the qualifier ‘equally talented and informed’, since all my friends satisfy that) reaches a contrary opinion should be reason to move me. Such a position is defended by Richard Feldman (2006a, 2006b), David Christensen (2007) and Adam Elga (forthcoming). This equal weight view, hereafter EW, is itself a philosophical position. And while some of my friends believe it, some of my friends do not. (Nor, I should add for your benefit, do I.) This raises an odd little dilemma. If EW is correct, then the fact that my friends disagree about it means that I shouldn’t be particularly confident that it is true, since EW says that I shouldn’t be too confident about any position on which my friends disagree. But, as I’ll argue below, to consistently implement EW, I have to be maximally confident that it is true. So to accept EW, I have to inconsistently both be very confident that it is true and not very confident that it is true. This seems like a problem, and a reason to not accept EW.. (shrink)

Disagreement among experts is a central topic in social epistemology. What should an expert do when confronted with the different opinion of an epistemic peer? Possible answers include the steadfast view, the abstemious view, and moderate conciliatory views, which specify criteria for belief change when a peer’s different opinion is encountered. The practice of Delphi techniques in healthcare, medicine, and social sciences provides a real-life case study of expert disagreement, where disagreement is gradually transformed into consensus. An analysis of Delphi (...) shows that moderate conciliatory views are descriptively more adequate than rival views. However, it also casts doubt on whether the debate in social epistemology is explanatory relevant vis-à-vis real life cases of expert disagreement, where consensus replaces truth, and acceptance is more explanatorily relevant than belief. (shrink)

The philosophical path that I propose finds its origin in a properly metaethical questioning. It was first of all a question about the meaning of our moral statements by considering a defense of some kind of moral realism according to which our moral judgments would refer to a “moral reality” which would make it possible to determine their truth or their falsity. However, the realistic interpretation of moral judgments poses many difficulties from a psychological, an ontological and an epistemological point (...) of view. The central idea of this thesis was to explore these difficulties in order to consider the possibility of defending a form of moral realism. Nevertheless, this exploration – which constitutes the first part of this work – led me to a dead end in which all metaethical positions appeared to me as interesting as they were unsatisfactory. Faced with this situation, a new problem emerged to me as central: the disagreement between epistemic peers in philosophy. Since all metaethical positions are, even today, defended by experts in the field, it seemed to me essential to treat this difficulty with the intuition that a skeptical solution would be necessary. But this first turnaround was also unsatisfying, and rather than a skeptical conclusion it led me to shift my questioning to philosophy itself: what is philosophy? what can we expect from it? Perhaps my conception of philosophy – a search for truth based on argumentation – was at the origin of these successive dissatisfactions. I thus explore, in the last chapter, another way of approaching philosophy. Maybe it's not about looking for solutions to problems, like in science, maybe it’s about dealing with individual embarrassments which, at best, could just disappear. Thus “success” in philosophy would only be its abandonment – as an individual practice, and not as a discipline – through the disappearance of our philosophical embarrassments. In the end, I must admit that I do not have the means to defend such a conception of philosophy, but I can only note that all this work on moral realism, disagreement and philosophy was, for me, a way to make my philosophical embarrassment disappear. This is how, far from its starting point, the philosophical path that was mine ended. (shrink)

I consider whether evolutionary explanations can debunk our moral beliefs. Most contemporary discussion in this area is centred on the question of whether debunking implications follow from our ability to explain elements of human morality in terms of natural selection, given that there has been no selection for true moral beliefs. By considering the most prominent arguments in the literature today, I offer reasons to think that debunking arguments of this kind fail. However, I argue that a successful evolutionary debunking (...) argument can be constructed by appeal to the suggestion that our moral outlook reflects arbitrary contingencies of our phylogeny, much as the horizontal orientation of the whale’s tail reflects its descent from terrestrial quadrupeds. An introductory chapter unpacks the question of whether evolutionary explanations can debunk our moral beliefs, offers a brief historical guide to the philosophical discussion surrounding it, and explains what I mean to contribute to this discussion. Thereafter follow six chapters and a conclusion. The six chapters are divided into three pairs. The first two chapters consider what contemporary scientific evidence can tell us about the evolutionary origins of morality and, in particular, to what extent the evidence speaks in favour of the claims on which debunking arguments rely. The next two chapters offer a critique of popular debunking arguments that are centred on the irrelevance of moral facts in natural selection explanations. The final chapters develop a novel argument for the claim that evolutionary explanations can undermine our moral beliefs insofar as they show that our moral outlook reflects arbitrary contingencies of our phylogeny. A conclusion summarizes my argument and sets out the key questions that arise in its wake. (shrink)

One of Mill’s main arguments for free speech springs from taking disagreement as an epistemically valuable resource for fallible thinkers. Contemporary conciliationist treatments of disagreement spring from the same motivation, but end up seeing the epistemic implications of disagreement quite differently. Conciliationism also encounters complexities when transposed from the 2-person toy examples featured in the literature to the public disagreements among groups that give the issue much of its urgency. Group disagreements turn out to be in some ways more powerful (...) defeaters of rational belief, even when opposing groups are comparable in size and epistemic credentials. And conciliationism also shows us why determining the rational response to these disagreements can in certain cases (e.g. politics) be a particularly difficult and nuanced matter. (shrink)

Responding rationally to the information that others disagree with one’s beliefs requires assessing the epistemic credentials of the opposing beliefs. Conciliatory accounts of disagreement flow in part from holding that these assessments must be independent from one’s own initial reasoning on the disputed matter. I argue that this claim, properly understood, does not have the untoward consequences some have worried about. Moreover, some of the difficulties it does engender must be faced by many less conciliatory accounts of disagreement.

Many philosophers regard the persistence of philosophical disputes as symptomatic of overly ambitious, ill-founded intellectual projects. There are indeed strong reasons to believe that persistent disputes in philosophy (and more generally in the discourse at large) are pointless. We call this the pessimistic view of the nature of philosophical disputes. In order to respond to the pessimistic view, we articulate the supporting reasons and provide a precise formulation in terms of the idea that the best explanation of persistent disputes entails (...) that they are pointless. We then show how to answer the pessimistic argument. Taking a well-known mathematical controversy as our paradigm example, we argue that some persistent disputes reflect substantive disagreements at the “meta-analytic” level, i.e., disagreements about the best way, among quite different candidates, to understand the topic at issue, and the best associated cluster of analytic truths one should accept concerning it. Moreover, our concrete example shows that such meta-analytic disagreements can in principle be settled and yield a genuine theoretical (as opposed to merely pragmatic) breakthrough. We conclude optimistically that persistent disputes can be an important means of fostering epistemic progress. (shrink)

In this paper, I respond to Jonathan Matheson's discussion of "Disagreement, Deference, and Religious Commitment.".

The paper critically discusses the dualism in the interpretation of the moral basis of public reason. We argue that in order to maintain the complementarity of both liberal and democratic values within the debate on public reason, the arguments from liberty and from civic friendship cannot be considered in isolation. With regard to the argument from liberty, we contend that because the idea of natural liberty is an indispensable starting point of liberal theory, no explanation of the justification of political (...) power can do without it. In particular, we focus on the requirement of reasonableness and show that we should retain the epistemic aspect of the reasonableness of persons. The main reason for this is to be found in the criterion of reciprocity which provides the deepest justification of the respect for people’s liberty – that is, the liberal aspect of liberal democracy. At the same time, however, we argue that reciprocity also provides the grounds for responding to the criticism that the essentially liberal approach fails to adequately take into consideration the role of political community. Because reciprocity may also be interpreted as being based on civic friendship, it provides the resources to respond to such criticism. It thus supplies the normative background also for the second, democratic pillar of public reason. We then critically examine the newly emerging approach built predominantly on the argument from civic friendship, arguing that by prioritising the civic friendship interpretation and, at times, tending to completely abandon the liberty-based one, it overlooks the indispensability of liberty-based considerations for the criterion of reciprocity. We conclude that in order to adequately capture the common liberal-democratic basis of public reason, both interpretations of reciprocity must be linked within a comprehensive account. (shrink)

This chapter covers contemporary work on disagreement, detailing both the conceptual and normative issues in play in the debates in mainstream analytic epistemology, and how these relate to religious diversity and disagreement. §1 examines several sorts of disagreement, and considers several epistemological issues: in particular, what range of attitudes a body of evidence can support, how to understand higher-order evidence, and who counts as an epistemic “peer”. §2 considers how these questions surface when considering disagreements over religion, including debates over (...) the nature of evidence and truth in religion, epistemic humility, concerns about irrelevant influences and about divine hiddenness, and arguments over exclusivism, inclusivism, and pluralism. Finally, §3 summarizes the contributors’ essays in this volume. (shrink)

This thesis is a collection of three self-contained papers on related themes in the area of formal and social epistemology. The first paper explores the possibility of measuring the coherence of a set with multiplicative averaging. It has been pointed out that all the existing probabilistic measures of coherence are flawed for taking the relevance between a set of propositions as the primary factor which determines the coherence of the set. What I show in this paper is that a group (...) of measures, namely the confirmation-based ones, can be saved from this problem if we adopt a nonlinear averaging function to measure the coherence of a set. The second paper discusses how people should conciliate in disagreements. Some epistemologists take linear averaging as the only way of conciliating and claim that conciliating leads to fallacious results. In the paper, I show that the problem is not conciliating, but taking linear averaging as the only way to conciliate. Since there is no reason for us to insist on conciliating with linear averaging, we can adopt nonlinear averaging functions for conciliating and thereby avoid the formal deficiencies. The third paper focuses on the pragmatic results of taking conciliating as a general strategy in disagreements. There is a potential dilemma about conciliating: if everyone always conciliates, it is likely for an epistemic bubble to arise. If everyone refuses to conciliate, an epistemic echo chamber may appear. A possible way of solving the dilemma is to develop a diachronic strategy which tells people how to both conciliate and update their estimate of their interlocutors’ reliability. Although the three papers differ in the subject, they jointly offer some unifying reflections on the way we approach philosophical problems with formal tools. From 5 the first two papers, we see that a formal analysis of a philosophical position is incomplete if philosophers fail to consider a sufficiently wide range of formal tools. The third paper, on the contrary, shows that we should change the ordinary way of modelling a notion if required. This thesis concludes by proposing a pluralistic view of formal methods in formal epistemology. (shrink)

Many contributors of the debate about knowledge by testimony concentrate on the problem of justification. In my paper I will stress a different point – the concept of testimony itself. As a starting point I will use the definitional proposal of Jennifer Lackey. She holds that the concept of testimony should be regarded as entailing two aspects – one corresponding to the speaker, the other one to the hearer. I will adopt the assumption that we need to deal with both (...) aspects. Nevertheless, I will show that her concept – which suggests regarding testimony as an act of communication conveying information – is too broad and, therefore, I will end up with a different twofold definition. (shrink)

Richard Feldman’s “Reasonable Religious Disagreements” launched debates about the epistemic significance of disagreement that have been a dominant point of discussion in epistemology as of late. While most of these debates have been concerned with disagreement more generally, Feldman’s original focus was religious disagreement, and John Pittard returns the focus to religious disagreement in Disagreement, Deference, and Religious Commitment. Pittard’s book delves deeply into debates about the significance of disagreement with a foot in both epistemology and philosophy of religion. It (...) is the first book to look at these issues as they are being addressed within each of these sub-disciplines and is sure to be a significant contribution to the debates in both sub-fields. (shrink)

Disagreement is a ubiquitous feature of human life, and philosophers have dutifully attended to it. One important question related to disagreement is epistemological: How does a rational person change her beliefs (if at all) in light of disagreement from others? The typical methodology for answering this question is to endorse a steadfast or conciliatory disagreement norm (and not both) on a priori grounds and selected intuitive cases. In this paper, I argue that this methodology is misguided. Instead, a thoroughgoingly Bayesian (...) strategy is what's needed. Such a strategy provides conciliatory norms in appropriate cases and steadfast norms in appropriate cases. I argue, further, that the few extant efforts to address disagreement in the Bayesian spirit are laudable but uncompelling. A modelling, rather than a functional, approach gets us the right norms and is highly general, allowing the epistemologist to deal with (1) multiple epistemic interlocutors, (2) epistemic superiors and inferiors (i.e. not just epistemic peers), and (3) dependence between interlocutors. (shrink)

Much of the literature on the epistemology of disagreement focuses on the rational responses to disagreement, and to disagreement with an epistemic peer in particular. The Equal Weight View claims that in cases of peer disagreement each dissenting peer opinion is to be given equal weight and, in a case of two opposing equally-weighted opinions, each party should adopt the attitude which ‘splits the difference’. The Equal Weight View has been taken by both its critics and its proponents to have (...) quite drastic skeptical ramifications given contingent empirical facts that we are aware of regarding disagreements in philosophy, religion, science, and politics. In this paper,we begin by clarifying the central claims of the Equal Weight View (Section 2) and then examine two routes from the Equal Weight View to skepticism about such matters that have been explored in the literature. The first claims that our awareness of peers or experts who disagree with us about such issues requires that we abandon our beliefs on these issues (Section 3). The second claims that our awareness of merely possible peers or experts who disagree with us requires us to abandon our beliefs (Section 4). We find both routes from the Equal Weight View to a form of skepticism defective. However, there are nearby considerations, explored in Sections 5 and 6,which (for better or worse) do lead to at least some skeptical consequences for the Equal WeightView, albeit for different reasons. (shrink)