Disagreement is common: even informed, intelligent, and generally reasonable people often come to different conclusions when confronted with what seems to be the same evidence. Can the competing conclusions be reasonable? If not, what can we reasonably think about the situation? This volume examines the epistemology of disagreement. Philosophical questions about disagreement arise in various areas, notably politics, ethics, aesthetics, and the philosophy of religion: but this will be the first book focusing on the general epistemic issues arising from informed (...) disagreement. Ten leading philosophers offer specially written essays which together will offer a starting-point for future work on this topic. (shrink)

We often find that beliefs we hold are in conflict with the beliefs of epistemic peers, individuals who are just as intelligent, just as well-informed, and just as scrupulous in forming their beliefs as we are. Is it permissible to maintain our beliefs in the face of such disagreement? It is argued here that continued belief in these circumstances is not epistemically permissible, and that this has striking consequences for the practice of philosophy: we cannot reasonably hold on to our (...) philosophical views. (shrink)

I treat you as a thermometer when I use your belief states as more or less reliable indicators of the facts. Should I treat myself in a parallel way? Should I think of the outputs of my faculties and yours as like the readings of two thermometers the way a third party would? I explore some of the difficulties in answering these questions. If I am to treat myself as well as others as thermometers in this way, it would appear (...) that I cannot reasonably trust my own convictions over yours unless I have antecedent reason to suppose that I am more likely than you to get things right. I appeal to some probabilistic considerations to suggest that our predicament as thermometers might not actually be as bad as it seems. (shrink)

I treat you as a thermometer when I use your belief states as more or less reliable indicators of the facts. Should I treat myself in a parallel way? Should I think of the outputs of my faculties and yours as like the readings of two thermometers the way a third party would? I explore some of the difficulties in answering these questions. If I am to treat myself as well as others as thermometers in this way, it would appear (...) that I cannot reasonably trust my own convictions over yours unless I have antecedent reason to suppose that I am more likely than you to get things right. I appeal to some probabilistic considerations to suggest that our predicament as thermometers might not actually be as bad as it seems. (shrink)

How should one react when one has a belief, but knows that other people—who have roughly the same evidence as one has, and seem roughly as likely to react to it correctly—disagree? This paper argues that the disagreement of other competent inquirers often requires one to be much less confident in one’s opinions than one would otherwise be.

Plausibly, you should believe what your total evidence supports. But cases of misleading higher-order evidence—evidence about what your evidence supports—present a challenge to this thought. In such cases, taking both first-order and higher-order evidence at face value leads to a seemingly irrational incoherence between one’s first-order and higher-order attitudes: you will believe P, but also believe that your evidence doesn’t support P. To avoid sanctioning tension between epistemic levels, some authors have abandoned the thought that both first-order and higher-order evidence (...) have rational bearing. This sacrifice is both costly and unnecessary. We propose a principle, Evidential Calibration, which requires rational agents to accommodate first-order evidence correctly, while allowing rational uncertainty about what to believe. At the same time, it rules out irrational tensions between epistemic levels. We show that while there are serious problems for some views on which we can rationally believe, “P, but my evidence doesn’t support P”, Evidential Calibration avoids these problems. An important upshot of our discussion is a new way to think about the relationship between epistemic levels: why first-order and higher-order attitudes should generally be aligned, and why it is sometimes—though not always—problematic when they diverge. (shrink)

Philosophers often find themselves in disagreement with contemporary philosophers they know full well to be their epistemic superiors on the topics relevant to the disagreement. This looks epistemically irresponsible. I offer a detailed investigation of this problem of the reflective epistemic renegade. I argue that although in some cases the renegade is not epistemically blameworthy, and the renegade situation is significantly less common than most would think, in a troublesome number of cases in which the situation arises the renegade is (...) blameworthy in her disagreement with recognized epistemic superiors. I also offer some thoughts on what it would mean for philosophical practice for us to refrain from being renegades. Finally, I show how a new kind of radical skepticism emerges from modest theses regarding the renegade. (shrink)

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)

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)

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)

Disagreement is common: even informed, intelligent, and generally reasonable people often come to different conclusions when confronted with what seems to be the same evidence. Can the competing conclusions be reasonable? If not, what can we reasonably think about the situation? This volume examines the epistemology of disagreement. Philosophical questions about disagreement arise in various areas, notably politics, ethics, aesthetics, and the philosophy of religion: but this will be the first book focusing on the general epistemic issues arising from informed (...) disagreement. Ten leading philosophers offer specially written essays which together will offer a starting-point for future work on this topic. (shrink)

This is a collective study of the epistemic significance of disagreement: twelve contributors explore rival responses to the problems that it raises for philosophy. They develop our understanding of epistemic phenomena that are central to any thoughtful engagement with others' beliefs.

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.

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)