Online research in philosophy

What is the nature of rational disagreement? A number of philosophers have recently addressed this question by examining how we should respond to epistemic conflict with a so-called epistemic peer—that is, someone over whom you enjoy no epistemic advantage. Some say that you're rationally required to suspend judgment in these cases—thereby denying the very possibility of a certain kind of rational disagreement. Others say that it's permissible to retain your beliefs even in the face of epistemic conflict. By distinguishing between close peers and distant peers, I argue that it's rational to respond to different types of peers in different ways. I also argue that remote peers—a particularly distant kind of distant peer—provide us with an important lesson in epistemic humility.

I introduce a different framework for thinking about peer disagreement -- one that distinguishes sharply between epistemic rationality and evidential support. I then defend the view that conciliationism provides the right answer to, "What credences is it rational to adopt in cases of peer disagreement?" and that non-conciliationism provides the right answer to, "What credences does the evidence support in cases of peer disagreement?" I then spend the second half of the paper applying some distinctions within rationality -- global vs. local rational norms, wide-scope vs. narrow-scope rational norms -- to a defense of conciliationism against recent challenges by Tom Kelly and Brian Weatherson. I conclude by introducing what I think is an underdiscussed problem but a potentially fruitful one to think about: what is it rational to do relative to a set of mental states, some of which are beliefs or credences about rationality itself?

Note: New version MARCH 23.

Some philosophers believe that when epistemic peers disagree, each has an obligation to accord the other's assessment the same weight as her own. I first make the antecedent of this Equal-Weight View more precise, and then I motivate the View by describing cases in which it gives the intuitively correct verdict. Next I introduce some apparent counterexamples – cases of apparent peer disagreement in which, intuitively, one should not give equal weight to the other party's assessment. To defuse these apparent counterexamples, an advocate of the View might try to explain how they are not genuine cases of peer disagreement. I examine David Christensen's and Adam Elga's explanations and find them wanting. I then offer a novel explanation, which turns on a distinction between knowledge from reports and knowledge from direct acquaintance. Finally, I extend my explanation to provide a handy and satisfying response to the charge of self-defeat.

I develop a general framework with a rationality constraint that shows how coherently to represent and deal with second-order information about one's own judgmental reliability. It is a rejection of and generalization away from the typical Bayesian requirements of unconditional judgmental self-respect and perfect knowledge of one's own beliefs, and is defended by appeal to the Principal Principle. This yields consequences about maintaining unity of the self, about symmetries and asymmetries between the first- and third-person, and a principled way of knowing when to stop second-guessing oneself. Peer disagreement is treated as a special case where one doubts oneself because of news that an intellectual equal disagrees. This framework, and variants of it, imply that the typically stated belief that an equally reliably peer disagrees is incoherent, and thus that pure rationality constraints without further substantive information cannot give an answer as to what to do. The framework also shows that treating both ourselves and others as thermometers in the disagreement situation does not imply the Equal Weight view.

My aim in this paper is to develop and defend a novel answer to a question that has recently generated a considerable amount of controversy. The question concerns the normative significance of peer disagreement. Suppose that you and I have been exposed to the same evidence and arguments that bear on some proposition: there is no relevant consideration which is available to you but not to me, or vice versa. For the sake of concreteness, we might picture.

There is an ancient, yet still lively, debate in moral epistemology about the epistemic significance of disagreement. One of the important questions in that debate is whether, and to what extent, the prevalence and persistence of disagreement between our moral intuitions causes problems for those who seek to rely on intuitions in order to make moral decisions, issue moral judgments, and craft moral theories. Meanwhile, in general epistemology, there is a relatively young, and very lively, debate about the epistemic significance of disagreement. A central question in that debate concerns peer disagreement: When I am confronted with an epistemic peer with whom I disagree, how should my confidence in my beliefs change (if at all)? The disagreement debate in moral epistemology has not been brought into much contact with the disagreement debate in general epistemology (though McGrath [2007] is an important exception). A purpose of this paper is to increase the area of contact between these two debates. In Section 1, I try to clarify the question I want to ask in this paper – this is the question whether we have any reasons to believe what I shall call “anti-intuitivism.” In Section 2, I argue that anti-intuitivism cannot be supported solely by investigating the mechanisms that produce our intuitions. In Section 3, I discuss an anti-intuitivist argument from disagreement which relies on the so-called “Equal Weight View.” In Section 4, I pause to clarify the notion of epistemic parity and to explain how it ought to be understood in the epistemology of moral intuition. In Section 5, I return to the anti-intuitivist argument from disagreement and explain how an apparently-vulnerable premise of that argument may be quite resilient. In Section 6, I introduce a novel objection against the Equal Weight View in order to show how I think we can successfully resist the anti-intuitivist argument from disagreement.

You and I have been colleagues for ten years, during which we have tirelessly discussed the reasons both for and against the existence of God. There is no argument or piece of evidence bearing directly on this question that one of us is aware of that the other is not—we are, then, evidential equals1 relative to the topic of God’s existence.2 There is also no cognitive virtue or capacity, or cognitive vice or incapacity, that one of us possesses that the other does not—we are, then, also cognitive equals relative to the question at issue.3 Given this evidential and cognitive equality, combined with the fact that we have fully disclosed to one another all of our reasons and arguments relative to this topic, we are epistemic peers with respect to the question whether God exists.4 Yet despite the symmetry of our epistemic positions, we deeply disagree about the answer to this question. What response does rationality require in such a case, where epistemic peers disagree over a question despite there being no apparent asymmetries between them?5 There are two main answers to this question in the recent literature. First, there is the view of the nonconformists, who maintain that one can continue to rationally believe that p despite the fact that one’s epistemic peer explicitly believes that not-p, even when one does not have a reason independent of the disagreement itself to prefer one’s own belief.6 Otherwise put, nonconformists argue that there can be reasonable disagreement among epistemic peers. There are two central explanations of the nonconformist response to peer disagreement.7 On the one hand, there is the egocentric view, which holds that I am justified in giving my belief extra weight8 in the face of peer disagreement because the belief in question is mine.9 On the other hand, there is the correct reasoning view, according to which I am justified in giving my belief extra weight in the face of peer disagreement because the belief in question is in fact the product of correct reasoning.10 Despite these....

This paper assesses the comparative reliability of two beliefrevision rules relevant to the epistemology of disagreement, the Equal Weight and Stay the Course rules. I use two measures of reliability for probabilistic belief-revision rules, Calibration and Brier Scoring, to give a precise account of epistemic peerhood and epistemic reliability. On the Calibration measure of reliability, epistemic peerhood is easy to come by, and employing the Equal Weight rule in the case of peer disagreement generally renders you less reliable than Staying the Course. On the Brier-Score measure of reliability, epistemic peerhood is much more difficult to come by, but employing the Equal Weight rule in the case of peer disagreement always renders you more reliable than Staying the Course. I conclude with some lessons we can draw from these formal results for the normative issue of rational belief-change in the face of peer disagreement, foreshadowing part II of my work on this topic, “On the Rationality of Belief-Invariance in Light of Peer Disagreement.”.

This paper considers two questions. First, what is the scope of the Equal Weight View? Is it the case that meeting halfway is the uniquely rational method of belief-revision in all cases of known peer disagreement? The answer is no. It is sometimes rational to maintain your own opinion in the face of peer disagreement. But this leaves open the possibility that the Equal Weight View is indeed sometimes the uniquely rational method of belief revision. Precisely what is the skeptical import of this fact; is it the case that some form of skepticism triumphs in such cases? The answer to this question is also no. As it turns out, the situations in which it is most plausible that the Equal Weight view is a rational requirement are the ones in which meeting halfway with a disagreeing peer brings you closer to, and not farther from, knowledge. I argue for these theses in a novel way; by looking at the comparative reliability of belief-invariance and meeting halfway using measures of reliability for degrees of belief, and by drawing normative conclusions from such results. The conclusions here can have the effect of reframing the entire debate in the epistemology of disagreement.

Contemporary epistemology of peer disagreement has largely focused on our immediate normative response to prima facie instances of disagreement. Whereas some philosophers demand that we should withhold judgment (or moderate our credences) in such cases, others argue that, unless new evidence becomes available, disagreement at best gives us reason to demote our interlocutor from his peer status. But what makes someone an epistemic peer in the first place? This question has not received the attention it deserves. I begin by surveying different notions of ‘epistemic peer’ that have been peddled in the contemporary literature, arguing that they tend to build normative assumptions about the correct response to disagreement into the notion of peerhood. Instead, I argue, epistemic peerhood needs to be taken seriously in its own right. Importantly, for epistemic agents to count as peers, they should exhibit a comparable degree of reflective awareness of the character and limitations of their own knowledge.