It is common orthodoxy among internalists and externalists alike that knowledge is lost or defeated in situations involving misleading evidence of a suitable kind. But making sense of defeat has seemed to present a particular challenge for those who reject an internalist justification condition on knowledge. My main aim here is to argue that externalists ought to take seriously a view on which knowledge can be retained even in the face of strong seemingly defeating evidence. As an instructive example, I (...) first discuss whether a theory on which knowledge is belief that is safe from error has the resources for accommodating defeat. I argue that beliefs retained in defeat cases need not be unsafe or true in some accidental way. I then discuss externalist strategies for explaining why we have incorrect intuitions about defeat. The notion of an epistemically reasonable subject plays a central role in my theory. Reasonable subjects adopt general strategies that are good for acquiring true belief and knowledge across a wide range of normal cases, but stubbornly retaining belief in the face of new evidence does not reflect such policies. I argue that though the methods employed by subjects who fail to adjust their beliefs in defeat cases may be perfectly good, they are not good methods to adopt, as their adoption is accompanied by bad dispositions. What emerges is a view on which a subject can know despite being unreasonable, and despite failing to manifest dispositions to know across normal cases. Unreasonable subjects are genuinely criticisable, but like almost anything, knowledge can sometimes be achieved in the absence of a good general strategy. (shrink)

In this paper I will present a puzzle about epistemic akrasia, and I will use that puzzle to motivate accepting some non-standard views about the nature of epistemological judgment. The puzzle is that while it seems obvious that epistemic akrasia must be irrational, the claim that epistemic akrasia is always irrational amounts to the claim that a certain sort of justified false belief—a justified false belief about what one ought to believe—is impossible. But justified false beliefs seem to be possible (...) in any domain, and it’s hard to see why beliefs about what one ought to believe should be an exception. I will argue that when we get clearer about what sort of psychological state epistemic akrasia is, we can resolve the puzzle in favor of the intuitive view that epistemic akrasia is always irrational. (shrink)

Operational epistemology is, to a first approximation, the attempt to provide cognitive rules such that one is in principle always in a position to know whether one is complying with them. In Knowledge and its Limits, I argue that the only such rules are trivial ones. In this paper, I generalize the argument in several ways to more thoroughly probabilistic settings, in order to show that it does not merely demonstrate some oddity of the folk epistemological conception of knowledge. Some (...) of the generalizations involve a formal semantic framework for treating epistemic probabilities of epistemic probabilities and expectations of expectations. The upshot is that operational epistemology cannot work, and that knowledge-based epistemology has the right characteristics to avoid its problems. (shrink)

What is the role of consciousness in our mental lives? Declan Smithies argues here that consciousness is essential to explaining how we can acquire knowledge and justified belief about ourselves and the world around us. On this view, unconscious beings cannot form justified beliefs and so they cannot know anything at all. Consciousness is the ultimate basis of all knowledge and epistemic justification.

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)

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)

You have higher-order uncertainty iff you are uncertain of what opinions you should have. I defend three claims about it. First, the higher-order evidence debate can be helpfully reframed in terms of higher-order uncertainty. The central question becomes how your first- and higher-order opinions should relate—a precise question that can be embedded within a general, tractable framework. Second, this question is nontrivial. Rational higher-order uncertainty is pervasive, and lies at the foundations of the epistemology of disagreement. Third, the answer is (...) not obvious. The Enkratic Intuition---that your first-order opinions must “line up” with your higher-order opinions---is incorrect; epistemic akrasia can be rational. If all this is right, then it leaves us without answers---but with a clear picture of the question, and a fruitful strategy for pursuing it. (shrink)

In everyday life and in science we acquire evidence of evidence and based on this new evidence we often change our epistemic states. An assumption underlying such practice is that the following EEE Slogan is correct: 'evidence of evidence is evidence' (Feldman 2007, p. 208). We suggest that evidence of evidence is best understood as higher-order evidence about the epistemic state of agents. In order to model evidence of evidence we introduce a new powerful framework for modelling epistemic states, Dyadic (...) Bayesianism. Based on this framework, we then discuss characterizations of evidence of evidence and argue for one of them. Finally, we show that whether the EEE Slogan holds, depends on the specific kind of evidence of evidence. (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)

A rational person doesn’t believe just anything. There are limits on what it is rational to believe. How wide are these limits? That’s the main question that interests me here. But a secondary question immediately arises: What factors impose these limits? A first stab is to say that one’s evidence determines what it is epistemically permissible for one to believe. Many will claim that there are further, non-evidentiary factors relevant to the epistemic rationality of belief. I will be ignoring the (...) details of alternative answers in order to focus on the question of what kind of rational constraints one’s evidence puts on belief. Our main question concerns how far epistemic permission and obligation can come apart.1 Suppose I am epistemically permitted to believe P, i.e., it would not be irrational for me to believe it. Am I thereby obliged to believe P, or are other options rationally available to me?2 Might I be equally rational in remaining agnostic about P, or even believing not-P? Or could even a slightly stronger or weaker degree of confidence be just as reasonable? (shrink)

Many have claimed that unspecific evidence sometimes demands unsharp, indeterminate, imprecise, vague, or interval-valued probabilities. Against this, a variant of the diachronic Dutch Book argument shows that perfectly rational agents always have perfectly sharp probabilities.

Normative Externalism argues that it is not important that people live up to their own principles. What matters, in both ethics and epistemology, is that they live up to the correct principles: that they do the right thing, and that they believe rationally. This stance, that what matters are the correct principles, not one's own principles, has implications across ethics and epistemology. In ethics, it undermines the ideas that moral uncertainty should be treated just like factual uncertainty, that moral ignorance (...) frequently excuses moral wrongdoing, and that hypocrisy is a vice. In epistemology, it suggests we need new treatments of higher-order evidence, and of peer disagreement, and of circular reasoning, and the book suggests new approaches to each of these problems. Although the debates in ethics and in epistemology are often conducted separately, putting them in one place helps bring out their common themes. One common theme is that the view that one should live up to one's own principles looks less attractive when people have terrible principles, or when following their own principles would lead to riskier or more aggressive action than the correct principles. Another common theme is that asking people to live up to their principles leads to regresses. It can be hard to know what action or belief complies with one's principles. And now we can ask, in such a case should a person do what they think their principles require, or what their principles actually require? Both answers lead to problems, and the best way to avoid these problems is to simply say people should follow the correct principles. (shrink)

Epistemic Permissivists face a special problem about the relationship between our first- and higher-order attitudes. They claim that rationality often permits a range of doxastic responses to the evidence. Given plausible assumptions about the relationship between your first- and higher-order attitudes, it can't be rational to adopt a credence on the edge of that range. But Permissivism says that, for some such range, any credence in that range is rational. Permissivism, in its traditional form, cannot be right. I consider some (...) new ways of developing Permissivism to avoid this argument, but each has problems of its own. (shrink)

For many epistemologists, and for many philosophers more broadly, it is axiomatic that rationality requires you to take the doxastic attitudes that your evidence supports. Yet there is also another current in our talk about rationality. On this usage, rationality is a matter of the right kind of coherence between one's mental attitudes. Surprisingly little work in epistemology is explicitly devoted to answering the question of how these two currents of talk are related. But many implicitly assume that evidence -responsiveness (...) guarantees coherence, so that the rational impermissibility of incoherence will just fall out of the putative requirement to take the attitudes that one's evidence supports, and so that coherence requirements do not need to be theorized in their own right, apart from evidential reasons. In this paper, I argue that this is a mistake, since coherence and evidence -responsiveness can in fact come into conflict. More specifically, I argue that in cases of misleading higher-order evidence, there can be a conflict between believing what one's evidence supports and satisfying a requirement that I call “inter-level coherence ”. This illustrates why coherence requirements and evidential reasons must be separated and theorized separately. (shrink)

Improbable knowing is knowing something even though it is almost certain on one’s evidence at the time that one does not know that thing. Once probabilities on the agent’s evidence are introduced into epistemic logic in a very natural way, it is easy to construct models of improbable knowing, some of which have realistic interpretations, for instance concerning agents like us with limited powers of perceptual discrimination. Improbable knowing is an extreme case of failure of the KK principle, that is, (...) of a case of knowing something even though one does not know at the time that one knows that thing. A generalization of the argument yields cases of improbable rationality, in which it is rational for one to do something even though it is almost certain on one’s evidence at the time that it is not rational for one to do that thing. When the models are elaborated to represent appearances and beliefs as well as knowledge, they turn out to contain Gettier cases. Neglect of the possibility of improbable knowing may cause some sceptical claims and claims of the non-closure of knowledge under competent deduction to look more plausible than they deserve to. A formal appendix explores the closely related question of the conditions under which a reflection principle is violated. The principle says that the evidential probability of a proposition conditional on the evidential probability of that proposition’s being c is itself c. (shrink)

Recent discussion of Vogel-style “bootstrapping” scenarios suggests that they provide counterexamples to a wide variety of epistemological theories. Yet it remains unclear why it’s bad for a theory to permit bootstrapping, or even exactly what counts as a bootstrapping case. Going back to Vogel's original bootstrapping example, I note that an agent who could gain justification through the method Vogel describes would have available a “no-lose investigation”: an investigation that can justify a proposition but has no possibility of undermining it. (...) The main suggestion of this article is that an epistemological theory should not permit no-lose investigations. I identify necessary and sufficient conditions for such investigations, then explore epistemological theories that rule them out. If we want to avoid both skepticism and no-lose investigations, we must eschew either Closure or epistemic externalism. (shrink)

The Self-Intimation thesis has it that whatever justificatory status a proposition has, i.e., whether or not we are justified in believing it, we are justified in believing that it has that status. The Infallibility thesis has it that whatever justificatory status we are justified in believing that a proposition has, the proposition in fact has that status. Jointly, Self-Intimation and Infallibility imply that the justificatory status of a proposition closely aligns with the justification we have about that justificatory status. Self-Intimation (...) has two noteworthy implications. First, assuming that we never have sufficient justification for a proposition and for its negation, we can derive Infallibility from Self-Intimation. Interestingly, there seems to be no equivalently simple way to derive Self-Intimation from Infallibility. This asymmetry provides reason for thinking that bottom-level justification rather than top-level justification drives the explanation for why the levels of justification align. Second, Self-Intimation suggests a counterintuitive treatment of information concerning what justificatory status a proposition has. It follows from Self-Intimation that we always have justification for the truth about whether a proposition is justified for us, and therefore, that higher-order evidence could change what we should believe on this matter only by misleading us. This permits forming beliefs about whether a proposition is justified for us without regard to higher-order evidence, and thus reveals a reason for thinking that top-level justification is evidentially inert. (shrink)

Suppose we learn that we have a poor track record in forming beliefs rationally, or that a brilliant colleague thinks that we believe P irrationally. Does such input require us to revise those beliefs whose rationality is in question? When we gain information suggesting that our beliefs are irrational, we are in one of two general cases. In the first case we made no error, and our beliefs are rational. In that case the input to the contrary is misleading. In (...) the second case we indeed believe irrationally, and our original evidence already requires us to fix our mistake. In that case the input to that effect is normatively superfluous. Thus, we know that information suggesting that our beliefs are irrational is either misleading or superfluous. This, I submit, renders the input incapable of justifying belief revision, despite our not knowing which of the two kinds it is. (shrink)

Does rationality require logical omniscience? Our best formal theories of rationality imply that it does, but our ordinary evaluations of rationality seem to suggest otherwise. This paper aims to resolve the tension by arguing that our ordinary evaluations of rationality are not only consistent with the thesis that rationality requires logical omniscience, but also provide a compelling rationale for accepting this thesis in the first place. This paper also defends an account of apriori justification for logical beliefs that is designed (...) to explain the rational requirement of logical omniscience. On this account, apriori justification for beliefs about logic has its source in logical facts, rather than psychological facts about experience, reasoning, or understanding. This account has important consequences for the epistemic role of experience in the logical domain. In a slogan, the epistemic role of experience in the apriori domain is not a justifying role, but rather an enabling and disabling role. (shrink)

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)

Should you always be certain about what you should believe? In other words, does rationality demand higher-order certainty? First answer: Yes! Higher-order uncertainty can’t be rational, since it breeds at least a mild form of epistemic akrasia. Second answer: No! Higher-order certainty can’t be rational, since it licenses a dogmatic kind of insensitivity to higher-order evidence. Which answer wins out? The first, I argue. Once we get clearer about what higher-order certainty is, a view emerges on which higher-order certainty does (...) not, in fact, license any kind of insensitivity to higher-order evidence. The view as I will describe it has plenty of intuitive appeal. But it is not without substantive commitments: it implies a strong form of internalism about epistemic rationality, and forces us to reconsider standard ways of thinking about the nature of evidential support. Yet, the view put forth promises a simple and elegant solution to a surprisingly difficult problem in our understanding of rational belief. (shrink)

It has been claimed that, in response to certain kinds of evidence, agents ought to adopt imprecise credences: doxastic states that are represented by sets of credence functions rather than single ones. In this paper I argue that, given some plausible constraints on accuracy measures, accuracy-centered epistemologists must reject the requirement to adopt imprecise credences. I then show that even the claim that imprecise credences are permitted is problematic for accuracy-centered epistemology. It follows that if imprecise credal states are permitted (...) or required in the cases that their defenders appeal to, then the requirements of rationality can outstrip what would be warranted by an interest in accuracy. (shrink)

A defense of imprecise credences (and other imprecise doxastic attitudes).

Greaves and Wallace argue that conditionalization maximizes expected accuracy. In this paper I show that their result only applies to a restricted range of cases. I then show that the update procedure that maximizes expected accuracy in general is one in which, upon learning P, we conditionalize, not on P, but on the proposition that we learned P. After proving this result, I provide further generalizations and show that much of the accuracy-first epistemology program is committed to KK-like iteration principles (...) and to the existence of a class of propositions that rational agents will be certain of if and only if they are true. (shrink)

This paper is about the connection between rationality and accuracy. I show that one natural picture about how rationality and accuracy are connected emerges if we assume that rational agents are rationally omniscient. I then develop an alternative picture that allows us to relax this assumption, in order to accommodate certain views about higher order evidence.

The aim of this paper is to describe a problem for calibrationism: a view about higher order evidence according to which one's credences should be calibrated to one's expected degree of reliability. Calibrationism is attractive, in part, because it explains our intuitive judgments, and provides a strong motivation for certain theories about higher order evidence and peer disagreement. However, I will argue that calibrationism faces a dilemma: There are two versions of the view one might adopt. The first version, I (...) argue, has the implausible consequence that, in a wide range of cases, calibrationism is the only constraint on rational belief. The second version, in addition to having some puzzling consequences, is unmotivated. At the end of the paper I sketch a possible solution. (shrink)

The aim of this paper is to apply the accuracy based approach to epistemology to the case of higher order evidence: evidence that bears on the rationality of one's beliefs. I proceed in two stages. First, I show that the accuracy based framework that is standardly used to motivate rational requirements supports steadfastness—a position according to which higher order evidence should have no impact on one's doxastic attitudes towards first order propositions. The argument for this will require a generalization of (...) an important result by Greaves and Wallace for the claim that conditionalization maximizes expected accuracy. The generalization I provide will, among other things, allow us to apply the result to cases of self-locating evidence. In the second stage, I develop an alternative framework. Very roughly, what distinguishes the traditional approach from the alternative one is that, on the traditional picture, we're interested in evaluating the expected accuracy of conforming to an update procedure. On the alternative picture that I develop, instead of considering how good an update procedure is as a plan to conform to, we consider how good it is as a plan to make. I show how, given the use of strictly proper scoring rules, the alternative picture vindicates calibrationism: a view according to which higher order evidence should have a significant impact on our beliefs. I conclude with some thoughts about why higher order evidence poses a serious challenge for standard ways of thinking about rationality. (shrink)

Epistemologists have recently noted a tension between (i) denying access internalism, and (ii) maintaining that rational agents cannot be epistemically akratic, believing claims akin to ‘p, but I shouldn’t believe p’. I bring out the tension, and develop a new way to resolve it. The basic strategy is to say that access internalism is false, but that counterexamples to it are ‘elusive’ in a way that prevents rational agents from suspecting that they themselves are counterexamples to the internalist principles. I (...) argue that this allows us to do justice to the motivations behind both (i) and (ii). And I explain in some detail what a view of evidence that implements this strategy, and makes it independently plausible, might look like. (shrink)

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. (shrink)

There is a widespread view that in order to be rational we must mostly know what we believe. In the probabilistic tradition this is defended by arguments that a person who failed to have this knowledge would be vulnerable to sure loss, or probabilistically incoherent. I argue that even gross failure to know one's own beliefs need not expose one to sure loss, and does not if we follow a generalization of the standard bridge principle between first-order and second-order beliefs. (...) This makes it possible for a subject to use probabilistic decision theory to manage in a rational way cases of potential failure of this self-knowledge, as we find in implicit bias. Through such cases I argue that it is possible for uncertainty about what our beliefs are to be not only rationally permissible but advantageous. (shrink)

Why should a Bayesian bother performing an experiment, one the result of which might well upset his own favored credence function? The Ramsey-Good theorem provides a decision theoretic answer. Provided you base your decision on expected utility, and the the experiment is cost-free, performing the experiment and then choosing has at least as much expected utility as choosing without further ado. Furthermore, doing the experiment is strictly preferable just in case at least one possible outcome of the experiment could alter (...) your choice of options. That is, you should pursue the information just in case it could make a difference to what you do. The problem remains, however, why one should do an experiment when nothing of much practical consequence hangs in the balance. One possibility here is to invoke the pure cognitive utility of states. It is shown that one constraint on cognitive value (what I call cogency) guarantees the value of learning: from a cognitive point of view you are justified in performing an experiment if the outcome of the experiment could make a different to what you think. A bonus of the basic framework is that it provides a new decision theoretic argument for the rationality of conditionalization. (shrink)

Timothy Williamson claims that margin for error principles govern all cases of inexact knowledge. I show that this claim is unfounded: there are cases of inexact knowledge where Williamson’s argument for margin for error principles does not go through. The problematic cases are those where the value of the relevant parameter is fixed across close cases. I explore and reject two responses to my objection, before concluding that Williamson’s account of inexact knowledge is not compelling.

This paper is about the standard Reflection Principle :235–256, 1984) and the Group Reflection Principle :478–502, 2007; Bovens and Rabinowicz in Episteme 8:281–300, 2011; Titelbaum in Quitting certainties: a Bayesian framework modeling degrees of belief, OUP, Oxford, 2012; Hedden in Mind 124:449–491, 2015). I argue that these principles are incomplete as they stand. The key point is that deference is an intensional relation, and so whether you are rationally required to defer to a person at a time can depend on (...) how that person and that time are designated. In this paper I suggest a way of completing the Reflection Principle and Group Reflection Principle, and I argue that so completed these principles are plausible. In particular, they do not fall foul of the Sleeping Beauty case :143–147, 2000), the Cable Guy Paradox :112–119, 2005), Arntzenius’ prisoner cases :356–370, 2003), or the Puzzle of the Hats :281–300, 2011). (shrink)

In this paper, I present a puzzle about epistemic rationality. It seems plausible that it should be rational to believe a proposition if you have sufficient evidential support for it. It seems plausible that it rationality requires you to conform to the categorical requirements of rationality. It also seems plausible that our first-order attitudes ought to mesh with our higher-order attitudes. It seems unfortunate that we cannot accept all three claims about rationality. I will present three ways of trying to (...) resolve this tension and argue that the best way to do this is to reject the idea that strong evidential support is the stuff rationality is made of. In the course of doing this, I shall argue that there is a special class of propositions about the requirements of rationality that we cannot make rational mistakes about and explain how this can be. (shrink)

A familiar complaint about conciliatory approaches to disagreement is that they are self-defeating or incoherent because they ‘call for their own rejection’. This complaint seems to be influential but it isn’t clear whether conciliatory views call for their own rejection or what, if anything, this tells us about the coherence of such views. We shall look at two ways of developing this self-defeat objection and we shall see that conciliatory views emerge unscathed. A simple version of the self-defeat objection leaves (...) conciliatory views untouched. A subtle version of the objection contains a subtle but overlooked flaw. If the conciliatory view is right, it might be right to be dogmatically conciliatory (i.e., to continue to be conciliatory however objectionable this might seem to ourselves and to others). (shrink)

Chance both guides our credences and is an objective feature of the world. How and why we should conform our credences to chance depends on the underlying metaphysical account of what chance is. I use considerations of accuracy (how close your credences come to truth-values) to propose a new way of deferring to chance. The principle I endorse, called the Trust Principle, requires chance to be a good guide to the world, permits modest chances, tells us how to listen to (...) chance even when the chances are modest, and entails but is not entailed by the New Principle. As I show, a rational agent will obey this principle if and only if she expects chance to be at least as accurate as she is on every good way of measuring accuracy. Much of the discussion, and the technical results, extend beyond chance to deference to any kind of expert. Indeed, you will trust someone about a particular question just in case you expect that person to be more accurate than you are about that question. (shrink)

Robert Aumann presents his Agreement Theorem as the key conditional: “if two people have the same priors and their posteriors for an event A are common knowledge, then these posteriors are equal” (Aumann, 1976, p. 1236). This paper focuses on four assumptions which are used in Aumann’s proof but are not explicit in the key conditional: (1) that agents commonly know, of some prior μ, that it is the common prior; (2) that agents commonly know that each of them updates (...) on the prior by conditionalization; (3) that agents commonly know that if an agent knows a proposition, she knows that she knows that proposition (the “K K” principle); (4) that agents commonly know that they each update only on true propositions. It is shown that natural weakenings of any one of these strong assumptions can lead to countermodels to Aumann’s key conditional. Examples are given in which agents who have a common prior and commonly know what probability they each assign to a proposition nevertheless assign that proposition unequal probabilities. To alter Aumann’s famous slogan: people can “agree to disagree”, even if they share a common prior. The epistemological significance of these examples is presented in terms of their role in a defense of the Uniqueness Thesis: If an agent whose total evidence is E is fully rational in taking doxastic attitude D to P, then necessarily, any subject with total evidence E who takes a different attitude to P is less than fully rational. (shrink)

Numerous authors have defended the rough idea that it is irrational to fail to conform to one’s judgments about what it would be rational to do, or what doxastic states it would be rational to be in. This chapter examines rational reflection principles as an attempt to implement this idea in contexts of uncertainty about what credence distributions are rational. After outlining some problems with Old Rational Reflection, the chapter discusses what seems like a well-motivated fix, New Rational Reflection. It (...) is argued that an intuitive way of trying to motivate the principle fails, and that it faces counterexamples. To say the least, the principle imposes substantial and controversial constraints on the kinds of epistemic situations it is possible to be in. A more general problem is that rational reflection principles seem doomed to take seriously certain kinds of uncertainty about what is rational, but not others. (shrink)

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

I formulate a resilient paradox about epistemic rationality, discuss and reject various solutions, and sketch a way out. The paradox exemplifies a tension between a wide range of views of epistemic justification, on the one hand, and enkratic requirements on rationality, on the other. According to the enkratic requirements, certain mismatched doxastic states are irrational, such as believing p, while believing that it is irrational for one to believe p. I focus on an evidentialist view of justification on which a (...) doxastic state regarding a proposition p is epistemically rational or justified just in case it tracks the degree to which one’s evidence supports p. If it is possible to have certain kinds of misleading evidence, then evidentialism and the enkratic requirements come into conflict. Yet, both have been defended as platitudinous. After discussing and rejecting three solutions, I sketch an account that rejects the enkratic requirements, while nevertheless explaining our sense that epistemic akrasia is a distinct kind of epistemic failure. Central to the account is distinguishing between two evaluative perspectives, one having to do with the relevant kind of success, the other having to do with manifesting good dispositions. The problem with akratic subjects, I argue, is that they manifest dispositions to fail to correctly respond to a special class of conclusive and conspicuous reasons. (shrink)

What sort of doxastic response is rational to learning that one disagrees with an epistemic peer who has evaluated the same evidence? I argue that even weak general recommendations run the risk of being incompatible with a pair of real epistemic phenomena, what I call evidential attenuation and evidential amplification. I focus on a popular and intuitive view of disagreement, the equal weight view. I take it to state that in cases of peer disagreement, a subject ought to end up (...) equally confident that her own opinion is correct as that the opinion of her peer is. I say why we should regard the equal weight view as a synchronic constraint on (prior) credence functions. I then spell out a trilemma for the view: it violates what are intuitively correct updates (also leading to violations of conditionalisation), it poses implausible restrictions on prior credence functions, or it is non-substantive. The sorts of reasons why the equal weight view fails apply to other views as well: there is no blanket answer to the question of how a subject should adjust her opinions in cases of peer disagreement. (shrink)

Philosophy and Phenomenological Research, EarlyView.

Epistemologists often assume that rationality bears an important connection to the truth. In this paper I examine the implications of this commitment for permissivism: if rationality is a guide to the truth, can it also allow some leeway in how we should respond to our evidence? I first discuss a particular strategy for connecting permissive rationality and the truth, developed in a recent paper by Miriam Schoenfield. I argue that this limited truth-connection is unsatisfying, and the version of permissivism that (...) supports it faces serious challenges; so, for mainstream permissivism, the truth problem is still unsolved. I then discuss a strategy available to impermissivists, according to which rationality bears a quite strong connection to truth. I argue that this second strategy is successful. (shrink)