This thesis is an investigation into the nature of epistemic justification. It brings together themes from traditional, individual-centred epistemology, and collective, group-centred epistemology. The first half of the thesis is concerned with the question of whether rationality is epistemically permissive; that is, whether one body of evidence can rationalise more than one doxastic attitude. In chapter 1, I argue that permissive cases are best understood as epistemic standard conflicts. Doing so provides us with a novel understanding of the arbitrariness objection (...) against permissivism and enables us to reduce questions about epistemic permissibility to questions about the nature of incommensurability. In chapter 2, I show that the defended understanding of permissive cases generalises by defending it against an objection from self-fulfilling beliefs. In chapter 3, I demonstrate that we can use this view of epistemic rationality to generate so-called divergence arguments which show that the epistemic status of group-level attitudes and member-level attitudes can rationally diverge. In the second half of the thesis, I develop a novel evidentialist theory of epistemic justification, called Continuous Evidentialism. Continuous Evidentialism is inspired by some general methodological reflections (chapter 4), which suggest that we should opt for a theory of epistemic justification that analyses the epistemic status of group-level attitudes and member-level attitudes continuously. According to Continuous Evidentialism, to have a justified belief is to possess sufficient evidence and utilise that evidence in an epistemically responsible way when forming the belief. While I argue that we can reduce epistemic responsibility to higher-order evidentialist requirements. In chapter 5, I develop a theory of evidence, evidence possession and epistemic basing. Chapters 6 - 8, discuss various complications of the proposed theory, having to do with the alleged defeasibility of justification (chapter 6), epistemic responsibility (chapter 7), and the proposed reduction of epistemic responsibility (chapter 8). In chapter 9, I compare Continuous Evidentialism to various extant accounts. (shrink)

Many evidentialists are impermissivists. But there’s no in-principle reason for this. In this paper, I examine and motivate permissivist evidentialism. Not only are permissivism and evidentialism compatible but there are unique benefits that arise for this combination of views. In particular, permissivist evidentialism respects the importance of evidence while capturing its limitations and provides a plausible and attractive explanation of the relationship between the epistemic and non-epistemic. Permissivist evidentialism is thus an attractive option in logical space that hasn’t received enough (...) attention. (shrink)

Predictable polarization is everywhere: we can often predict how people’s opinions, including our own, will shift over time. Extant theories either neglect the fact that we can predict our own polarization, or explain it through irrational mechanisms. They needn’t. Empirical studies suggest that polarization is predictable when evidence is ambiguous, that is, when the rational response is not obvious. I show how Bayesians should model such ambiguity and then prove that—assuming rational updates are those which obey the value of evidence—ambiguity (...) is necessary and sufficient for the rationality of predictable polarization. The main theoretical result is that there can be a series of such updates, each of which is individually expected to make you more accurate, but which together will predictably polarize you. Polarization results from asymmetric increases in accuracy. This mechanism is not only theoretically possible, but empirically plausible. I argue that cognitive search—searching a cognitively accessible space for a particular item—often yields asymmetrically ambiguous evidence, I present an experiment supporting its polarizing effects, and I use simulations to show how it can explain two of the core causes of polarization: confirmation bias and the group polarization effect. (shrink)

This paper argues for a permissivism of personal rationality, a rationality concerning the epistemic evaluation of persons. I work from the perspective of virtue epistemology where the standards of evaluation are the intellectual character virtues. On this picture, an agent is personally rational in having a doxastic attitude when having it is the result of some exemplification of an intellectual virtue. Permissive cases arise when the emotional components of intellectual virtues conflict, making some potential conclusions both enabled and disabled for (...) the agent. The agent is left in a confusion needing resolution, but if each of these conflicting emotions are components of intellectual virtues, then she has multiple personally rational options. This grounds a potential case of a permissivism of personal rationality, but this should be interesting to epistemologists in general since opting for one of the sides of this conflict leads an agent to have different doxastic attitudes. (shrink)

One famous debate in contemporary epistemology considers whether there is always one unique, epistemically rational way to respond to a given body of evidence. Generally speaking, answering “yes” to this question makes one a proponent of the Uniqueness thesis, while those who answer “no” are called “permissivists”. Another influential recent debate concerns whether non-truth-related factors can be the basis of epistemic justification, knowledge, or rational belief. Traditional theories answer “no”, and are therefore considered “purists”. However, more recently many theorists have (...) argued to the contrary, claiming that impurist factors, such as practical stakes, can sometimes encroach or even override truth-related considerations. This paper bridges the two debates by presenting and defending what I call “Impurist Permissivism”. I support Impurist Permissivism by showing how it can resist Roger White’s famous Argument from Arbitrariness (2005). (shrink)

When a belief has been influenced, in part or whole, by factors that, by the believer's own lights, do not bear on the truth of the believed proposition, we can say that the belief has been, in a sense, arbitrarily formed. Can such beliefs ever be rational? It might seem obvious that they can't. After all, belief, supposedly, “aims at the truth.” But many epistemologists have come to think that certain kinds of arbitrary beliefs can, indeed, be rational. In this (...) paper, I want to do two things. First, I want to show that the claim that arbitrary beliefs can be rational is inconsistent with the conjunction of two other attractive claims: one saying that rationality requires a certain kind of epistemic immodesty, and one saying that rationality forbids certain kinds of self-ascriptions of epistemic luck. Second, I want to evaluate different ways one might respond to this inconsistent triad. I won't defend any response in particular, but I'll draw out some notable costs and benefits of each response, which may help shed light on the question of whether arbitrary beliefs can be rational. (shrink)

There is an intuitive difference in how we think about pluralism and attitudinal diversity in epistemological contexts versus political contexts. In an epistemological context, it seems problematically arbitrary to hold a particular belief on some issue, while also thinking it perfectly reasonable to hold a totally different belief on the same issue given the same evidence. By contrast, though, it doesn’t seem problematically arbitrary to have a particular set of political commitments, while at the same time thinking it perfectly reasonable (...) for someone in a similar position have a totally different set of political commitments. This chapter examines three explanatory theses that might be used to make sense of this difference: (1) that practical commitments are desire dependent in a way that beliefs are not; (2) that there are reasons to be resolute in practical commitments, but not in beliefs; and (3) that compromise in the face of practical political disagreement doesn’t mitigate controversy, whereas compromise in the face of disagreement about mere beliefs does mitigate controversy. (shrink)

Recent work has argued that there may be cases where no attitude – including withholding – is rationally permissible. In this paper, I consider two such epistemic dilemmas, John Turri’s Dilemma from Testimony and David Alexander’s Dilemma from Doubt. Turri presents a case where one’s only evidence rules out withholding (without warranting belief or disbelief). Alexander presents a case where higher order doubt means one must withhold judgment over whether withholding judgment is rational. In both cases, the authors conclude that (...) no doxastic attitude is warranted. In this paper, I argue against the possibility of these epistemic dilemmas. I argue that withholding cannot be irrational in either case. But meditating on the dilemmas gives us an important – and overlooked – insight into the nature of rational withholding. First, rational withholding is a function of evidence failing to sufficiently support belief or disbelief. As a result, withholding is not symmetrical to belief and disbelief. Second, there can be two distinct grounds for rational withholding. First, propositional withholding, which arises when our evidence does not support belief or disbelief in p. And second, doxastic withholding, which arises when we cannot determine whether our evidence supports belief or disbelief in p. Accepting two grounds of rational withholding licenses a kind of Weak Permissivism. But this Weak Permissivism should not be troubling to anyone. (shrink)

There is now a significant body of literature on consequentialist ethics that propose satisficing instead of maximizing accounts. Even though epistemology recently witnessed a widespread discussion of teleological and consequentialist theories, a satisficing account is surprisingly not developed yet. The aim of this paper is to do just that. The rough idea is that epistemic rules are justified if and only if they satisfice the epistemic good, i.e., reach some threshold of epistemic value (which varies with practical context), and believing (...) is justified if and only if it follows said rules.I argue that this alternative to the implicitly established way of thinking in maximizing terms has significant advantages. First, maximizing epistemic value can be unreasonably demanding; second, a satisficing theory can make finding reasonable rules for belief formation and sustenance much more accessible; and third, a satisficing approach is a better alternative to both general subjectivist and maximizing objectivist attempts to spell out epistemic blame. (shrink)