•  4451
    Rational Polarization
    Philosophical Review 132 (3): 355-458. 2023.
    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 …Read more
  •  2609
    Evidence: A Guide for the Uncertain
    Philosophy and Phenomenological Research 100 (3): 586-632. 2019.
    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…Read more
  •  2156
    Good Guesses
    Philosophy and Phenomenological Research 105 (3): 581-618. 2023.
    This paper is about guessing: how people respond to a question when they aren’t certain of the answer. Guesses show surprising and systematic patterns that the most obvious theories don’t explain. We argue that these patterns reveal that people aim to optimize a tradeoff between accuracy and informativity when forming their guess. After spelling out our theory, we use it to argue that guessing plays a central role in our cognitive lives. In particular, our account of guessing yields new theories…Read more
  •  1959
    Being Rational and Being Wrong
    Philosophers' Imprint 23 (1). 2023.
    Do people tend to be overconfident? Many think so. They’ve run studies on whether people are calibrated: whether their average confidence in their opinions matches the proportion of those opinions that are true. Under certain conditions, people are systematically ‘over-calibrated’—for example, of the opinions they’re 80% confident in, only 60% are true. From this empirical over-calibration, it’s inferred that people are irrationally overconfident. My question: When and why is this inference warr…Read more
  •  1650
    Lockeans Maximize Expected Accuracy
    Mind 128 (509): 175-211. 2019.
    The Lockean Thesis says that you must believe p iff you’re sufficiently confident of it. On some versions, the 'must' asserts a metaphysical connection; on others, it asserts a normative one. On some versions, 'sufficiently confident' refers to a fixed threshold of credence; on others, it varies with proposition and context. Claim: the Lockean Thesis follows from epistemic utility theory—the view that rational requirements are constrained by the norm to promote accuracy. Different versions of th…Read more
  •  1422
    Higher-Order Evidence
    In Maria Lasonen-Aarnio & Clayton Littlejohn (eds.), The Routledge Handbook for the Philosophy of Evidence, Routledge. pp. 176-194. 2024.
    On at least one of its uses, ‘higher-order evidence’ refers to evidence about what opinions are rationalized by your evidence. This chapter surveys the foundational epistemological questions raised by such evidence, the methods that have proven useful for answering them, and the potential consequences and applications of such answers
  •  1293
    Abominable KK Failures
    Mind 128 (512): 1227-1259. 2019.
    KK is the thesis that if you can know p, you can know that you can know p. Though it’s unpopular, a flurry of considerations has recently emerged in its favour. Here we add fuel to the fire: standard resources allow us to show that any failure of KK will lead to the knowability and assertability of abominable indicative conditionals of the form ‘If I don’t know it, p’. Such conditionals are manifestly not assertable—a fact that KK defenders can easily explain. I survey a variety of KK-denying re…Read more
  •  1127
    Higher-order uncertainty
    In Mattias Skipper & Asbjørn Steglich-Petersen (eds.), Higher-Order Evidence: New Essays, Oxford University Press. 2019.
    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 foundatio…Read more
  •  978
    (Almost) all evidence is higher-order evidence
    Analysis 82 (3): 417-425. 2022.
    Higher-order evidence is evidence about what is rational to think in light of your evidence. Many have argued that it is special – falling into its own evidential category, or leading to deviations from standard rational norms. But it is not. Given standard assumptions, almost all evidence is higher-order evidence.
  •  961
    Assertion is weak
    Philosophers' Imprint 22 (n/a). 2022.
    Recent work has argued that belief is weak: the level of rational credence required for belief is relatively low. That literature has contrasted belief with assertion, arguing that the latter requires an epistemic state much stronger than (weak) belief---perhaps knowledge or even certainty. We argue that this is wrong: assertion is just as weak as belief. We first present a variety of new arguments for this, and then show that the standard arguments for stronger norms are not convincing. Finally…Read more
  •  869
    Splitting the (In)Difference: Why Fine-Tuning Supports Design
    Thought: A Journal of Philosophy 11 (1): 14-23. 2022.
    Given the laws of our universe, the initial conditions and cosmological constants had to be "fine-tuned" to result in life. Is this evidence for design? We argue that we should be uncertain whether an ideal agent would take it to be so—but that given such uncertainty, we should react to fine-tuning by boosting our confidence in design. The degree to which we should do so depends on our credences in controversial metaphysical issues.
  •  839
    Be modest: you're living on the edge
    Analysis 81 (4): 611-621. 2022.
    Many have claimed that whenever an investigation might provide evidence for a claim, it might also provide evidence against it. Similarly, many have claimed that your credence should never be on the edge of the range of credences that you think might be rational. Surprisingly, both of these principles imply that you cannot rationally be modest: you cannot be uncertain what the rational opinions are.
  •  751
    Deference Done Better
    Philosophical Perspectives 35 (1): 99-150. 2021.
    There are many things—call them ‘experts’—that you should defer to in forming your opinions. The trouble is, many experts are modest: they’re less than certain that they are worthy of deference. When this happens, the standard theories of deference break down: the most popular (“Reflection”-style) principles collapse to inconsistency, while their most popular (“New-Reflection”-style) variants allow you to defer to someone while regarding them as an anti-expert. We propose a middle way: deferring…Read more
  •  573
    The gambler’s fallacy is the tendency to expect random processes to switch more often than they actually do—for example, to think that after a string of tails, a heads is more likely. It’s often taken to be evidence for irrationality. It isn’t. Rather, it’s to be expected from a group of Bayesians who begin with causal uncertainty, and then observe unbiased data from an (in fact) statistically independent process. Although they converge toward the truth, they do so in an asymmetric way—ruling ou…Read more
  •  573
    Why Rational People Polarize
    The Phenomenal World. 2019.
    I argue that several of the psychological tendencies that drive polarization could arise from purely rational mechanisms, due to the fact that some types of evidence are predictably more ambiguous than others.
  •  511
    Epistemic Consequentialism (review)
    Philosophical Review 129 (3): 484-489. 2020.
  •  415
    Can the Knowledge Norm Co‐Opt the Opt Out?
    Thought: A Journal of Philosophy 3 (4): 273-282. 2014.
    The Knowledge Norm of Assertion claims that it is proper to assert that p only if one knows that p. Though supported by a wide range of evidence, it appears to generate incorrect verdicts when applied to utterances of “I don't know.” Instead of being an objection to KNA, I argue that this linguistic data shows that “I don't know” does not standardly function as a literal assertion about one's epistemic status; rather, it is an indirect speech act that has the primary illocutionary force of optin…Read more
  •  399
    The conjunction fallacy is the well-documented empirical finding that subjects sometimes rate a conjunction A&B as more probable than one of its conjuncts, A. Most explanations appeal in some way to the fact that B has a high probability. But Tentori et al. (2013) have recently challenged such approaches, reporting experiments which find that (1) when B is confirmed by relevant evidence despite having low probability, the fallacy is common, and (2) when B has a high probability but has not been …Read more
  •  73
    Correction to: Be modest: you’re living on the edge
    Analysis 82 (3): 473-473. 2022.
    In typesetting the final version of this paper, an error was introduced in the formal notation. Dots used for multiplication were replaced by ampersands. Although this does not affect the result, it could be confusing for readers. The publisher and editors apologise for the error. This error has been corrected.