How Norms (Might) Guide Belief

Abstract

Belief normativism is roughly the view that judgments about beliefs are normative judgments. Kathrin Glüer and Åsa Wikforss (G&W) suggest that there are two ways one could defend this view: by appeal to what might be called ‘truth-norms’, or by appeal to what might be called ‘norms of rationality’ or ‘epistemic norms’. According to G&W, whichever way the normativist takes, she ends up being unable to account for the idea that the norms in question would guide belief formation. Plausibly, if belief normativism were true, the relevant norms would have to offer such guidance. I argue that G&W’s case against belief normativism is not successful. In section 1, I defend the idea that truth-norms can guide belief formation indirectly via epistemic norms. In section 2, I outline an account of how the epistemic norms might guide belief. Interestingly, this account may involve a commitment to a certain kind of expressivist view concerning judgments about epistemic norms.     

Accuracy,Verisimilitude, and Scoring Rules

Suppose that beliefs come in degrees. How should we then measure the accuracy of these degrees of belief? Scoring rules are usually thought to be the mathematical tool appropriate for this job. But there are many scoring rules, which lead to different ordinal accuracy rankings. Recently, Fallis and Lewis [2016] have given an argument that, if sound, rules out many popular scoring rules, including the Brier score, as genuine measures of accuracy. I respond to this argument, in part by noting that the argument fails to account for verisimilitude—that certain false hypotheses might be closer to the truth than other false hypotheses are. Oddie [forthcoming], however, has argued that no member of a very wide class of scoring rules (the so-called proper scores) can appropriately handle verisimilitude. I explain how to respond to Oddie's argument, and I recommend a class of weighted scoring rules that, I argue, genuinely measure accuracy while escaping the arguments of Fallis and Lewis as well as Oddie.     

New Horizons for a Theory of Epistemic Modals

Recent debate over the semantics and pragmatics of epistemic modals has focused on intuitions about cross-contextual truth-value assessments. In this paper, we advocate a different approach to evaluating theories of epistemic modals. Our strategy focuses on judgments of the incompatibility of two different epistemic possibility claims, or two different truth value assessments of a single epistemic possibility claim. We subject the predictions of existing theories to empirical scrutiny, and argue that existing contextualist and relativist theories are unable to account for the full pattern of observed judgments. As a way of illustrating the theoretical upshot of these results, we conclude by developing a novel theory of epistemic modals that is able to predict the results.     

Chisholm's Epistemic Principles

Abstract: An exposition and discussion of Chisholm's “epistemic principles.” These are compared with relevant views of Wilfrid Sellars and Richard Foley. A further comparison, with the approach favored by Descartes, is argued to throw light on the status of such principles.     

Peer Disagreement and Two Principles of Rational Belief

This paper presents a new solution to the problem of peer disagreement that distinguishes two principles of rational belief, here called probability and autonomy. When we discover that we disagree with peers, there is one sense in which we rationally ought to suspend belief, and another in which we rationally ought to retain our original belief. In the first sense, we aim to believe what is most probably true according to our total evidence, including testimony from peers and authorities. In the second, we aim to base our beliefs only on objective evidence and argumentation, even if that lowers the probability of their being true. The first principle of rational belief tends to serve the short-term epistemic interests of individuals, while the second tends to serve the long-term epistemic interests of both individuals and groups. The best way to reconcile these principles in cases of peer disagreement is to associate them with two corresponding species of belief, here called perception and opinion.     

Iterated Belief Change and the Recovery Axiom

The axiom of recovery, while capturing a central intuition regarding belief change, has been the source of much controversy. We argue briefly against putative counterexamples to the axiom—while agreeing that some of their insight deserves to be preserved—and present additional recovery-like axioms in a framework that uses epistemic states, which encode preferences, as the object of revisions. This makes iterated revision possible and renders explicit the connection between iterated belief change and the axiom of recovery. We provide a representation theorem that connects the semantic conditions we impose on iterated revision and our additional syntactical properties. We show interesting similarities between our framework and that of Darwiche–Pearl (Artificial Intelligence 89:1–29 1997). In particular, we show that intuitions underlying the controversial (C2) postulate are captured by the recovery axiom and our recovery-like postulates (the latter can be seen as weakenings of (C2)). We present postulates for contraction, in the same spirit as the Darwiche–Pearl postulates for revision, and provide a theorem that connects our syntactic postulates with a set of semantic conditions. Lastly, we show a connection between the contraction postulates and a generalisation of the recovery axiom. Portions of this paper were originally presented at ECAI 2002.