Alejandro Pérez Carballo

Choices confront us with questions. How we act depends on our answers to those questions. So the way our beliefs guide our choices is not just a function of their informational content, but also depends systematically on the questions those beliefs address. This paper gives a precise account of the interplay between choices, questions and beliefs, and harnesses this account to obtain a principled approach to the problem of deduction. The result is a novel theory of belief-guided action that explains and predicts the decisions of agents who, like ourselves, fail to be logically omniscient: that is, of agents whose beliefs may not be deductively closed, or even consistent. (Winner of the 2021 Isaac Levi Prize.)

It is shown that two simple principles N and P concerning probabilities of conditionals can be combined with the standard ratio analysis of conditional probability only at the expense of complete triviality: no measure that satisfies all three can assign any proposition a non-trivial probability (probability greater than 0 and less than 1). The proof of this is trivial. Moreover, N and P are shown to follow from the Ramsey Test, Import–Export, Reflexivity and a weak principle of suppositional consistency (entailed by the ratio analysis), as well as from considerably weaker plausible properties. Together the results constitute a triviality result with a very strong conclusion from very weak premises, with a trivial proof. It sharpens the question: which principle is to blame?

Doing harm and allowing harm are not mutually exclusive. In fact, in most instances in which one does harm, one also thereby allows harm. I argue that, on its own, doing harm (without allowing it) carries little or no moral weight—surprisingly, less moral weight than merely allowing harm. On the other hand, doing harm while allowing it is significantly harder to justify than merely allowing it. I argue that ordinary harm-doing is especially hard to justify because it involves a convergence of doing and allowing harm. I show that this higher threshold for justification is not simply the result of an additive effect; rather, there is a moral synergy between doing harm and allowing the same harm to the same victim. I conclude by offering two possible explanations for the synergy, helping us to better clarify and recast the Doctrine of Doing and Allowing, as well as to determine its justification.

Fodor argued that learning a concept by hypothesis testing would involve an impossible circularity. I show that Fodor's argument implicitly relies on the assumption that actually φ-ing entails an ability to φ. But this assumption is false in cases of φ-ing by luck, and just such luck is involved in testing hypotheses with the kinds of generative random sampling methods that many cognitive scientists take our minds to use. Concepts thus can be learned by hypothesis testing without circularity, and it is plausible that this is how humans in fact acquire at least some of their concepts.

Accuracy-first accounts of rational learning attempt to vindicate the intuitive idea that, while rationally-formed belief need not be true, it is nevertheless likely to be true. To this end, they attempt to show that the Bayesian's rational learning norms are a consequence of the rational pursuit of accuracy. Existing accounts fall short of this goal, for they presuppose evidential norms which are not and cannot be vindicated in terms of the single-minded pursuit of accuracy. I propose an alternative account, according to which learning experiences rationalize changes in the way you value accuracy, which in turn rationalize changes in belief. I show that this account is capable of vindicating the Bayesian's rational learning norms in terms of the single-minded pursuit of accuracy, so long as accuracy is rationally valued.

This paper proposes a new account of bounded or minimal doxastic rationality (in the sense of Cherniak 1986), based on the notion that beliefs are answers to questions (à la Yalcin 2018). The core idea is that minimally rational beliefs are linked through thematic connections, rather than entailment relations. Consequently, such beliefs are not deductively closed, but they are closed under parthood (where a part is an entailment that answers a smaller question). And instead of avoiding all inconsistency, minimally rational believers only avoid blatant inconsistencies (where some beliefs are blatantly inconsistent when they contradict one another on a particular question). Rather than cohering into a single overall world view, beliefs are more loosely connected in what is best described as a web of questions. This view of minimally rational belief naturally gives rise to an account of deductive inquiry on which deductive reasoning is a matter of posing new questions.