In a recent article in this journal, Duijf claims to have proved that team reasoning can be viewed as a payoff transformation. His formalization mimics team reasoning but ignores its essential agency switch. The possibility of such a payoff transformation was never in doubt, does not imply that team reasoning can be viewed as a payoff transformation, and makes no sense in a game in which payoffs represent players’ utilities. A theorem is proved here that a simpler and more intuitive payoff transformation can mimic any theory that predicts what strategies players will choose in a well-defined game.

We present an abstract model of rationality that focuses on structural properties of attitudes. Rationality requires coherence between your attitudes, such as your beliefs, values and intentions. We define three ‘logical’ conditions on attitudes: consistency, completeness and closedness. They parallel the familiar logical conditions on beliefs, but contrast with standard rationality conditions such as preference transitivity. We establish a formal correspondence between our logical conditions and standard rationality conditions. Addressing John Broome’s programme ‘rationality through reasoning’, we formally characterize how you can (not) become more logical by reasoning. Our analysis connects rationality with logic, and enables logical talk about multi-attitude psychology.

This article refines a foundational tenet of rational choice theory known as the principle of description invariance. Attempts to apply this principle to human agents with imperfect knowledge have paid insufficient attention to two aspects: first, agents’ epistemic situations, i.e. whether and when they recognize alternative descriptions of an object to be equivalent; and second, the individuation of objects of description, i.e. whether and when objects count as the same or different. An important consequence is that many apparent ‘framing effects’ may not violate the principle of description invariance, and the subjects of these effects may not be irrational.

According to the Welfare Diffusion Objection, we should reject Prioritarianism because it implies the ‘desirability of welfare diffusion’: the claim that it can be better for there to be less total wellbeing spread thinly between a larger total number of people, rather than for there to be more total wellbeing, spread more generously between a smaller total number of people. I argue that while Prioritarianism does not directly imply the desirability of welfare diffusion, Prioritarians are nevertheless implicitly committed to certain principles for comparing different-number populations which, together with the Prioritarian same-person axiology, imply the desirability of welfare diffusion.

Normative welfare economics commonly assumes that individuals’ preferences can be reliably inferred from their choices and relies on preference satisfaction as the normative standard for welfare. In recent years, several authors have criticized welfare economists’ reliance on preference satisfaction as the normative standard for welfare and have advocated grounding normative welfare economics on opportunities rather than preferences. In this paper, I argue that although preference-based approaches to normative welfare economics face significant conceptual and practical challenges, opportunity-based approaches fail to provide a more reliable and informative foundation for normative welfare economics than preference-based approaches. I then identify and rebut various influential calls to ground normative welfare economics on opportunities rather than preferences to support my qualified defence of preference-based approaches.

Individuals often deem market transactions in sex, human organs and surrogacy, among others, repugnant. Repugnance norms can be explained by appealing to social-status concerns. We study an exchange economy in which agents abhor consumption dominance: one’s social status is compromised if one consumes less of every good than someone else does. Dominance may be forestalled by partitioning goods into submarkets and then invoking the repugnance norms that proscribe trade across these submarkets. Dominance may also be forestalled if individuals strategically ‘overconsume’ some goods, interpreted as emergent status goods. When equilibria are multiple, there is scope for welfare-enhancing policies that coordinate on status goods.

Behavioural techniques or ‘nudges’ can be used for various purposes. In this paper, we shift the focus from government nudges to nudges used by for-profit market agents. We argue that potential worries about nudges circumventing the deliberative capacities or diminishing the control of targeted agents are greater when it comes to market nudges, given that these (1) are not constrained by the principles that regulate government nudges (mildness, sensitivity to people’s interests and public justifiability) and (2) are often ‘stacked’ – they come in great numbers that overwhelm agents. In addition, we respond to possible objections and derive several policy suggestions.

The philosophical debate concerning political exchange has largely been confined to debating the desirability of vote trading; where individuals can sell their votes or buy votes from others. However, I show that the vote credit systems prevalent in public choice theory entirely avoid the common objections to political exchange that afflict vote trading proposals. Namely, vote credit systems avoid equality concerns and inalienability concerns. I offer an alternative critique to formal mechanisms that encourage political exchange by drawing on the role that impartiality and impartial moral judgements play in democratic and electoral institutions.

In this paper we explore the absentminded driver problem using two different scenarios. In the first scenario we assume that the driver is capable of reasoning about his degree of absentmindedness before he hits the highway. This leads to a Savage-style model where the states are mutually exclusive and the act-state independence is in place. In the second we employ centred possibilities, by modelling the states (i.e. the events about which the driver is uncertain) as the possible final destinations indexed by a time period. The optimal probability we find for continuing at an exit is different from almost all papers in the literature. In this scenario, act-state independence is still violated, but states are mutually exclusive and the driver arrives at his optimal choice probability via Bayesian updating. We show that our solution is the only one guaranteeing immunity from sure loss via a Dutch strategy, and that – despite initial appearances – it is time consistent. This raises important implications for the rationality of commitment in such scenarios.

In Preference, Value, Choice, and Welfare, I argued, among other things, that preferences in economics are and ought to be total subjective comparative evaluations, that the theory of rational choice is a reformulation of everyday folk-psychological explanations and predictions of behaviour, and that revealed preference theory is completely untenable. All three of these theses have been challenged in essays by Erik Angner (2018), Francesco Guala (2019) and Johanna Thoma (2021a, 2021b). This essay responds to these criticisms and defends these three theses.