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.

Variable-Value axiologies avoid Parfit’s Repugnant Conclusion while satisfying some weak instances of the Mere Addition principle. We apply calibration methods to two leading members of the family of Variable-Value views conditional upon: first, a very weak instance of Mere Addition and, second, some plausible empirical assumptions about the size and welfare of the intertemporal world population. We find that such facts calibrate these two Variable-Value views to be nearly totalist, and therefore imply conclusions that should seem repugnant to anyone who opposes Total Utilitarianism only due to the Repugnant Conclusion.

It has been argued that Prioritarianism violates Risky Non-Antiegalitarianism, a condition stating roughly that an alternative is socially better than another if it both makes everyone better off in expectation and leads to more equality. I show that Risky Non-Antiegalitarianism is in fact compatible with Prioritarianism as ordinarily defined, but that it violates some other conditions that may be attractive to prioritarians. While I argue that the latter conditions are not core principles of Prioritarianism, the choice between these conditions and Risky Non-Antiegalitarianism nonetheless constitutes an important intramural debate for prioritarians.

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.

The valence of a life – that is, whether it is good, bad or neutral – is an important consideration in population ethics. This paper examines various definitions of valence. The main focus is ‘temporal’ definitions, which define valence in terms of the ‘shape’ of a life’s value over time. The paper argues that temporal definitions are viable only with a restricted domain, and therefore are incompatible with certain substantive theories of well-being. It also briefly considers some popular non-temporal definitions, and raises some problems for these.

Many philosophical accounts of manipulation are blind to the extent to which actual people fall short of the rational ideal, while prominent accounts in political science are under-inclusive. We offer necessary and sufficient conditions – Suitable Reason and Testimonial Honesty – distinguishing manipulative from non-manipulative influence; develop a ‘hypothetical disclosure test’ to measure the degree of manipulation; and provide further criteria to assess and compare the morality of manipulation across cases. We discuss multiple examples drawn from politics and from public policy with particular attention to recent debates about the ethics and politics of nudge.

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.

Relational egalitarians argue that workplace hierarchy is wrong or unjust. However, even if workplace hierarchy is morally deficient in one respect, the efficiency of hierarchical cooperation might vindicate hierarchy. This paper assesses the extent to which relational egalitarians must make concessions to workplace hierarchy for the sake of efficiency. I argue that considerations of hierarchy provide egalitarians with reasons that make workplace hierarchy tolerable despite being unjustified, and, moreover, that under a predominantly hierarchical status quo, the practical import of egalitarian reasons is unlikely to be undercut. This can be the case even if social hierarchy sometimes constitutes social cooperation.

Endörfer has recently argued that proponents of the harm principle are wrong to exempt market harms as potential justifications for state interference. I argue that – contrary to suggestions in Endörfer’s article – John Stuart Mill did not exempt market harms from his harm principle. On Mill’s view, the state can (as a matter of principle) legitimately interfere with free markets to prevent market harms where they occur but, on the whole, it is better policy not to interfere. Mill’s general preference for free trade rests on utilitarian considerations and not on his harm principle, which does not exclude market harms.

As readers of this journal can attest to, although philosophers and economists are somewhat used to talking to and learning from each other, it tends to be the subset of philosophers working in decision theory, philosophy of science, and particular areas of ethics and political philosophy that contribute to our interdisciplinary field of research. The book that is the subject of this review symposium, Anna Mahtani’s The Objects of Credence (Oxford University Press, 2024), is a wonderful exemplar of what can be learned when a different branch of philosophy is brought to bear on central questions in this field. Both philosophers and economists talk about and work with credences, or degrees of belief, all the time. These are usually modelled as probabilities, which are in turn usually thought of as attaching to propositions. But it has long been argued by philosophers of language that propositions cannot be the objects of credence. Mahtani’s book is an investigation into all that begins to unravel once we accept this insight. The results have profound implications both for rational choice modelling and for welfare economics.

The Objects of Credence grew from a simple insight, which is that credence claims are opaque (or ‘hyperintensional’). This central idea can be illustrated using the following example:

1. (1) Tom has a high credence that George Orwell is a writer.

2. (2) Tom has a low credence that Eric Blair is a writer.

In Chapter 6 of Objects of Credence, Anna Mahtani argues that the opacity of credence raises difficulties for the Principal Principle and proposes a revised principle relating credence and chance that avoids it. In this comment on her book, I both defend Mahtani’s proposed principle against a charge of triviality and argue that the opacity of belief does not threaten the role of chance in guiding credence.