Unlike with randomized controlled trials (RCTs) in clinical research, little has been said about the ethical principles that should regulate the use of RCTs in experimental development economics. One well-known principle in clinical research ethics is the principle of clinical equipoise. Some recent commentators suggest that an analogue of clinical equipoise should play a role in experimental development economics. In this article, I first highlight some difficulties with importing the concept to experimental development economics. I then argue that MacKay’s (2018, 2020) notion of policy equipoise avoids these difficulties and has a role to play in experimental development economics.

What gives the benefit principle its moral appeal as an idea of tax justice? And what can count as a benefit for that purpose? My claim is that we can trace the moral force of various versions of the principle to five ideas: individual justification, causal feedback, reciprocity, opposable valuation and non-objectionable baseline. I develop those ideas into an account of the moral permissibility of benefit-based taxation, and explain how that account addresses problems about the quantification and valuation of benefits and the relationship between benefit and the justice of the background distribution.

There is no consensus on how to infer welfare from inconsistent choices. We argue that theorists must be explicit about the values they endorse to characterize individual welfare. After formalizing a set of values and their relationship with context-independent choices, we review the literature and discuss the advantages and drawbacks of each approach. We demonstrate that defining welfare a priori may violate normative individualism, arguably the most desirable value to maintain. To uphold this value while addressing individuals’ errors, we propose a weaker version of consumer sovereignty, which we label ‘consumer autonomy’.

Common sense morality follows – in many cases – the prescriptions of threshold deontology. Governments, for example, are expected to follow their own rules, but in the face of an extreme price increase, public opinion has often supported changing the rules ex post to increase tax revenues. Such moral license in extreme situations is puzzling from a philosophical and an economic point of view. We present a simple contractualist solution to this puzzle using a game-theoretic model. We argue that allowing for deviations from the social contract in extreme circumstances is a necessary condition for the stability of any social contract.

Political Equality is the view that, in political matters, everyone should have an equal say. Political Sufficiency is the view that, in political matters, everyone should have enough of a say. Whereas Political Equality is concerned with relativities, Political Sufficiency is a matter of absolutes. It is natural to assume that, to justify ‘one person, one vote’, we must appeal to Political Equality. We argue that this is not the case. If Political Equality justifies ‘one person, one vote’, so does Political Sufficiency. Moreover, there is reason to prefer Political Sufficiency to Political Equality.

‘Positional goods’, a term coined by Fred Hirsch, is an important concept in economics, social sciences and philosophy; however, it is used in different ways. This paper recovers Hirsch’s concept of positional goods as scarce goods that are fixed or near-fixed in supply and argues for the usefulness of this concept. Hirsch’s concept may have explanatory power beyond the concept used by most economists – that of Robert Frank. Moreover, Hirsch’s concept is more explanatorily basic and useful than the concept used by most philosophers – that of Brighouse and Swift.

Cultural evolutionary models of bargaining can elucidate issues related to fairness and justice, and especially how fair and unfair conventions and norms might arise in human societies. One line of this research shows how the presence of social categories in such models creates inequitable equilibria that are not possible in models without social categories. This is taken to help explain why in human groups with social categories, inequity is the rule rather than the exception. But in previous models, it is typically assumed that these categories are rigid – in the sense that they cannot be altered, and easily observable – in the sense that all agents can identify each others’ category membership. In reality, social categories are not always so tidy. We introduce evolutionary models where the tags connected with social categories can be flexible, variable, or difficult to observe, i.e. where these tags can carry different amounts of information about group membership. We show how alterations to these tags can undermine the stability of unfair conventions. We argue that these results can inform projects intended to ameliorate inequity, especially projects that seek to alter the properties of tags by promoting experimentation, imitation, and play with identity markers.

This paper proposes a conceptual model of decision-making tying specific preferences to broader individual goals. Specifically, we consider terminal goals, representing fundamental objectives, and instrumental goals, serving as complexity-reducing intermediate steps toward achieving terminal goals and determining eventual preferences. Notably, the hierarchical goal structure allows for contextual misalignments between different instrumental goals, which may lead to suboptimal decisions – as evaluated from an outside perspective. Thus, applied to the discussion about nudging and paternalism, the model provides a methodological justification for paternalistic interventions as it is compatible with arguments in favour of interventions aimed to correct such choices.

Ambiguity, in the decision-theoretic sense, means that agents are unable to identify unique probabilities for some events that they care about. Ambiguity characterizes many real-life situations, but many important questions surrounding it are still open. Descriptively, we know that people typically perceive and are sensitive to ambiguity in certain kinds of situations. Intuitively, this is well justified. Normatively, however, many think that ambiguous beliefs and ambiguity sensitivity are irrational. This raises questions such as: Why are people sensitive to ambiguity? Does it lead to inferior decisions, in particular given people’s usual decision environments? An interesting clue is that there are many examples of social contexts in which ambiguity benefits everyone involved. Hence, we investigate the possibility that ambiguity sensitivity is ‘ecologically rational’ or adaptive in a multi-agent, strategic setting. We explore the viability of ambiguity sensitive behaviour using evolutionary simulations. Our results indicate that ambiguity sensitivity can be adaptive in strategic contexts, and is especially beneficial when agents have to coordinate.

This article presents a critique of Sergei Sazonov’s entrepreneurial theory of ownership. The article first reconstructs Sazonov’s response to the private duty imposition objection. It then demonstrates that Sazonov’s theory cannot overcome this objection because it is based on an ambiguity in the meaning of the word ‘use’. The entrepreneurial theory of ownership understands ‘use’ in a rather narrow and contradictory sense, which differs from the meaning in which this concept appears in objections to theories of original appropriation.

Responding to Konstantin Morozov’s article, which criticizes the Entrepreneurial Theory of Ownership, I point out that the reality of the right to unconsciously interact with objects, on which he heavily relies, is dubious.