H. Orri Stefansson

Many philosophers think that we should use a lottery to decide who gets a good to which two persons have an equal claim but which only one person can get. Some philosophers think that we should save identified persons from harm even at the expense of saving a somewhat greater number of statistical persons from the same harm. I defend a principled way of justifying both judgements, namely, by appealing to the decreasing marginal moral value of survival chances. I identify four desiderata that, I contend, any such justification should satisfy, and explain how my account meets these desiderata, unlike some previous accounts.

Parfit (Theoria 82:110–127, 2016) responded to the Sequence Argument for the Repugnant Conclusion by introducing imprecise equality. However, Parfit’s notion of imprecise equality lacked structure. Hájek and Rabinowicz (2022) improved on Parfit’s proposal in this regard, by introducing a notion of degrees of incommensurability. Although Hájek and Rabinowicz’s proposal is a step forward, and may help solve many paradoxes, it can only avoid the Repugnant Conclusion at great cost. First, there is a sequential argument for the Repugnant Conclusion that uses weaker and intuitively more compelling assumptions than the Sequence Argument, and which Hájek and Rabinowicz’s proposal only undermines, in a principled way, by allowing for implausible weight to be put on the disvalue of inequality. Second, if Hájek and Rabinowicz do put such implausible weight on the disvalue of inequality, then they will have to accept that a population A is not worse than another same sized population B even though everyone in B is better off than anyone in A.

Bartha and DesRoches (Synthese 199(3–4):8701–8740, 2021) and Steel and Bartha (Risk Analysis 43(2):260–268, 2023) argue that we should understand the precautionary principle as the injunction to maximise lexical utilities. They show that the lexical utility model has important pragmatic advantages. Moreover, the model has the theoretical advantage of satisfying all axioms of expected utility theory except continuity. In this paper I raise a trilemma for any attempt at modelling the precautionary principle with lexical utilities: it permits choice cycles or leads to paralysis or implies that the smallest value difference that is possible in a context has extreme axiological implications.

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.

Recently, Martin Smith defended a view he called the “normic de minimis expected utility theory”. The basic idea is to integrate a ‘normic’ version of the de minimis principle into an expected utility-based decision theoretical framework. According to the de minimis principle some risks are so small (falling below a threshold) that they can be ignored. While this threshold standardly is defined in terms of some probability, the normic conception of de minimis defines this threshold in terms of abnormality. In this article, we present three independent arguments against the normic de minimis expected utility theory, focusing on its reliance on the de minimis principle.

Ocean-based salmon farming, as presently practiced, is thought to pose an existential threat to what we today think of as wild salmon. This raises ethical questions about, first, the value of wild salmon, and, second, the value of wild salmon of the particular type that exists today. This essay uses the debate around ocean-based salmon farming as a case study of ‘irreversible damage,’ a concept that figures heavily in environmental laws and regulations, in particular, in the so-called ‘precautionary principle.’ It is argued that although ocean-based salmon farming may, on the surface, seem to be a prime example of a threat of irreversible damage, a wish to avoid irreversible damage does not support banning such farming. In contrast, it is argued that concern for irreplaceable value might support a ban. The findings suggest that it often would be appropriate for environmentalists and conservationists to focus more on irreplaceable value and less on irreversible damage.

Considerations of dynamic inconsistency have figured prominently in debates over the rationality of preferences that violate the separability conditions characteristic of expected utility theory. These debates have mostly focused on risk- and ambiguity averse preferences, but analogous considerations apply to preferences for fairness. We revisit these debates in the context of a specific hypothesis regarding the violations of separability by such preferences, namely that they are potentially both explained and rationalised by attitudes to the chances of goods that motivate a preference for equality in the distribution of chances across people and possible events. Our main aim is to argue that, first, when these violations of static separability are motivated by such attitudes to chances, then they need not result in dynamically inconsistent behaviour. Second, and more generally, considerations of dynamic consistency do not, we argue, undermine the rationality of such attitudes towards the distribution of chances, despite the fact that such attitudes give rise to violations of the static separability assumptions of expected utility theory.

Parfit (Theoria 82:110–127, 2016) responded to the Sequence Argument for the Repugnant Conclusion by introducing imprecise equality. However, Parfit’s notion of imprecise equality lacked structure. Hájek and Rabinowicz (2022) improved on Parfit’s proposal in this regard, by introducing a notion of degrees of incommensurability. Although Hájek and Rabinowicz’s proposal is a step forward, and may help solve many paradoxes, it can only avoid the Repugnant Conclusion at great cost. First, there is a sequential argument for the Repugnant Conclusion that uses weaker and intuitively more compelling assumptions than the Sequence Argument, and which Hájek and Rabinowicz’s proposal only undermines, in a principled way, by allowing for implausible weight to be put on the disvalue of inequality. Second, if Hájek and Rabinowicz do put such implausible weight on the disvalue of inequality, then they will have to accept that a population A is not worse than another same sized population B even though everyone in B is better off than anyone in A.

Recently, Martin Smith defended a view he called the “normic de minimis expected utility theory”. The basic idea is to integrate a ‘normic’ version of the de minimis principle into an expected utility-based decision theoretical framework. According to the de minimis principle some risks are so small (falling below a threshold) that they can be ignored. While this threshold standardly is defined in terms of some probability, the normic conception of de minimis defines this threshold in terms of abnormality. In this article, we present three independent arguments against the normic de minimis expected utility theory, focusing on its reliance on the de minimis principle.

Many people are worried about the harmful effects of climate change but nevertheless enjoy some activities that contribute to the emission of greenhouse gas (driving, flying, eating meat, etc.), the main cause of climate change. How should such people make choices between engaging in and refraining from enjoyable greenhouse-gas-emitting activities? In this chapter, we look at the answer provided by decision theory. Some scholars think that the right answer is given by interactive decision theory, or game theory; and moreover think that since private climate decisions are instances of the prisoner’s dilemma, one rationally should engage in these activities provided that one enjoys them. Others think that the right answer is given by expected utility theory, the best-known version of individual decision theory under risk and uncertainty. In this chapter, we review these different answers, with a special focus on the latter answer and the debate it has generated.

Bartha and DesRoches (Synthese 199(3–4):8701–8740, 2021) and Steel and Bartha (Risk Analysis 43(2):260–268, 2023) argue that we should understand the precautionary principle as the injunction to maximise lexical utilities. They show that the lexical utility model has important pragmatic advantages. Moreover, the model has the theoretical advantage of satisfying all axioms of expected utility theory except continuity. In this paper I raise a trilemma for any attempt at modelling the precautionary principle with lexical utilities: it permits choice cycles or leads to paralysis or implies that the smallest value difference that is possible in a context has extreme axiological implications.

According to a common judgement, a social planner should often use a lottery to decide which of two people should receive a good. This judgement undermines one of the best-known arguments for utilitarianism, due to John C. Harsanyi, and more generally undermines axiomatic arguments for utilitarianism and similar views. In this paper we ask which combinations of views about (a) the social planner’s attitude to risk and inequality, and (b) the subjects’ attitudes to risk are consistent with the aforementioned judgement. We find that the class of combinations of views that can plausibly accommodate this judgement is quite limited. But one theory does better than others: the theory of chance-sensitive utility.

I defend a weak version of the Pigou-Dalton principle for chances. The principle says that it is better to increase the survival chance of a person who is more likely to die rather than a person who is less likely to die, assuming that the two people do not differ in any other morally relevant respect. The principle justifies plausible moral judgements that standard ex post views, such as prioritarianism and rank-dependent egalitarianism, cannot accommodate. However, the principle can be justified by the same reasoning that has recently been used to defend the core axiom of ex post prioritarianism and egalitarianism, namely, Pigou-Dalton for well-being. The arguably biggest challenge for proponents of Pigou-Dalton for chances is that it violates State Dominance for social prospects. However, I argue that we have independent reason for rejecting State Dominance for social prospects, since it prevents a social planner from properly respecting people's preferences.

Many philosophers think that we should use a lottery to decide who gets a good to which two persons have an equal claim but which only one person can get. Some philosophers think that we should save identified persons from harm even at the expense of saving a somewhat greater number of statistical persons from the same harm. I defend a principled way of justifying both judgements, namely, by appealing to the decreasing marginal moral value of survival chances. I identify four desiderata that, I contend, any such justification should satisfy, and explain how my account meets these desiderata, unlike some previous accounts.

A social planner who evaluates risky public policies in light of the other risks with which their society will be faced should judge favourably some such policies even though they would deem them too risky when considered in isolation. I suggest that a longtermist would—or at least should—evaluate risky polices in light of their prediction about future risks; hence, longtermism supports social risk-taking. I consider two formal versions of this argument, discuss the conditions needed for the argument to be valid, and briefly compare these conditions to some risky policy options with which actual public decision-makers are faced.

Laurie Paul argues that, when it comes to many of your most significant life-changing decisions, the principles of rational choice are silent. That is because, in these cases, you anticipate that one of your choice options would yield a transformative experience. We argue that such decisions are best seen as ones in which you anticipate awareness growth. You do not merely lack knowledge about which possible outcome will arise from a transformative option; you lack knowledge about what are the possible outcomes. We show how principles of rational choice can be extended to cases of anticipated awareness growth.

ABSTRACT Offsetting is a very ineffective way to do good. Offsetting your lifetime emissions may increase aggregated life expectancy by at most seven years, while giving the amount it costs to offset your lifetime emissions to a malaria charity saves in expectation the life of at least one child. Is there any moral reason to offset rather than giving to some charity that does good so much more effectively? There might be such a reason if your offsetting compensated or somehow benefitted the victims of your emission, since that could mean that you would satisfy the duty not to harm others by emitting and offsetting. But that is typically not true. If your emission harms some person and your offsetting benefits some person, then these are most likely different people. Hence, I conclude, we have a stronger reason to give to effective charities than we have to offset our emissions.

Neoclassical economists use expected utility theory to explain, predict, and prescribe choices under risk, that is, choices where the decision-maker knows---or at least deems suitable to act as if she knew---the relevant probabilities. Expected utility theory has been subject to both empirical and conceptual criticism. This chapter reviews expected utility theory and the main criticism it has faced. It ends with a brief discussion of subjective expected utility theory, which is the theory neoclassical economists use to explain, predict, and prescribe choices under uncertainty, that is, choices where the decision-maker cannot act on the basis of objective probabilities but must instead consult her own subjective probabilities.

The de minimis principle states that some risks are so trivial that they can be ignored or treated categorically differently from non-trivial risks. Lundgren and Stefánsson criticize the de minimis principle, arguing that it either has to be applied locally or globally and that problems arise whichever application is chosen. Aven and Seif respond to Lundgren and Stefánsson’s argument and defend the de minimis principle as a “meaningful and useful perspective for handling risk in practice.” The response highlights some aspects of the argument in Lundgren and Stefánsson that needs clarification, which is what we do in this note.

This paper presents a new kind of problem in the ethics of distribution. The problem takes the form of several “calibration dilemmas,” in which intuitively reasonable aversion to small-stakes inequalities requires leading theories of distribution to recommend intuitively unreasonable aversion to large-stakes inequalities. We first lay out a series of such dilemmas for prioritarian theories. We then consider a widely endorsed family of egalitarian views and show that they are subject to even more forceful calibration dilemmas than prioritarian theories. Finally, we show that our results challenge common utilitarian accounts of the badness of inequalities in resources.

Both individuals and governments around the world have willingly sacrificed a great deal to meet the collective action problem posed by Covid-19. This has provided some commentators with newfound hope about the possibility that we will be able to solve what is arguably the greatest collective action problem of all time: global climate change. In this paper we argue that this is overly optimistic. We defend two main claims. First, these two collective action problems are so different that the actions that individuals have taken to try to solve the problem posed by Covid-19 unfortunately provide little indication that we will be able to solve the problem posed by climate change. Second, the actions that states have taken in response to Covid-19 might—if anything—even be evidence that they will continue to fail to cooperate towards a solution to the climate crisis.

Economic policy evaluations require social welfare functions for variable-size populations. Two important candidates are critical-level generalized utilitarianism (CLGU) and rank-discounted critical-level generalized utilitarianism, which was recently characterized by Asheim and Zuber (2014) (AZ). AZ introduce a novel axiom, existence of egalitarian equivalence (EEE). First, we show that, under some uncontroversial criteria for a plausible social welfare relation, EEE suffices to rule out the Repugnant Conclusion of population ethics (without AZ’s other novel axioms). Second, we provide a new characterization of CLGU: AZ’s set of axioms is equivalent to CLGU when EEE is replaced by the axiom same-number independence.

Suppose that a decision-maker's aim, under certainty, is to maximise some continuous value, such as lifetime income or continuous social welfare. Can such a decision-maker rationally satisfy what has been called "continuity for easy cases" while at the same time satisfying what seems to be a widespread intuition against the full-blown continuity axiom of expected utility theory? In this note I argue that the answer is "no": given transitivity and a weak trade-off principle, continuity for easy cases violates the anti-continuity intuition. I end the note by exploring an even weaker continuity condition that is consistent with the aforementioned intuition.

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.