This dissertation presents and defends an ethical outlook based on two guiding ideas: first, there is a plurality of rationally permissible attitudes towards risks that involve our welfare or well-being; and second, an ethical deliberator should defer to rational individuals’ attitudes towards risk when assessing policies with uncertain consequences that affect them. John Harsanyi famously argued that deferring to people’s preferences under risk leads to utilitarianism. Amartya Sen and John Weymark pointed out that Harsanyi’s argument relies on a contentious interpretation of decision theory under risk—according to which, effectively, only one attitude towards risks involving our well-being, that of risk neutrality, is rationally permissible. As the Sen-Weymark critique clarifies, Harsanyi’s stance is untenable if our quantitative notion of well-being is independent of preferences formed in conditions of risk.
 

Chapter 1 argues that this is indeed the case: our quantitative notion of well-being depends on comparisons between outcomes with no uncertainty. It defends a method for deriving quantities of well-being based on conjoint measurement between objective goods. 

Chapter 2 explores the space of possibilities that our two guiding ideas leave us with; it shows that under weak assumptions they are incompatible with welfarism, the view that all we need to know in order to evaluate outcomes is how people’s well-being is distributed. It then presents a dilemma for non-welfarist views: they either entail that risk attitudes affect the moral significance of well-being in contexts of zero risk, or they struggle to vindicate the thought that improving everyone’s well-being is an important ethical concern. 

Chapter 3 sides with the first horn of this dilemma. It offers a defense of a position I call the Risk-Priority View: on this theory, the ethical import of an individual ending up with a certain amount of well-being is affected by that individual’s risk attitude. Roughly, more risk-averse individuals get priority in dire circumstances, while more risk-seeking individuals get priority in favorable ones.