AAP 2026 CONFERENCE

In this paper, I discuss preferences over gambles that seem intuitively rational, and that many real-world agents hold, but that deviate from orthodox normative decision theory. These preferences even deviate from the various less orthodox decision theories designed to accommodate risk aversion. This is because such preferences exhibit not risk aversion, but instead regret aversion: a preference for one’s chosen option to be more likely to actually turn out better (or perhaps significantly better) than the alternatives. Is regret aversion rational? Plausibly, yes. Beyond mere intuitions about cases, I offer two further motivations. The first is that regret aversion is needed to reflect at least some concern for doing what is objectively best, and it is plausible that such a concern is rational (perhaps even rationally required), especially in moral decision-making. The second motivation is that regret aversion correctly diagnoses and treats what’s wrong with so-called ‘fanatical’ verdicts in cases of extremely low probabilities and extremely high stakes. There are also reasons to think regret aversion irrational: it leads to violations of several widely-held and seemingly plausible principles of rationality. Perhaps these violations constitute a decisive objection to regret aversion. Or, perhaps, regret aversion constitutes a decisive objection to all normative decision theories so far proposed.