What if ideal advice conflicts? A dilemma for idealizing accounts of normative practical reasons

One of the deepest and longest-lasting debates in ethics concerns a version of the Euthyphro question: are choiceworthy things choiceworthy because agents have certain attitudes toward them or are they choiceworthy independent of any agents’ attitudes? Reasons internalists, such as Bernard Williams, Michael Smith, Mark Schroeder, Sharon Street, Kate Manne, Julia Markovits, and David Sobel answer in the first way. They think that all of an agent’s normative reasons for action are grounded in facts about that agent’s pro-attitudes (e.g., her desires, valuing states, normative judgments). According to the most popular brand of internalism, idealizing internalism, an agent’s reasons are grounded, not in her actual pro-attitudes, but rather in what her pro-attitudes would be in suitably idealized conditions. Idealizing internalists presuppose that, for any agent with an irrational set of attitudes, there is one uniquely rational set that that agent would have if she were to undergo the relevant idealizing process. I argue that this assumption is false and that it raises two puzzles for idealizing internalism: one about the existence of practical reasons and another about their normative weight. I argue that idealizing internalists have an adequate solution to the first puzzle but not the second. Indeed, when they try to solve the second puzzle, they confront a dilemma. This second puzzle and the associated dilemma thus constitutes a powerful, but so far unnoticed, difficulty for idealizing internalism.