Abstract

The norms of rationality determine whether an act is irrational, rationally required, or rationally optional. It has seemed theoretically difficult to make significant room for the last category, because rational status is typically taken to be a function of reasons, and reasons are typically taken to have univocal strength values. But there is also a strong intuition that normal choice situations present us with many equally rational options. If this intuition is correct, two questions arise. The first is how it could be true, assuming that rational status is indeed a function of reasons. The second is whether and how we can act in a non-arbitrary way when we are faced with a choice between a number of equally rational options. This chapter examines four strategies for addressing these questions: incommensurability of reasons, parity, the ubiquity of ties, and a distinction between the justifying and requiring roles of practical reasons.