Abstract
An increasingly popular view in the literature on rationality attempts to vindicate the strong normativity of rationality by giving a unifying account of rational requirements and what one ought to do in terms of reasons that fall within one’s perspective. In this paper, I pose a dilemma for such a view: one’s rationality is determined by a narrower set of reasons, such as the set of reasons that one is attending to, whereas what one ought to do is determined by a broader set of reasons that comprises reasons one is not attending to. Thus, no single set of reasons can play the dual role of determining what one is rationally required to do and determining what one ought to do: either it is too broad to determine what one is rationally required to do or it is too narrow to determine what one ought to do. [*published with open access]