IS THERE A NEXUS BETWEEN REASONS AND

When we say that a subject has attitudes that she is rationally required to have, does that entail that she has those attitudes for reasons? In other words, is there a deep nexus between being rational and responding to reasons? Many have argued that there is. Derek Parfit, for example, tells us that “to be rational is to respond to reasons ” (Parfit 1997, p. 99). But I am not so sure. I begin by considering this question in the domain of theoretical rationality. The question in this domain is whether, when a subject has the beliefs that she is required to have by the norms of theoretical rationality, she is responding to reasons that there are for having those beliefs. Armed with a moderately clear answer to this question in the theoretical domain, I consider their relationship in the practical domain. When a subject has the desires that she is required to have by the norms of practical rationality, is she responding to reasons that there are for having those desires? Part of the interest of these questions lies in improving our understanding of reasons for action. I will say a little about this towards the end. 1. Reasons and Rationality in the Theoretical Domain Let’s begin with a very simple case of theoretically rational belief formation. Suppose that the following is true: TR: Reason requires that if I believe that p and I believe that if p then q, then I believe that q. Furthermore, suppose that I believe that p, and that I believe that if p then q, and that, abiding by TR, I rationally go on to form the belief that q – let’s just assume whatever else needs to be true for this to be the case. Fragments marked purple should be changed or supplemented. Fragments marked yellow need an approval from the authors because either have been changed/added or there are some doubts about them. Exactly these colors are choosed to be distinguishable on a black-white printout. In unclear situations there are comments on the margins