Journal of the History of Philosophy

This paper is concerned to bring out the philosophical contribution that Thomas Reid makes in his discussions of promising. Reid discusses promising in two contexts: he argues that the practice of promising presupposes the belief that the promisor is endowed with what he calls 'active power' (EAP, IV.6), and he argues against Hume's claim that the very act of promising—and the obligation to do as one promised—are "artificial," or the products of human convention (EAP, V.6). In addition to explaining what Reid says in each of these two contexts, the paper demonstrates that the two discussions are linked. It is, in part, because he thinks that promises are a special kind of act (they are what he calls 'social acts', which he contrasts with 'solitary acts')—performable solely through the exercise of our native, natural capacities—that he thinks that the practice of promising presupposes active power. Towards this end, the paper explains how Reid conceives of active power and explains his concept of a social act. The paper argues that, when considered as part of a single, unitary conception of the nature of promises, Reid's two discussions provide important insights into the nature of promising, particularly with regard to the sense in which promisory obligations are conditional: they are conditional upon a rather short list of circumstances that are not within our power—a shorter list than those on which other obligations are conditional.