1 The Hybrid Nature of Promissory Obligation Neal A. Tognazzini neal.tognazzini@wwu.edu Penultimate version Final version in Philosophy & Public Affairs http://philpapers.org/rec/TOGTHN I. Promises and Our Social Practice Promises are curious acts of communication. Simple words uttered; binding obligations created. How are promissory obligations created, seemingly out of thin air? The answer is by no means uncontroversial. Many have thought that promissory obligation only makes sense against the background of a social practice of promising. According to these theorists, when one breaks a promise, the wrong that one commits is the wrong of undermining or exploiting a just social practice for one’s own benefit. 1 Surely that is not all there is to promising, however. After all, when I make a promise to you and then break it, it seems that I have wronged you in some way. A ‘social practice view’ cannot make sense of this aspect of promising if the wrong of promise-breaking is to be explained solely in terms of a social practice. If that were all there were to promissory obligation, then the force of my saying, “But you promised me you would do it!” would be no different than if my friend Robert found out that you broke your promise and said, “But you promised Neal you would do it!” When you break a promise to me, I have a special complaint against you that Robert does not have. 2 However, a social practice view cannot account for my having a special complaint. So, theorists have begun to move away