Promises as Proposals in Joint Practical Deliberation

This paper argues that promises are proposals in joint practical deliberation, the activity of deciding together what to do. More precisely: to promise to ϕ is to propose (in a particular way) to decide together with your addressee(s) that you will ϕ. I defend this deliberative theory by showing that the activity of joint practical deliberation naturally gives rise to a speech act with exactly the same properties as promises. A certain kind of proposal to make a joint decision regarding one's own actions turns out to have the very same normative effects, under the very same conditions, as a promise. I submit that this cannot be a coincidence: we should conclude that promises and the relevant kind of proposals in joint practical deliberation are one and the same.