Margaret Gilbert

I argue that obligations of an important type inhere in what I call 'joint commitments'. I propose a joint commitment account of everyday agreements. This could explain why some philosophers believe that we know of the obligating nature of agreements a priori. I compare and contrast obligations of joint commitment with obligations in the relatively narrow sense recommended by H. L. A. Hart, a recommendation that has been influential. Some central contexts in which Hart takes there to be obligations in his sense are contexts in which there are obligations of joint commitment. Nonetheless, different senses of 'obligation' appear to be at issue

What is it to do something with another person? In the author's book On Social Facts and elsewhere, she has conjectured that a special type of commitment - joint commitment - lies at the root of acting together and many other central social phenomena. Here she surveys some data pertinent to this conjecture, including the assumption of those who act together that they have associated rights against and obligations towards each other. She explains what joint commitment is, how it relates to the data noted, and argues that an appeal to joint commitment does not involve a pernicious form of holism.

This article will compare and contrast two very different accounts of convention: the game-theoretical account of Lewis in Convention, and the account initially proposed by Margaret Gilbert (the present author) in chapter six of On Social Facts, and further elaborated here. Gilbert’s account is not a variant of Lewis’s. It was arrived at in part as the result of a detailed critique of Lewis’s account in relation to a central everyday concept of a social convention. An account of convention need not be judged by that standard. Perhaps it reveals the nature of an important phenomenon. Looked at in that light, these very different accounts are not incompatible. Indeed, neither should be ignored if one is seeking to understand the way in which human beings arrive at some degree of social order.