Abstract

In this paper, I draw a distinction between two fundamentally different kinds of commitments by highlighting some previously unnoticed subtleties in the pragmatics of "commissive" utterances. I argue that theories which seek to model all commitments on promises, or to ground them all on voluntary consent, can account only for one sort of obligation and not for the other. Since social groups are most perspicuously categorized in terms of the sorts of commitments that bind their members together, this puts me in a position to distinguish two importantly different kinds of social groups, which I call aggregations and associations. I try to show that this position can account for features of the normative structure of social groups that are overlooked by those theorists (e.g. Margaret Gilbert) who have attempted to offer a unitary, voluntarist account of the phenomena under investigation