Abstract
This paper will give an account as to how action is possible as an event. The fact that meaning of action is necessarily CONTINGENT forces us into reconceptualizing RULE (1). After overlooking speech-act theory, according to which MEANING of action is <force> as distinct from <sense> of word (2), then, to meet its difficulty, the levels of speech act and of action as an event with a certain force will be differenciated. As for the latter, how it occurs will be considered by reference to <conversation analysis>, whose methode was systematically established by H. Sacks and his colleagues (3). In the last analysis, three rules will be given : <turn-taking system> at the most basic level; <adjacency pairs> and constitutive rules for speech act at the middle level. Action is constituted by the parties themselves managing interactively the process of the constitution, EXPLOITING the rules.