The ground has now been prepared for a full dress analysis of the illocutionary act. I shall take promising as my initial quarry, because as illocutionary acts go, it is fairly formal and well articulated; like a mountainous terrain, it exhibits its geographical features starkly. But we shall see that it has more than local interest, and many of the lessons to be learned from it are of general application.

In order to give an analysis of the illocutionary act of promising I shall ask what conditions are necessary and sufficient for the act of promising to have been successfully and non-defectively performed in the utterance of a given sentence. I shall attempt to answer this question by stating these conditions as a set of propositions such that the conjunction of the members of the set entails the proposition that a speaker made a successful and non-defective promise, and the proposition that the speaker made such a promise entails this conjunction. Thus each condition will be a necessary condition for the successful and non-defective performance of the act of promising, and taken collectively the set of conditions will be a sufficient condition for such a performance. There are various kinds of possible defects of illocutionary acts but not all of these defects are sufficient to vitiate the act in its entirety. In some cases, a condition may indeed be intrinsic to the notion of the act in question and not satisfied in a given case, and yet the act will have been performed nonetheless.