Of the five types of speech act possible for a human being to make, the commissive is most fundamental to the social contract, and to the idea of conversation. One's commitments tell others who one is and what can be expected of one when facing an unanticipated situation or an unknown circumstance.

The commissive has the basic form

(1) Commit oneself in the future (x)

where x is a propositional content of some sort. Thus

(A) Promise (I come to the party tonight), or

(B) Commit (I utter true judgments in conversation).

Deontic status (one's commitments and entitlements) is of fundamental importance in social life, and in formal conversation, and is underwritten by all of the commissives one has ever uttered or implicated in public circumstances.