Performative utterance

In the philosophy of language and speech acts theory, performative utterances are sentences which are not only describing a given reality, but also changing the social reality they are describing.

In his 1955 William James lecture series, which were later published under the title How to Do Things with Words, J. L. Austin argued against a positivist philosophical claim that the utterances always "describe" or "constate" something and are thus always true or false. After mentioning several examples of sentences which are not so used, and not truth-evaluable (among them non-sensical sentences, interrogatives, directives and "ethical" propositions), he introduces "performative" sentences or Illocutionary act as another instance.

In order to define performatives, Austin refers to those sentences which conform to the old prejudice in that they are used to describe or constate something, and which thus are true or false; and he calls such sentences "constatives". In contrast to them, Austin defines "performatives" as follows:

For example, when Peter says "I promise to do the dishes" in an appropriate context then he thereby does not just say something, and in particular he does not describe what he is doing; rather, in making the utterance he performs the promise; since promising is an illocutionary act, the utterance is thus a performative utterance. If Peter utters the sentence without the intention to keep the promise, or if eventually he does not keep it, then although something is not in order with the utterance, the problem is not that the sentence is false: it is rather "unhappy", or "infelicitous", as Austin also says in his discussion of so-called felicity conditions. In the absence of any such flaw, on the other hand, the utterance is to be assessed as "happy" or "felicitous", rather than as "true". Austin dropped this distinction in favour of a distinction between explicit performatives ("I promise it will never happen again") and primary or implicit performatives ("It will never happen again," functioning as a promise).

...
Wikipedia