<logic, pragmatics> sentences (or utterances) that serve more to do (than describe) something. Typically, these sentences are in the first person present noncontinuous, with a main verb that indicates a speech action. e.g. "I promise to come to your party" as opposed to the non-performative (or descriptive) "he promises...," or "I kick him". Performatives are important because they make us realize that many declarative sentences are not so much true or false as they are actions which are well or badly done (orders, appointments, christenings, exorcisms, rulings, sentences, etc.).
[A Philosophical Glossary]
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