A name given by John L. Austin to messages that are appropriate to ask whether they are true or false (for example, “the cat is on the mat”).
Austin was mostly interested in performative utterances (statements that make no sense to ask whether they are true or false, such as “I name this child Alexander”, uttered by a priest in the current circumstances when performing a baptismal ritual).
Performative utterances can be wrong in one way or another (for example, when bidding in an auction, I could be wrong to deny the validity of my statement), but they can still be neither true nor false. Ultimately, Austin has tested the simplistic ways in which we traditionally think of language.
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