Perlocutionary act

A perlocutionary act (or perlocutionary effect) is a speech act, as viewed at the level of its consequences, such as persuading, convincing, scaring, enlightening, inspiring, or otherwise affecting the listener. This is contrasted with locutionary and illocutionary acts (which are levels of description, rather than classifications of speech acts).

Unlike the notion of illocutionary act, which describes the linguistic function of an utterance, a perlocutionary effect is in some sense external to the performance. It may be thought of, in a sense, as the effect of the illocutionary act via the locutionary act. Therefore, when examining perlocutionary acts, the effect on the hearer or reader is emphasized.

As an example, consider the following utterance: "By the way, I have a CD of Debussy; would you like to borrow it?" Its illocutionary function is an offer, while its intended perlocutionary effect might be to impress the listener, or to show a friendly attitude, or to encourage an interest in a particular type of music.

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