Illocutionary act

The concept of illocutionary acts was introduced into linguistics by the philosopher John L. Austin in his investigation of the various aspects of speech acts. In Austin's framework, locution is what was said, illocution is what was meant, and perlocution is what happened as a result. For example, when somebody says "Is there any salt?" at the dinner table, the illocutionary act (the meaning conveyed) is effectively "please give me some salt" even though the locutionary act (the literal sentence) was to ask a question about the presence of salt. The perlocutionary act (the actual effect), was to cause somebody to offer salt.

The notion of an illocutionary act is closely connected with Austin's doctrine of the so-called 'performative' and 'constative utterances': an utterance is "performative" if, and only if it is issued in the course of the "doing of an action" (1975, 5), by which, again, Austin means the performance of an illocutionary act (Austin 1975, 6 n2, 133). According to Austin's original exposition in How to Do Things With Words, an illocutionary act is an act (1) for the performance of which I must make it clear to some other person that the act is performed (Austin speaks of the 'securing of uptake'), and (2) the performance of which involves the production of what Austin calls 'conventional consequences' as, e.g., rights, commitments, or obligations (Austin 1975, 116f., 121, 139). Thus, for example, in order to make a promise I must make clear to my audience that the act I am performing is the making of a promise, and in the performance of the act I will be undertaking an obligation to do the promised thing: so promising is an illocutionary act in the present sense. Since Austin's death, the term has been defined differently by various authors.

One way to think about the difference between an illocutionary act (e.g., a declaration, command, or a promise), and a perlocutionary act (e.g., an insult or a persuasion attempt) is to note how in the former case, by uttering the object—for example, "I hereby declare," or "I command," or "I hereby promise you"—the act has taken place. That is to say, in each case a declaration, command, or promise has necessarily taken place in virtue of the utterance itself, whether the hearer believes in the declaration, command, or promise or not. On the other hand, with a perlocutionary act, the object of the utterance has not taken place unless the hearer deems it so—for example, if one utters, "I hereby insult you," or "I hereby persuade you," one would not assume an insult has necessarily occurred, nor persuasion has necessarily taken place, unless the hearer were suitably offended or persuaded by the utterance.

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