Illocutionary Act

In speech-act theory, the term illocutionary act refers to the use of a sentence to express an attitude with a certain function or "force," called an illocutionary force, which differs from locutionary acts in that they carry a certain urgency and appeal to the meaning and direction of the speaker. 

Although illocutionary acts are commonly made explicit by the use of performative verbs like "promise" or "request," they can often be vague as in someone saying "I'll be there," wherein the audience cannot ascertain whether the speaker has made a promise or not.

In addition, as Daniel R. Boisvert observes in "Expressivism, Nondeclarative, and Success-Conditional Semantics" that we can use sentences to "warn, congratulate, complain, predict, command, apologize, inquire, explain, describe, request, bet, marry, and adjourn, to list just a few specific kinds of illocutionary act."

The terms illocutionary act and illocutionary force were introduced by British linguistic philosopher John Austin in 1962's "How to Do Things With Words, and for some scholars, the term illocutionary act is virtually synonymous with speech act.

Locutionary, Illocutionary, and Perlocutionary Acts

Acts of speech can be broken down into three categories: locutionary, illocutionary, and perlocutionary acts. In each of these, too, the acts can either be direct or indirect, which quantify how effective they are at conveying the speaker's message to its intended audience.

According to Susana Nuccetelli and Gary Seay's "Philosophy of Language: The Central Topics," locutionary acts are "the mere act of producing some linguistic sounds or marks with a certain meaning and reference," but these are the least effective means of describing the acts, merely an umbrella term for the other two which can occur simultaneously.

Speech acts can therefore further be broken down into illocutionary and perlocutionary wherein the illocutionary act carries a directive for the audience, such as promising, ordering, apologizing and thanking. Perlocutionary acts, on the other hand, bring about consequences to the audiences such as saying "I will not be your friend." In this instance, the impending loss of friendship is an illocutionary act while the effect of frightening the friend into compliance is a perlocutionary act.

Relationship Between Speaker and Listener

Because perlocutionary and illocutionary acts depend on the audience's reaction to a given speech, the relationship between speaker and listener is important to understand in the context of such acts of speech.

Etsuko Oishi wrote in "Apologies," that "the importance of the speaker's intention in performing an illocutionary act is unquestionable, but, in communication, the utterance becomes an illocutionary act only when the hearer takes the utterance as such." By this, Oishi means that although the speaker's act may always be an illocutionary one, the listener can choose to not interpret that way, therefore redefining the cognitive configuration of their shared outer world.

Given this observation, the old adage "know your audience" becomes especially relevant in understanding discourse theory, and indeed in composing a good speech or speaking well in general. In order for the illocutionary act to be effective, the speaker must use language which his or her audience will understand as intended.