A speech act in linguistics and the philosophy of language is an utterance that has performative function in language and communication. According to Kent Bach, "almost any speech act is really the performance of several acts at once, distinguished by different aspects of the speaker's intention: there is the act of saying something, what one does in saying it, such as requesting or promising, and how one is trying to affect one's audience". The contemporary use of the term goes back to J. L. Austin's development of performative utterances and his theory of locutionary, illocutionary, and perlocutionary acts. Speech acts are commonly taken to include such acts as promising, ordering, greeting, warning, inviting and congratulating.
Speech acts can be analysed on three levels:
The concept of an illocutionary act is central to the concept of a speech act. Although there are numerous opinions regarding how to define 'illocutionary acts', there are some kinds of acts which are widely accepted as illocutionary, as for example promising or commanding.
Following the usage of, for example, John R. Searle, "speech act" is often meant to refer just to the same thing as the term illocutionary act, which John L. Austin had originally introduced in How to Do Things with Words (published posthumously in 1962). Searle's work on speech acts is also commonly understood to refine Austin's conception. However, some philosophers have pointed out a significant difference between the two conceptions: whereas Austin emphasized the conventional interpretation of speech acts, Searle emphasized a psychological interpretation (based on beliefs, intentions, etc.).
According to Austin's preliminary informal description, the idea of an "illocutionary act" can be captured by emphasizing that "by saying something, we do something", as when someone issues an order to someone to go by saying "Go!", or when a minister joins two people in marriage saying, "I now pronounce you husband and wife." (Austin would eventually define the "illocutionary act" in a more exact manner.)
An interesting type of illocutionary speech act is that performed in the utterance of what Austin calls performatives, typical instances of which are "I nominate John to be President", "I sentence you to ten years' imprisonment", or "I promise to pay you back." In these typical, rather explicit cases of performative sentences, the action that the sentence describes (nominating, sentencing, promising) is performed by the utterance of the sentence itself.
While illocutionary acts relate more to the speaker, perlocutionary acts are centered around the listener. Perlocutionary acts always have a 'perlocutionary effect' which is the effect a speech act has on a listener. This could affect the listener's thoughts, emotions or even their physical actions. An example of this could be if someone uttered the sentence "I'm hungry." The perlocutionary effect on the listener would persuade them to maybe make a sandwich for the speaker.
In the course of performing speech acts we ordinarily communicate with each other. The content of communication may be identical, or almost identical, with the content intended to be communicated, as when a stranger asks, "What is your name?"
However, the meaning of the linguistic means used (if ever there are linguistic means, for at least some so-called "speech acts" can be performed non-verbally) may also be different from the content intended to be communicated. One may, in appropriate circumstances, request Peter to do the dishes by just saying, "Peter ...!", or one can promise to do the dishes by saying, "Me!" One common way of performing speech acts is to use an expression which indicates one speech act, and indeed performs this act, but also performs a further speech act, which is indirect. One may, for instance, say, "Peter, can you close the window?", thereby asking Peter whether he will be able to close the window, but also requesting that he does so. Since the request is performed indirectly, by means of (directly) performing a question, it counts as an indirect speech act.
An even more indirect way of making such a request would be to say, in Peter's presence in the room with the open window, "I'm cold." The speaker of this request must rely upon Peter's understanding of several items of in-explicit information: that the window is open and is the cause of her being cold, that being cold is an uncomfortable sensation and she wishes it to be taken care of, and that Peter cares to rectify this situation by closing the window. This, of course, depends much on the relationship between the requester and Peter—he might understand the request differently if she were his boss at work than if she were his girlfriend at home. The more presumed information pertaining to the request, the more indirect the speech act may be considered to be.
Indirect speech acts are commonly used to reject proposals and to make requests. For example, a speaker asks, "Would you like to meet me for coffee?" and another replies, "I have class." The second speaker used an indirect speech act to reject the proposal. This is indirect because the literal meaning of "I have class" does not entail any sort of rejection.
This poses a problem for linguists because it is confusing (on a rather simple approach) to see how the person who made the proposal can understand that his proposal was rejected. Following substantially an account of H. P. Grice, Searle suggests that we are able to derive meaning out of indirect speech acts by means of a cooperative process out of which we are able to derive multiple illocutions; however, the process he proposes does not seem to accurately solve the problem. Sociolinguistics has studied the social dimensions of conversations. This discipline considers the various contexts in which speech acts occur.
In other words this means that one does not need to say the words apologize, pledge, or praise in order to show they are doing the action. All the examples above show how the actions and indirect words make something happen rather than coming out straightforward with specific words and saying it.
For much of the history of linguistics and the positivist philosophy of language, language was viewed primarily as a way of making factual assertions, and the other uses of language tended to be ignored, as Austin states at the beginning of Lecture 1, "It was for too long the assumption of philosophers that the business of a 'statement' can only be to 'describe' some state of affairs, or to 'state some fact', which it must do either truly or falsely." Wittgenstein came up with the idea of "don't ask for the meaning, ask for the use," showing language as a new vehicle for social activity. Speech act theory hails from Wittgenstein’s philosophical theories. Wittgenstein believed meaning derives from pragmatic tradition, demonstrating the importance of how language is used to accomplish objectives within specific situations. By following rules to accomplish a goal, communication becomes a set of language games. Thus, utterances do more than reflect a meaning, they are words designed to get things done. The work of J. L. Austin, particularly his How to Do Things with Words, led philosophers to pay more attention to the non-declarative uses of language. The terminology he introduced, especially the notions "locutionary act", "illocutionary act", and "perlocutionary act", occupied an important role in what was then to become the "study of speech acts". All of these three acts, but especially the "illocutionary act", are nowadays commonly classified as "speech acts".
Austin was by no means the first one to deal with what one could call "speech acts" in a wider sense. The term 'social act' and some of the theory of this sui generis type of linguistic action are to be found in the fifth of Thomas Reid's Essays on the Active Powers of the Human Mind (1788, chapter VI, Of the Nature of a Contract). "A man may see, and hear, and remember, and judge, and reason; he may deliberate and form purposes, and execute them, without the intervention of any other intelligent being. They are solitary acts. But when he asks a question for information, when he testifies a fact, when he gives a command to his servant, when he makes a promise, or enters into a contract, these are social acts of mind, and can have no existence without the intervention of some other intelligent being, who acts a part in them. Between the operations of the mind, which, for want of a more proper name, I have called solitary, and those I have called social, there is this very remarkable distinction, that, in the solitary, the expression of them by words, or any other sensible sign, is accidental. They may exist, and be complete, without being expressed, without being known to any other person. But, in the social operations, the expression is essential. They cannot exist without being expressed by words or signs, and known to the other party."
Adolf Reinach (1883–1917) and Stanislav Škrabec (1844–1918) have been both independently credited with a fairly comprehensive account of social acts as performative utterances dating to 1913, long before Austin and Searle.
The term metalocutionary act has also been used to indicate a speech act that refers to the forms and functions of the discourse itself rather than continuing the substantive development of the discourse, or to the configurational functions of prosody and punctuation.
Dore (1975) proposed that children's utterances were realizations of one of nine primitive speech acts:
There is no agreed formalization of Speech Act theory. A first attempt to give some grounds of an illocutionary logic has been given by John Searle and D. Vandervecken 1985. Other attempts have been proposed by Per Martin-Löf for a treatment of the concept of assertion inside intuitionistic type theory, and by Carlo Dalla Pozza, with a proposal of a formal pragmatics connecting propositional content (given with classical semantics) and illocutionary force (given by intuitionistic semantics). Up to now the main basic formal application of speech act theory are to be found in the field of human-computer interaction (in chatboxes and other tools: see below).
Another highly-influential view of Speech Acts has been in the 'Conversation for Action' developed by Terry Winograd and Fernando Flores in their 1987 text "Understanding Computers and Cognition: A New Foundation for Design". Arguably the most important part of their analysis lies in a state-transition diagram (in Chapter 5) that Winograd and Flores claim underlies the significant illocutionary (speech act) claims of two parties attempting to coordinate action with one another (no matter whether the agents involved might be human–human, human–computer, or computer–computer).
A key part of this analysis is the contention that one dimension of the social domain-tracking the illocutionary status of the transaction (whether individual participants claim that their interests have been met, or not) is very readily conferred to a computer process, regardless of whether the computer has the means to adequately represent the real world issues underlying that claim. Thus a computer instantiating the 'conversation for action' has the useful ability to model the status of the current social reality independent of any external reality on which social claims may be based.
This transactional view of speech acts has significant applications in many areas in which (human) individuals have had different roles—for instance, a patient and a physician might meet in an encounter in which the patient makes a request for treatment, the physician responds with a counter-offer involving a treatment she feels is appropriate, and the patient might respond, etc. Such a "Conversation for Action" can describe a situation in which an external observer (such as a computer or health information system) may be able to track the ILLOCUTIONARY (or Speech Act) STATUS of negotiations between the patient and physician participants even in the absence of any adequate model of the illness or proposed treatments. The key insight provided by Winograd and Flores is that the state-transition diagram representing the SOCIAL (Illocutionary) negotiation of the two parties involved is generally much, much simpler than any model representing the world in which those parties are making claims; in short, the system tracking the status of the 'conversation for action' need not be concerned with modeling all of the realities of the external world. A conversation for action is critically dependent upon certain stereotypical CLAIMS about the status of the world made by the two parties. Thus a "Conversation for Action" can be readily tracked and facilitated by a device with little or no ability to model circumstances in the real world other than the ability to register claims by specific agents about a domain.
In making useful applications of technology to domains such as healthcare, it is helpful to discriminate between problems which are very, very hard (such as deep understanding of pathophysiology as it relates to genetic and various environmental influences) and problem which are relatively easier, such as following the status of negotiations between a patient and a health care provider. Speech Act (Illocutionary) Analysis allows for a useful understanding of the status of a negotiation between (for instance) a health care provider and a patient INDEPENDENT of any well-accepted credible and comprehensive understanding of a disease process as it might apply to that patient. For this reason, systems which track the status of PROMISES and REJECTED-PROPOSALS and ACCEPTED-PROMISES can help us to understand the situations in which (human or computer) AGENTS find themselves as they attempt to fulfill ROLES involving other agents, and such systems can facilitate both human and human–computer systems in achieving role-associated goals.
In the past, philosophy has discussed rules for when expressions are used. The two rules are constitutive and regulative rules.
Multi-agent systems sometimes use speech act labels to express the intent of an agent when it sends a message to another agent. For example the intent "inform" in the message "inform(content)" may be interpreted as a request that the receiving agent adds the item "content" to its knowledge-base; this is in contrast to the message "query(content)" which may be interpreted (depending on the semantics employed) as a request to see if the item content is currently in the receiving agents knowledge base. There are at least two standardisations of speech act labelled messaging KQML and FIPA.
KQML and FIPA are based on the Searlian, that is, psychological semantics of speech acts. Munindar P. Singh has long advocated moving away from the psychological to a social semantics of speech acts—one that would be in tune with Austin's conception. Andrew Jones has also been a critic of the psychological conception. A recent collection of manifestos by researchers in agent communication reflects a growing recognition in the multiagent systems community of the benefits of a social semantics.
In political science, the Copenhagen School adopts speech act as a form of felicitous speech act (or simply 'facilitating conditions'), whereby the speaker, often politicians or players, act in accordance to the truth but in preparation for the audience to take action in the directions of the player that are driven or incited by the act. This forms an observable framework under a specified subject matter from the player, and the audience who are 'under-theorised [would] remain outside of the framework itself, and would benefit from being both brought in and drawn out.' It is because the audience would not be informed of the intentions of the player, except to focus on the display of the speech act itself. Therefore, in the perspective of the player, the truth of the subject matter is irrelevant except the result produced via the audience.
The study of Speech Acts is prevalent in legal theory since laws themselves can be interpreted as speech acts. Laws issue out a command to their constituents which can be realized as an action. When forming a legal contract, speech acts can be made when people are making or accepting an offer. Considering the theory of freedom of speech, some speech acts may not be legally protected. For example, a death threat is a type of speech act and is considered to exist outside of the protection of freedom of speech as it is treated as a criminal act.
In finance, it is possible to understand mathematical models as speech acts: the notion of "financial Logos" is defined in Walter (2016) as the speech act of mathematical financial risk models. The action of the financial Logos on financial practices is the following: the framing of financial decision-making by risk modelling.