The prevailing sense of "discourse" is defined by the OED as "A spoken or written treatment of a subject, in which it is handled or discussed at length; a dissertation, treatise, homily, sermon, or the like." While previous, archaic definitions of discourse have been "process or succession of time, events, actions, etc." or "the act of understanding," discourse is most simply understood today as a sort of unit of language organized around a particular subject matter and meaning. This can be contrasted to other ways in which language has been broken down into much smaller units of analysis, such as into individual words or sentences in studies of semantics and syntax. Furthermore, as opposed to the linguistic conception of language as a generally stable, unified, abstract symbolic system, discourse denotes real manifestations of language--actual speech or writing.
In addition, the idea of discourse often signifies a particular awareness of social influences on the use of language. It is therefore important to distinguish between discourse and the Saussurean concept of the parole as a real manifestation of language (Saussure, 11-17). Saussure's distinction between langue and parole is such: langue is a linguistic system or code which is prior to the actual use of language and which is stable, homogenous and equally accessible to all members of a linguistic community. Parole is what is actually spoken or written, and varies according to individual choice. Thus while discourse is also what is actually spoken or written, it differs from parole in that it is used to denote manifestations of language that are determined by social influences from society as a whole, rather than by individual agency.
Because the form that discourse takes cannot be solely the product of individual choice, the word entails a meaningful ambiguity between generality and specificity (Fairclough, 24). Discourse can refer either to what is conventionally said or written in a general context, or to what is said or written on a particular occasion of that context. One example of discourse in our culture is one that posits that being cold and wet can cause a person to develop a cold--a belief which doctors reject as unscientific. Yet if I specifically were to say, "I have a cold because I got caught in the rain last night," this would be also be an example of discourse. My words would reflect my own particularity by stating the fact that I, as an individual, had been caught in the rain last night--yet at the same time my words are determined by a social commonplace. The ambiguity exists between generality and specificity because the idea of discourse implies that the specific is also always general.
Yet while discourse most often denotes an instance of language, it is also important to note that in other frameworks, discourse is not necessarily a linguistic phenomenon; it can also be conceptualized as inhabiting a variety of other forms, such as visual and spatial (Fairclough, 22). For example, in his analysis of the development of the modern penal system Foucault cites the medical and juridical discourse about the necessity of rehabilitating criminals--but he also cites the actual structure of prisons, designed to maximize surveillance, as contributing to the discourse of this conceptualization of criminality (Foucault, 1975, 233-9).
The idea of discourse thus emphasizes that language is a social and communal practice, never external to or prior to society (as some conceptualizations of linguistics, such as Saussure's, may seem to assume). In semiotics, one way to conceptualize discourse, then, is to see it as a reflection of its particular context in a particular part of society. According to linguist Michael Halliday, discourse is "a unit of language larger than a sentence and which is firmly rooted in a specific context. There are many different types of discourse under this heading, such as academic discourse, legal discourse, media discourse, etc. Each discourse type possesses its own characteristic linguistic features" (Martin and Ringham, 51). This definition of discourse emphasizes the way in which social context--who is speaking, who is listening, and when and where the instance of language occurs--determines the nature of enunciations. It is clear how legal discourse and media discourse, will demonstrate fundamentally different conventions of style, wording, and other "linguistic features."
A more complex understanding of discourse emphasizes that formal conventions of the mode of expression are not the only aspect of language that is determined by the social. Underlying beliefs and worldviews, specific to the social context, are seen to be mediated by discourse. According to the Dictionary of Semiotics, discourse, "in strictly semiotic terms," does not refer to the literal or "narrative" level of language but to the interaction between "the figurative dimension, relating to the representation of the natural world" and "the thematic dimension, relating to the abstract values actualized in an utterance" (Martin and Ringham, 51). As evident in the previous example of the discourse that states that coldness and wetness can cause a cold, discourse entails underlying assumptions about the nature of the world and of particular social values and beliefs.
In contemporary continental philosophy, this understanding of discourse as the covert embodiment of social values is taken on a more critical, political level--discourse is seen by some philosophers as a means of the legitimization of social and political practices. The Italian Marxist Antonio Gramsci wrote about ideology as "a conception of the world that is implicitly manifest in art, in law, in economic activity and in all manifestations of individual and collective life" (Gramsci, 330). For him, discourse mediates ideological justifications of the status quo that come to be accepted as "common sense." Similarly, anthropologist Pierre Bourdieu wrote that the ultimate objective of a discourse is the "recognition of legitimacy through the misrecognition of arbitrariness" (Bourdieu, 163). Through the proliferation of discourse, beliefs and ideas that are actually socially and historically specific are legitimized by their seemingly universal and natural appearance. An example of this sort of discourse might be advertising discourse in capitalist society. Advertisements may portray luxury products as naturalized needs; this discourse thereby reinforces a consumption-driven culture.
Using a similar theory of discourse as ideology, Louis Althusser sees discourse as naturalizing "subject-positions," or social roles. Althusser writes, "Like all obviousnesses, including those that make a word 'name a thing' or 'have a meaning'... the 'obviousness' that you and I are subjects... is an ideological effect, the elementary ideological effect" (Althusser, 171-2). If subject positions are an ideological effect, then individuals are given social identities that are established by discourse, a discourse that at the same time naturalizes such subject positions and conceals this very process.
The discursive production of the subject has been theorized in other ways that do not utilize the concept of ideology. For Foucault, discourse is a medium through which power and norms function. Foucault describes how, in modernity, scientific discourses such as the "human sciences" which claim to reveal human nature actually establish norms and prescribe optimum modes of conduct. These discourses also establish ways of identifying, understanding, and managing "deviant" subjects. By describing and categorizing individuals in detail, these discourses exert an unprecedented amount of power over the individual's comportment and relationship to herself (Foucault, 1978, 92-114 and 1999, 39). For example, in The History of Sexuality, Foucault describes how psychological discourses actually produced a new understanding of personhood by creating the concept of sexuality as a fundamental marker of identity. Whereas previously, non-heterosexual acts were simply seen as against nature, under the new discourse they became psychologically deviant, indicating of a whole array of other psychological disturbances. The idea of the homosexual, the invert, and the sadomasochist developed, thereby constituting a new experience of the individual as a sexual being and, through its most minute descriptions of the meanings of sexuality, a tighter control over the subjective experiences of individuals.
While borrowing the Foucauldean concepts of power and the norm, Judith Butler takes a slightly different stance on the way in which discourse produces the subject. Butler is particularly interested in the embodiment of gender--a process that she calls performativity. Butler claims that gender identity is actually an ongoing process of "citing" gender norms that permeate society, mediated by a heteronormative discourse that describes masculinity and femininity as stable, natural, and mutually exclusive. In fact, a gender identity only seems to naturally emanate from the subject, while what is actually occurring is an ongoing reiteration and performance of gendered comportment that never fully achieves the gender ideal. If one fails even to approximate gender norms, one fails to be socially recognized as fully human. For Butler, discourse actually demarcates the necessary conditions for the embodiment of personhood (Butler, 171-180).
Understood as a medium, then, discourse functions as a powerful tool through which linguistic conventions social and political beliefs and practices, ideologies, subject positions, and norms can all be mediated. Yet as we have seen, discourse does not simply serve as a connecting link between a stable, exterior society and the individual. All of these social values emanate from individuals who enunciate a discourse that is at the same not completely their own, a discourse which in turn implants and reinforces the notions it contains. Discourse always consists of both input and output, and is always at once an extension of our culture and of ourselves