Discourse Andrew Law Newcastle University, UK The term “discourse” is very much dependent upon “the disciplinary context in which the term occurs” (Mills 1997, 3). Mills explains how the “term ‘discourse’ has become common currency in a variety of disciplines [including]: critical theory, sociology, linguistics, philosophy, social psychology and many other felds, so much so that it is frequently left undefned, as if its usage were simply common knowledge” (Mills 1997, 1). While the term “discourse” is ubiquitous, it can be argued that the academic signifer and signifed have a specifc history that has developed through a large number of (sometimes interlocking) theoretical disciplines. Four schools are salient to the discipline of human geography: (i) a critical theory school; (ii) a neo-Foucauldian school (or what we might call a practice and performativity school); (iii) a critical linguistic school; and (iv) a discursive psychology (or reifcation) school. The critical theory school In the feld of critical theory, studies of discourse are often related to what Jørgensen and Phillips have described as “critical research … [which] investigate[s] and analyse[s] power relations in society” and which “formulate[s] normative per- spectives from which a critique of such relations can be made with an eye on the possibilities for social change” (Jørgensen and Phillips 2002, 2). The International Encyclopedia of Geography. Edited by Douglas Richardson, Noel Castree, Michael F. Goodchild, Audrey Kobayashi, Weidong Liu, and Richard A. Marston. © 2017 John Wiley & Sons, Ltd. Published 2017 by John Wiley & Sons, Ltd. DOI: 10.1002/9781118786352.wbieg0552 As a starting place it can be argued that theories of discourse in this tradition actually owe their beginnings to neo-Marxist reinterpretations of the concept of ideology. The work of the French neo-Marxist Louis Althusser (1918–1990) and his discussion of ideology has had an impact on a range of critical theories of discourse. Althusser suggests that ideology in a capitalist society is produced through the state and its institutions: what Althusser called ideological state apparatus (ISAs). Althusser also suggests that “ideology works through constituting (‘interpellating’) persons as social subjects, fxing them in subject positions, while at the same time giving them the illusion of being free agents” (Fairclough 1994/1992, 30). Without a doubt, these early ideas of ideology had a major impact on a range of poststructuralist thinkers who developed new theories of power, discourse, and identity. One major commentator infuenced by Althusser’s ideas was the French poststructuralist philosopher Michel Foucault (1926–1984). As opposed to viewing power as emerging from a singular source, Foucault argued that power is dispersed and is tied up with institutions. For Foucault, institutions refer to historical blocks of knowledge or epistemes. Foucault contends that an episteme is a system of knowledge or more appropriately a site (or framework) of discursive production. In short, epistemes, or discursive frameworks, defne what can be understood as knowledge in a particu- lar time period. Moreover, epistemes produce multiple discourses (as opposed to ideologies) that cannot be read as sites or conduits of bour- geois hegemony, but are sites of production and reduction. Thus, Foucault contends that power is not only a weighty force – it is not only a force