Louis Althusser in the context of "Marxist philosophy"

Paul-Michel Foucault (UK: /ˈfuːkoʊ/ FOO-koh, US: /fuːˈkoʊ/ foo-KOH; French: [pɔl miʃɛl fuko]; 15 October 1926 – 25 June 1984) was a French historian of ideas and philosopher, who was also an author, literary critic, political activist, and teacher. Foucault's theories primarily addressed the relationships between power versus knowledge and liberty, and he analyzed how they are used as a form of social control through multiple institutions. Though often cited as a structuralist and postmodernist, Foucault rejected these labels and sought to critique authority without limits on himself. His thought has influenced academics within a large number of contrasting areas of study, with this especially including those working in anthropology, communication studies, criminology, cultural studies, feminism, literary theory, psychology, and sociology. His efforts against homophobia and racial prejudice as well as against other ideological doctrines have also shaped research into critical theory and Marxism–Leninism alongside other topics.

Born in Poitiers, France, into an upper-middle-class family, Foucault was educated at the Lycée Henri-IV, at the École Normale Supérieure, where he developed an interest in philosophy and came under the influence of his tutors Jean Hyppolite and Louis Althusser, and at the University of Paris (Sorbonne), where he earned degrees in philosophy and psychology. After several years as a cultural diplomat abroad, he returned to France and published his first major book, The History of Madness (1961). After obtaining work between 1960 and 1966 at the University of Clermont-Ferrand, he produced The Birth of the Clinic (1963) and The Order of Things (1966), publications that displayed his increasing involvement with structuralism, from which he later distanced himself. These first three histories exemplified a historiographical technique Foucault was developing, which he called "archaeology".

Lacanianism or Lacanian psychoanalysis is a theoretical system initiated by the work of Jacques Lacan from the 1950s to the 1980s. It is a theoretical approach that attempts to explain the mind, behaviour, and culture through a structuralist and post-structuralist extension of classical psychoanalysis. Lacanian perspectives contend that the human mind is structured by the world of language, known as the Symbolic. They stress the importance of desire, which is conceived of as perpetual and impossible to satisfy. Contemporary Lacanianism is characterised by a broad range of thought and extensive debate among Lacanians.

Lacanianism has been particularly influential in post-structuralism, literary theory, and feminist theory, as well as in various branches of critical theory, including queer theory. Equally, it has been criticised by the post-structuralists Deleuze and Guattari and by various feminist theorists. Outside France, it has had limited clinical influence on psychiatry. There is a Lacanian strand in left-wing politics, including Saul Newman's and Duane Rousselle's post-anarchism, Louis Althusser's structural Marxism, and the works of Slavoj Žižek and Alain Badiou. Influential figures in Lacanianism include Slavoj Žižek, Julia Kristeva and Serge Leclaire.