His writings have had an enormous impact on other scholarly work: Foucault's influence extends across the humanities and social sciences, and across many applied and professional areas of study.
He’s well known for his critiques of various social institutions, most notably psychiatry, medicine and the prison system, and also for his ideas on the history of sexuality.
His general theories concerning power and the relation between power and knowledge, as well as his ideas concerning "discourse" in relation to the
history of Western thought have been widely discussed and applied.
Foucault was also opposed to all social constructs that implied an identity, which included everything from the identity of male/female and homosexuality, to that of criminals and political activists.
His work is often described as postmodernist or post-structuralist by contemporary commentators and critics.
During the 1960s, however, he was more often associated with the structuralist movement.
Although he was initially happy to go along with this description, he later emphasized his distance from the structuralist approach, arguing that unlike the structuralists he did not adopt a formalist approach.
Neither was he interested in having the postmodern label applied to his own work, saying he preferred to discuss how 'modernity' was defined.
While each of them takes issue with different aspects of Foucault's work, all of these approaches share the same basic orientation:
Foucault seems to reject the liberal values and philosophy associated with the Enlightenment while simultaneously secretly relying on them.
They argue that this failure either makes him dangerously nihilistic, or that he cannot be taken seriously in his disavowal of normative values and in fact his work ultimately presupposes them.
Some historians as well as others have also criticized Foucault for his use of historical information, claiming that he frequently misrepresented things, got his facts wrong, or simply made them up entirely.
Perhaps the most notable of these was Jacques Derrida's extensive critique of Foucault's reading of Rene Descartes' Meditations on First Philosophy.
Derrida's criticism led to a break in their friendship and marked the beginning of a fifteen year-long feud between the two.
It is important to note that there has been considerable debate over both these sets of criticisms and they are not universally accepted as valid by all critics.
on a number of occasions Foucault took issue with the first kind of criticism noting that he believed strongly in human freedom and that his philosophy was a fundamentally optimistic one, as he believed that something positive could always be done no matter how bleak the situation.
In relation to the second criticism, Foucault on a number of occasions refuted charges of historical inaccuracy particularly in relation to Madness and Civilization.
The History of Sexuality
Three volumes of The History of Sexuality were published before Foucault's death in 1984.
The first and most referenced volume, The Will to Knowledge translated in 1977, focusing primarily on the last two centuries, and the functioning of sexuality as a regime of power and related to the emergence of biopower.
In this volume he attacks the "repressive hypothesis," the very widespread belief that we have, particularly since the 19th century, "repressed" our natural sexual drives.
The History of Sexuality
The second two volumes, The Use of Pleasure and The Care of the Self dealt with the role of sex in Greek and Roman antiquity.
Both were published in 1984, the year of Foucault's death, with the second volume being translated in 1985, and the third in 1986. A fourth volume, dealing with the Christian era, was almost complete at the time of Foucault's death, but there is as yet no indication that it will be published.
Basic Tenets of Power
The operation of power cannot be separated from the treatment of knowledge and discourse.
Forms of domination are built into the very understanding of the common activity or goods sought or whatever forms of the substance of a relationship.
All individuals exercise, and are subjected to power through a net-like organization.
Power requires the abandonment of the legal view that defines power as the enforcement of the law.