Foucault argues that we generally read the history of sexuality since the 18th century in terms of what Foucault calls the "repressive hypothesis." The repressive hypothesis supposes that since the rise of the bourgeoisie, any expenditure of energy on purely pleasurable activities has been frowned upon. As a result, sex has been treated as a private, practical affair that only properly takes place between a husband and a wife. Sex outside these confines is not simply prohibited, but repressed. That is, there is not simply an effort to prevent extra-marital sex, but also an effort to make it unspeakable and unthinkable. Discourse on sexuality is confined to marriage.
The repressive hypothesis explains that there have been certain outlets of confession, where "improper" sexual feelings could be released safely. Foucault identifies prostitution and psychiatry as two such outlets. Steven Marcus labels those who turned to psychiatrists or prostitutes in the Victorian era as the "other Victorians." These "other Victorians" created their own space for discourse on sexuality that freed them from the confines of conventional morality.
The 20th century is no different, according to the repressive hypothesis. Freud may seem to have made open and frank discussions of sexuality possible, but this discourse is still confined to the academic and confessional realm of psychiatry. We cannot free ourselves from this repression simply by means of theory: we must learn to be more open about our sexuality, to talk about it, to enjoy it. Discourse on sexuality, seen as a revolt against a repressive system, becomes a matter of political liberation rather than intellectual analysis.
Foucault suggests the repressive hypothesis is essentially an attempt to give revolutionary importance to discourse on sexuality. The repressive hypothesis makes it seem both defiant and of utmost importance to our personal liberation that we talk openly about sex. Our discourse on sexuality, in its promise for a better, freer way of life, is a form of preaching.
Foucault wishes to address the modern paradox of our discourse on sexuality: why do we proclaim so loudly that we are repressed, why do we talk so much about how we can't talk about sex? A supporter of the repressive hypothesis might answer that we are so aware of our repression because it is so evident, and liberating ourselves is a long process that can only be advanced by open, frank discussion.
Foucault asks three questions about the repressive hypothesis: (1) Is it historically accurate to trace what we think of today as sexual repression to the rise of the bourgeoisie in the 17th century? (2) Is power in our society really expressed primarily in terms of repression? (3) Is our modern- day discourse on sexuality really a break with this older history of repression, or is it part of the same history?
In questioning the repressive hypothesis, Foucault is not primarily interested in contradicting it, and he certainly does not want to deny the fact that, for instance, sex has been a taboo subject in Western culture. His interest is primarily the "discursive fact" of sexuality: he wants to know how and why sexuality is made an object of discussion. Ultimately, his interest is not in sexuality itself, but in our drive for a certain kind of knowledge, a certain perspective, and the kind of power we find in that knowledge.
Foucault uses the word "discourse" frequently, and has a very specific meaning in mind. When we talk about a "discussion," we are talking only about what has been said. When we talk about a "discourse," we are talking also about who has done the speaking, how they have done it, in what context, in reaction to what, and so on. The term "discourse" takes in the wider context in which words are uttered.
Discourse is important to Foucault because to him, language and knowledge are closely linked to power. Speech and writing are not simply the communication of facts that occurs in a vacuum. As important as what is said is who decides what is said. Foucault develops a complex body of thought out of the old saying that "knowledge is power." Whoever determines what can be talked about also determines what can be known. Whoever determines what can be known effectively determines how we think and who we are. According to Foucault, then, language and knowledge always have a political edge.
According to the repressive hypothesis power has been exercised to repress discussion of sex. More important than sex, though, is the discourse on sexuality. The institution of marriage has claimed the discourse on sexuality as its exclusive property: it has complete power of what is and is not said about sexuality. Effectively, culture bans any discourse on sexuality that occurs outside the confines of marriage.
The repressive hypothesis explains why the institution of marriage claims exclusive rights to discourse on sexuality. This hypothesis links sexual repression to the rise of the bourgeoisie. Unlike the aristocracy that preceded it, the bourgeoisie became rich through work and industriousness. Such a class would value a stern work ethic, and would frown upon wasting energy on frivolous pursuits. Sex for pleasure, then, became an object of disapproval, as an unproductive waste of energy.
Discourse, power, and knowledge are all linked in this hypothesis. On the one hand, those who are in power, the bourgeoisie, control discourse. They decide how sex can be spoken about, and by whom, and so they control also the kind of knowledge we have regarding sex. On the other hand, this control over discourse is closely linked to their maintenance of power. The bourgeois would want to control and confine sex because it is a dangerous opponent to their work ethic. The desire to control discourse and knowledge about sex is essentially a desire to control power.
The repressive hypothesis gives a clear account of how sex has been regarded since the 18th century: it explains how discourse on sexuality has been controlled and confined, and how that has been in the interests of the bourgeoisie. Foucault, however, is not satisfied with this hypothesis, and this book stands as a compelling attack on it. However, his attack does not simply consist of saying the hypothesis is wrong and taking a contrary position. Rather, it consists of taking a step back, and seeing where this hypothesis comes from, and why.
Foucault recognizes the repressive hypothesis itself as a form of discourse. We have developed a whole framework in which to talk about the ways in which bourgeois society represses our sexual impulses. We have developed a way of talking about how we are prevented from talking about sex. We have come to talk about our need to break free from this repression, to talk freely about sex and to enjoy sex, as a part of a larger political rebellion against bourgeois society.
Just like any other form of discourse, the repressive hypothesis is not simply a set of facts in a vacuum. It forces a Marxist reading of history: one where sexual repression is part of a larger history of class struggle. More important to Foucault than whether or not the repressive hypothesis is true is how the repressive hypothesis is formulated and why. Why is it so important to us to talk about sex, why do we have to insist that we are rebelling in doing so, and why do we insist on seeing that rebellion as part of a larger, political rebellion? Foucault sees this discourse as just a surface manifestation of a deeper will, a will to a certain kind of knowledge and a certain kind of power. His investigation wants to dig beneath the hypothesis itself and find what motivates it.