Sexual Politics by Kate Millett is considered a classic work in critical feminist and gender studies (and, to some extent, in Marxist studies). The book is a critical example of what is known as "second-wave feminism," which arose in the mid-twentieth century—following the "first wave" of women's suffrage—out of persistent gender inequalities that endured despite political reforms. Millett's work applies feminist theory to aspects of personal lives, social structures, and power dynamics, and examines how patriarchal thought has permeated areas like economics and ethics.

While patriarchy as an institution is a social constant so deeply entrenched as to run through all other political, social, or economic forms, whether of caste or class, feudality or bureaucracy, just as it pervades all major religions, it also exhibits great variety in history and locale.

In this quote, Millett discusses the near-universal presence of the patriarchy, which is a central theme to her book. In simple terms, a patriarchy refers to a system or society that is ultimately controlled by men. However, by extension, it logically follows from this structure that women are suppressed and denied positions of power (literal or figurative). A patriarchy, however, must be understood not just as a model that applies to the structures of government and institutions in a society but also as a social hegemony that influences perception of gender roles and performance. Millett points out that, while men may dominate positions of power (as a clear and evident illustration of patriarchy), this power system is self-perpetuating, as the men in power thus dictate male-centric policies which normalize the perception of patriarchy as something that is natural and inevitable.

Most patriarchies go to great length to exclude love as a basis of mate selection. Modern patriarchies tend to do so through class, ethnic, and religious factors. Western classical thought was prone to see in heterosexual love either a fatal stroke of ill luck bound to end in tragedy, or a contemptible and brutish consorting with inferiors. Medieval opinion was firm in its conviction that love was sinful if sexual, and sex sinful if loving.

In this passage, Millett explores the idea of sexual and romantic relationships and how a patriarchy might discourage love and affection in the process of forming these relationships. For instance, medieval marriages were arranged to accrue political power (in the cases of princes and dukes) or for economic reasons. Historically, a marriage was considered to be the transfer of property—that is, a woman—from one owner to another (her father to her husband); a woman was traded in the hopes of producing heirs to perpetuate her husband's familial legacy.

In Millett's view, despite the fact that this is no longer considered to be the sole purpose of marriage, the legacy of treating women as commodities persists—as their primary worth as a wife is situated in their ability to produce children and be caregivers, and not in their genuine affection for their husbands.

Patriarchal marriage and the family with its ranks and division of labor play a large part in enforcing them.

To Millett, the patriarchy reinforces itself through all power structures and relations. She argues that, when marriage is considered to be something that is irrevocable, then it endows the husband (i.e., the partner with power) the ability to treat his wife horribly—as escape from the union is actively discouraged or even explicitly prevented. Millett argues that the traditional division of labor in a marriage, in which the wife is relegated to the domestic sphere while the husband bears the financial responsibilities, limits the capabilities of the wife to have a "life of her own," so to speak.

Millett, and most feminist critics, commonly argue that an equal marriage would consist of a division of labor that affords both parties the ability to take equal parts in child rearing and financial support. In this way, a woman is no longer subject to patriarchal constraints that require her to remain bound to the domestic sphere and encourage her to sacrifice her own identity for the sake of her children and husband.