The prolonged slavery of women is the darkest page in human history.

Stanton frames women’s long subordination not as a private misfortune or a natural condition, but as a central moral catastrophe of civilization—“the darkest page” in the human record. By calling it “slavery,” she deliberately links women’s legal and social dependence (lack of political rights, constrained property and marital rights, enforced domestic roles) to a system of domination maintained by law, custom, and religion. The superlative language is rhetorical: it aims to shock readers into recognizing the scale and duration of gender oppression and to justify urgent reform. The line also reflects a core feminist argument of her era: that progress and justice cannot be claimed while half of humanity remains structurally unfree.