Mill uses a universality motif in various ways, referring to the “universal opinion” (3), “universal custom” (23), “universal interest” (36), etc. This term implies that everyone everywhere has agreed on a particular custom or idea—for example, that women are passive while men are active. However, as Mill points out, these ideas are often based on assumptions or habits that require further investigation, and so they should not be taken as fact without scrutiny. The motif thus develops the theme of Nature Versus Society and the Gender Hierarchy: Much of what is “universal” is widespread not because it reflects an eternal truth of human nature but simply because it has been effectively promulgated throughout society, often by those with a vested interest in doing so (e.g., men).

While the phrase “a priori” appears only once in The Subjection of Women—“The à [sic] priori presumption is in favour of freedom and impartiality” (3)—it is nonetheless an underlying motif throughout the work. The Latin “a priori” translates to “from the former” and refers to knowledge learned from deduction rather than experience, or “a posteriori.” Mill uses this concept to emphasize how a modern society should begin from a position of egalitarianism: When there are laws to impede a person’s freedom, the burden of proving why such a restraint is necessary must be provided.