It offers an accessible historical overview of the emergence of the prescription of the principle of equality between men and women as a language act of the dominant Western discourse. In order to address the resulting "in-difference", it starts from solid Freudolacanian foundations to carry out a systematized reading of this speech act, in search of consequences for culture and the subject. He goes on to clarify the logical underpinnings that make explicit the relationship between the prescription of the principle of equality with parallel sociocultural phenomena, as well as with paradoxes that cross the current social pact through circuits such as inclusion-exclusion, instituted-instituting, reprobation-idealization. It takes advantage of psychoanalysis as a method and as a theory, which in its time made it possible to think sexuation as a symbolic attribute in the human species, but also sexual difference as a signifying difference, matrix of language as its specific and privative habitat, a paradox usually eluded in defense of ideological positions opposed to the gender approach. It can enable fruitful dialogues with other disciplines: philosophy, linguistics, law, sociology, pedagogy.