There are different kinds of myths. This one, the myth of woman, sublimating an immutable aspect of the human condition—namely, the “division” of humanity into two classes of individuals—is a static myth. It projects into the realm of Platonic ideas a reality that is directly experienced or is conceptualized on a basis of experience; in place of fact, value, significance, knowledge, empirical law, it substitutes a transcendental idea, timeless, unchangeable, necessary. The idea is indisputable because it is beyond the given: it is endowed with absolute truth. Thus, against the dispersed, contingent, and multiple existences of actual women, mythical thought opposed the Eternal Feminine, unique and changeless. If the definition provided for this concept is contradicted by the behavior of flesh-and-blood women, it is the latter who are wrong: we are not told that Femininity is a false entity, but that the women that are concerned are not feminine. The contrary facts of experience are impotent against the myth….To pose Woman is to pose the absolute Other, without reciprocity, denying against all experience that she is a subject, a fellow human being.

…In consequence, a number of incompatible myths exist, and men tarry musing before the strange incoherencies manifested by the idea of Femininity….But if woman is depicted as the Praying Mantis, the Mandrake, the Demon, then it is most confusing to find in women also the Muse, the Goddess, Mother, Beatrice.

As group symbols and social types are generally defined by means of antonyms in pairs, ambivalence will seem to be an intrinsic quality of the Eternal Feminine. The saintly mother has for correlative the cruel stepmother, the angelic young girl has the perverse virgin: thus it will be said sometimes that Mother equals life, sometimes that Mother equals Death, that every virgin is pure spirit of flesh dedicated to the devil.

Of all these myths, one is more firmly anchored in masculine hearts than that of the feminine “mystery.” It has numerous advantages. And first of all it permits an easy explanation of all that appears inexplicable; the man who “does not understand” a woman is happy to substitute an objective resistance for a subjective deficiency of mind; instead of admitting his ignorance, he perceives the presence of a “mystery” outside himself: an alibi, indeed, that flatters laziness and vanity at once. A heart smitten with love thus avoids many disappointments: if the loved one’s behavior is capricious, her remarks stupid, then the mystery serves to excuse it all. And finally, thanks again to the mystery, that negative relation is perpetuated which seemed to Kierkegaard infinitely preferable to positive possession; in the company of a living enigma man remains alone—alone with his dreams, his hopes, his fears, his love, his vanity. This subjective game, which can go all the way from vice to mystical ecstasy, is for many a more attractive experience than an authentic relation with a human being. What foundation exists for such a profitable illusion?

From Simone de Beauvoir, The Second Sex, ch. XI: Myth and Reality