Every individual being has to pass through all the grades of the evolution of animal life. The remote ancestors of the human race were bisexual. The same bisexuality exists in the embryo, represented by the Wolffian and Müllarian ducts or the bisexual “Anlage.” Later in the development, there arises, so to say, a struggle between the male and female elements. When one element has been conquered a monosexual being evolves whose mental inclinations correspond with the sexual glands. The basis for the yearnings and longings of one sex for the other would thus be the desire for perfection, for the completion of those sides of our being which are present in the bisexual “Anlage” or the “ground-work” of sex, but failed in development, and for this reason can not be brought to a realization of ourselves. It is, as if in the accord of our being some tones are kept in suspension and are only allowed to chime in with the tones of the other half. Then, and then only, there is a perfect harmony. Sometimes, however, functional retrogression or atavistic recurrence into the earlier hermaphroditic forms of the animal kingdom may take place, or traces of the conquered sexuality, at least so far as the mental characteristics are concerned, may remain; and it is these that provoke the manifestations of inverted sexuality. Individuals, thus affected, have a sexually abnormal instinct which is out of harmony with the physical sex and its rôle in the function of procreation. The man thus organized feels utter indifference to women, and conversely the woman to men, but they have a strong preference and pronounced sexual inclination toward their own sex. The man easily understands why a woman should love a man but he can not understand how a man could love a woman. The same is the case with the homosexual woman. She is at a loss to understand how a woman could love a man. The anomaly of homosexuality is as old as history and was, in fact, oftener found among the ancients than it is nowadays. Plato, in his Banquet, tries to explain the enigmatical manifestation of homosexuality in men in the following poetical way: There is an Aphrodite without an Eros, but there are two goddesses of that name. The older Aphrodite, being the daughter of Uranos, and thus called Urania, came into being without a mother. The younger Aphrodite is the daughter of Zeus and Artemis and is called Pandemonia. The Eros of the former is Eros Uranos, of the latter is Eros Pandemos. Eros Uranos did not choose a female, but a male, as his companion. Hence, whoever is inspired with the love of this deity turns to the male sex. This Platonic explanation takes no notice of the existence of Lesbian love. His explanation of Lesbianism would have been that Aphrodite Urania did not choose a male but a female as her companion, and the woman inspired with the love of this deity turns to the female sex or Lesbian love. Lesbianism was as much in vogue in Greece in the days of Plato as paederastia.[BC]