Until there is adequate development in the child of the cortical center of sexual emotion, and while the latter is as yet incapable of sexual differentiation, all external impressions remain destitute of mental meaning; sexual neutrality being destroyed, not through differences of dress, habits, manners, voice, form or occupation, nor even by the growing intensity of sexual desire, but by the intelligence which directs the latter into normal and natural channels.

And, hand in hand with this physical development, marches the psychical ; the rudimentary instinct adapting itself, gradually and naturally, but not without serious danger sometimes of accidental deflection, to those forms and ideas of sex which constitute its subsequent standard. If the original constitution be favorable to normal development, a healthful and harmonious psychosexual organism will result; but if there exist any of those unfavorable hereditary tendencies, which are far easier to talk about than to properly analyze, if environment, education, vicious surroundings, or inverted habits of thought, exert a counter influence, or if there be any anomaly of the central conditions, perversity may supervene, and a contrary sexual feeling manifest itself.