While modesty, for example, during childhood, is essentially but an uncomprehended and incomprehensible exaction of education and imitation, and in the innocence and _näiveté_ of the child but imperfectly expressed; in the youth and maiden it becomes an imperative requirement of self-respect; and, if in any way it is offended, intense vasomotor reaction (blushing) and psychical emotion are induced. If the original constitution is favorable and normal, and factors injurious to the psycho-sexual development exercise no influence, then a psycho-sexual personality is developed that is so unchangeable, and corresponds so completely and harmoniously with the sex the individual represents, that subsequent loss of the generative organs (as by castration), or the climacteric or senility, cannot essentially alter it. But this, of course, is not to declare that the castrated man or woman, the youth and the aged man, the maiden and matron, the impotent and the potent man, do not differ essentially from one another mentally. An interesting and important question for what follows is, whether the peripheral influences of the generative glands (testes and ovaries), or central cerebral conditions, are the determining factors in psycho-sexual development. The fact that congenital deficiency of the generative glands, or removal of them before puberty, has a great influence on physical and psycho-sexual development, so that the latter is distorted and assumes a type more closely resembling the opposite sex (eunuchs, certain viragoes, etc.), betokens their great importance in this respect. But that the physical processes taking place in the genital organs are only co-operative, and not the exclusive factors in the process of development of the psycho-sexual character, is shown by the fact that, notwithstanding a normal anatomical and physiological state of these organs, a sexual instinct may be developed which is the exact opposite of that characteristic of the sex to which the individual belongs.