But the comingling of the sexes must not degenerate in tactile eroticism, as may be observed, on any summer night, in city parks, on excursion boats, or on hotel verandas at most of our summer resorts. Of all the five senses, touch is the strongest sense, it is a sense-world in itself. Touch is the only sense that has an organ which can be doubled upon itself. The eye cannot see itself, the ear cannot hear itself, the tongue cannot taste itself, nor the nose smell itself. But the hand can pass over the body surface and both feel and be felt. It can perform the feat of being at the same time both subject and object. For this reason the sense of touch is especially adapted to be at the service of the sex-sense. The sense of sex seems to have made the sense of touch a part of its being. The sense of touch forms one of the component impulses of the sex-instinct, namely, the impulse of contrectation. Hence dalliance and caresses form a substantial part of the sex-act and are unhygienic, if not soon followed by ejaculation and orgasm. When the act has once begun, and the often observed caresses do represent the beginning, it is unhygienic and very harmful not to terminate the same. The often repeated interruption will lead to all kinds of sexual neuroses, particularly to psychic and more often to atonic impotence in men and frigidity in women. CHAPTER XX RULES OF EUGENICS The best prophylaxis against inchastity and its sequels, the contraction of venereal diseases, is the extirpation of prostitution. If the supply of the means of inchastity could be cut off, there would be no demand.[CD] A considerable part of meretricious venery could be eliminated by lifting the mist of ignorance.[CE] Armed with the proper knowledge a certain percentage of the girls who are now swelling the ranks of prostitution would surely shun this profession. But there will still remain the greater part of venal women, who, according to the best authorities, belong to the high-grade imbeciles and hence cannot be reached by instruction.[CF] This class of women who form the main part of prostitution will have to be eliminated by following strictly the rules of Eugenics. Only in this, though tedious but sure, way could defective mentality be exterminated, and prostitution thus banished from our planet within a few generations.[CG] The aim of eugenics is the production of a better humanity, especially by the elimination of bodily and mentally feeble stocks. With the discovery of the Mendelian law, eugenics was placed upon a scientific basis. The world knew by experience that desirable as well as undesirable traits are transmitted by heredity, but it thought that heredity could be controlled by environment. It believed in economic determinism. Mendel’s law revealed the inexorableness of the law of heredity.