Altruism becomes thus the criterion of morality. There is no morality for him who lives in solitude, there is only right conduct. Morality is bound up with altruism, which on the highest scale of moral development overcomes egotism. Man feels then a moral obligation within himself to serve others in the face of human need, of hunger, thirst, loneliness, nakedness, sickness, etc. This obligation is felt in obedience to Kant’s categorical imperative. The moral feeling is a part of man’s life, it is transcendental. Morality and character are functions of the brain like memory or imagination. The essence of morality is as unexplainable by mechanical laws as the nature of life itself. The creative power that gave life to man implanted in him moral aspirations of the whole soul. The moral law is hence based upon human feeling. What the throbbing heart of the best of humanity considers right is the will of the Supreme Intelligence, and hence the moral law. Human feeling and human longing are the basis of every moral action. When it is agreed among the best men, everywhere, and in every epoch, that altruism is noble and that egotism is ignoble, then altruism is the foundation of morality. The larger the altruistic circle is, the praiseworthier it is. To benefit one’s family is laudable, but a service rendered in the interest of the community, of the nation, or of the human race, is far worthier. The highest degree of morality is hence reached in actions rendered in the interest of the race. CHAPTER XXIII SEXUAL MORALITY The racial interest is also the cause of the double standard of sex-morality of the two sexes. This is best seen by the study of the evolution of sexual morality, or the history of marriage.[DR] 1) In the first stage, the lowest conceivable stage of savagery, when men still lived in hordes, mankind lived in a state of “promiscuous” intercourse like the gregarious animals. All the males of the horde protected the females and their offspring. In the prehuman period, when horde-life was not yet known, the semi-human creatures must have lived in pairs, where every male protected his female and her offspring. Without this protection the race would have died. 2) In the second stage the irregular state was abandoned and the “consanguineous family” developed. It was founded upon intermarriage of brothers and sisters, own or collateral, in a group. Marriage between parents and children, as in the preceding stage, is now decreed immoral and is prohibited.