only tribal.[18] The social qualities of sympathy, fidelity, and courage implied in mutual aid and defence, were no doubt acquired by man through the same means. "When two tribes of primeval man, living in the same country, came into competition, if (other circumstances being equal) the one tribe included a great number of courageous, sympathetic, and faithful members, who were always ready to warn each other of danger, to aid and defend each other, this tribe would succeed better and conquer the other.... Selfish and contentious people will not cohere, and without coherence nothing can be effected. A tribe rich in the above qualities would spread and be victorious over other tribes; but in the course of time it would, judging from all past history, be in its turn overcome by some other tribe still more highly endowed. Thus the social and moral qualities would tend slowly to advance and be diffused throughout the world." Though in a warlike state, where courage is especially necessary to tribal existence, the bravest men would perish in larger numbers than other men, and the survival of the unfittest would seem thus to be secured, the influence of their bravery on others might excite the latter to imitation and do far more good than the begetting of offspring who would inherit their bravery. So, also, pity, though inciting modern society to the preservation of the weak, yet is useful in that it cultivates sympathy; and so, too, wealth, affording leisure for intellectual pursuits and a wider choice in marriage, tends, in the end, to the preservation of the fittest morally, by direct or indirect means.[19] Altruistic action, followed from selfish motives, may become habit; habits of benevolence certainly strengthen the feeling of sympathy; and "habits followed during many generations probably tend to be inherited." Furthermore, melancholy tends often to suicide, as violence, and quarrelsomeness to a bloody end, intemperance to the destruction of individual life, and profligacy to disease and sterility; so that some elimination of the worst dispositions takes place. These are some of the probable steps of advancement, though the process is too complex to be clearly followed out. The approbation of others--the strengthening of sympathies by habit--example and imitation--reason--experience and even self-interest--instruction during youth, and religious feelings--are the causes which lead to the advancement of morality.[20] In the paragraph just quoted, Darwin says: "With civilized nations, as far as an advanced standard of morality and an increased number of fairly good men are concerned, natural selection apparently effects but little, though the fundamental social instincts were originally thus gained"; but he later writes: "Judging from all that we know of man and the lower animals, there has always been sufficient variability in their intellectual and moral faculties for a steady advance through natural selection"; and he further says: "No