The total abolition of war would, of course, be the ideal, but there is no possibility of this in the near future. The fighting instinct, it must be remembered, is one of the most primitive and powerful that the human mechanism contains. It was evolved in great intensity, to give man supremacy over his environment--for the great "struggle for existence" is with the environment, not with members of one's own species. Man long ago conquered the environment so successfully that he has never since had to exert himself in physical combat in this direction; but the fighting instinct remained and could not be baulked without causing uneasiness. Spurred on by a complex set of psychological and economic stimuli, man took to fighting his own kind, to a degree that no other species shows. Now contrary to what the militarist philosophers affirm, this particular sort of "struggle for existence" is not a necessity to the further progressive evolution of the race. On the contrary it more frequently reverses evolution and makes the race go backward, rather than forward. The struggle for existence which makes the race progress is principally that of the species with its environment, not that of some members of the species with others. If the latter struggle could be supplanted by the former then racial evolution would go ahead steadily without the continuous reversals that warfare now gives. William James saw, we believe, the true solution of the problem of militarism, when he wrote his famous essay on _The Moral Equivalent of War_. Here is man, full of fighting instinct which will not be baulked. What is he to do? Professor James suggested that the youth of the nation be conscripted to fight the environment, thus getting the fight "out of its system" and rendering a real service to the race by constructive reclamation work, instead of slaying each other and thus turning the hands of the evolutionary clock backward. When education has given everyone the evolutionary and eugenic view of man as a species adapted to his environment, it may be possible to work out some such solution as this of James. The only immediate course of action open seems to be to seek, if possible, to diminish the frequency of war by subduing nations which start wars and, by the organization of a League to Enforce Peace; to avoid war-provoking conquests; to diminish as much as possible the disastrous effects of war when it does come, and to work for the progress of science and the diffusion of knowledge which will eventually make possible the greater step, effective international organization. CHAPTER XVII GENEALOGY AND EUGENICS Scientific plant breeders to-day have learned that their success often depends on the care with which they study the genealogy of their plants. Live-stock breeders admit that their profession is on a sure scientific basis only to the extent that the genealogy of the animals used is known.