The strength of the fighting instinct in man has been one of the main arguments used by the militarists in support of preparation for international strife. They point to the historical fact that even among highly civilized peoples scarcely a decade passes without a kindling of the martial emotions, which explode in actual warfare. Such fighting, they say, is inevitable--the manifestation of “biological law”--and, so long as human nature remains unchanged, decision by battle must be resorted to. They urge, furthermore, that in war and in the preparations for war important physical qualities--sturdiness, hardihood, and strength for valorous deeds--are given peculiarly favorable opportunities for development, and that if these opportunities are lacking, lusty youth will give place to weaklings and mollycoddles. In addition the militarists say that war benefits mankind by its moral effects. Without war nations become effete, their ideals become tarnished, the people sink into self-indulgence, their wills weaken and soften in luxury. War, on the contrary, disciplines character, it sobers men, it teaches them to be brave and patient, it renews a true order of values, and its demand for the supreme sacrifice of life brings forth in thousands an eager response that is the crowning glory of the human spirit. As the inevitable expression of a deep-rooted instinct, therefore, and as a unique means of developing desirable physical and moral qualities, war is claimed by the militarists to be a natural necessity.[225] The militarist contention that the fighting instinct is firmly fixed in human nature receives strong confirmation in the results of our researches. Survival has been decided by the grim law of mortal conflict, and the mechanism for rendering the body more competent in conflict has been revealed in earlier chapters as extraordinarily perfect and complete. Moreover, the physiological provisions for fierce struggle are found not only in the bodies of lower animals, that must hunt and kill in order to live, but also in human beings. Since this remarkable mechanism is present, and through countless generations has served the fundamentally important purpose of giving momentous aid in the struggle for existence, the militarists might properly argue that, as with other physiological processes, bodily harmony would be promoted by its exercise. Indeed, they might account for the periodic outburst of belligerent feelings by assuming that these natural aptitudes require occasional satisfaction.[*] *[Footnote: Mr. Graham Wallas has made the interesting suggestion (The Great Society, New York, 1914, p. 66) that nervous strain and restlessness due to “baulked disposition” may result from the absence of circumstances which would call the emotional responses into action. And he cites Aristotle’s theory that pent passions may be released by represented tragedy and by music.]