An impulse, to one who does not share it actually or imaginatively, will always seem to be mad. All impulse is essentially blind, in the sense that it does not spring from any prevision of consequences. The man who does not share the impulse will form a different estimate as to what the consequences will be, and as to whether those that must ensue are desirable. This difference of opinion will seem to be ethical or intellectual, whereas its real basis is a difference of impulse. No genuine agreement will be reached, in such a case, so long as the difference of impulse persists. In all men who have any vigorous life, there are strong impulses such as may seem utterly unreasonable to others. Blind impulses sometimes lead to destruction and death, but at other times they lead to the best things the world contains. Blind impulse is the source of war, but it is also the source of science, and art, and love. It is not the weakening of impulse that is to be desired, but the direction of impulse towards life and growth rather than towards death and decay. The complete control of impulse by will, which is sometimes preached by moralists, and often enforced by economic necessity, is not really desirable. A life governed by purposes and desires, to the exclusion of impulse, is a tiring life; it exhausts vitality, and leaves a man, in the end, indifferent to the very purposes which he has been trying to achieve. When a whole nation lives in this way, the whole nation tends to become feeble, without enough grasp to recognize and overcome the obstacles to its desires. Industrialism and organization are constantly forcing civilized nations to live more and more by purpose rather than impulse. In the long run such a mode of existence, if it does not dry up the springs of life, produces new impulses, not of the kind which the will has been in the habit of controlling or of which thought is conscious. These new impulses are apt to be worse in their effects than those that have been checked. Excessive discipline, especially when it is imposed from without, often issues in impulses of cruelty and destruction; this is one reason why militarism has a bad effect on national character. Either lack of vitality, or impulses which are oppressive and against life, will almost always result if the spontaneous impulses are not able to find an outlet. A man’s impulses are not fixed from the beginning by his native disposition: within certain wide limits, they are profoundly modified by his circumstances and his way of life. The nature of these modifications ought to be studied, and the results of such study ought to be taken account of in judging the good or harm that is done by political and social institutions.