Throughout the history of thought we find that the prevailing philosophies have always reflected some of the characteristics of their time. For instance, in those periods when, as historians tell us, the tendency towards unity, conformity, system, order, and authority was strong, we find philosophy reflecting these conditions by emphasizing the unity of the universe; while in those periods in which established order, system, and authority were disturbed, the philosophy of the time emphasizes the idea of multiplicity as opposed to the unity of the universe, laying stress on freedom, creative action, spontaneity of effort, and the reality of change. There can be little doubt that this is the chief reason why Bergson's philosophy has found such an amount of acceptance in a comparatively short period. The response to his thought may be explained very largely by this, that already his fundamental ideas existed, although implicit, unexpressed, in the minds of a great multitude of thoughtful people, to whom the static conceptions of the universe were inadequate and false. We must not, on the other hand, overlook the fact that Bergson's statements have in their turn given an emphasis to all aspects of thought which take account of the reality of change and which realize its importance in all spheres. A writer on world politics very aptly reminds us that "life is change, and a League of Peace that aimed at preserving peace by forbidding change would be a tyranny as oppressive as any Napoleonic dictatorship. These problems called for periodic change. The peril of our future is that, while the need for change is instinctively grasped by some peoples as the fundamental fact of world-politics, to perceive it costs others a difficult effort of thought." [Footnote: H. N. Brailsford on Peace and Change, Chap. 3 of his Book A League of Nations.] However difficult it may be for some individuals and for some nations to grasp it, the great fact is there--the reality of change is undeniable.