third, between the several tribes and nations that succeeded Rome. There has been no rest in Europe, no isolation. War has gone on almost unceasingly, between lord and lord, tribe and tribe, nation and nation; and civilization has kept pace with it, developing with a rapidity in marked contrast with the stagnation of China during the same period.
The difference is a striking one. That war was its cause, it is true, may be open to question. Race distinctions may have had much to do with it; but these are certainly insufficient to explain the greatness of the difference, particularly when we remember that during the warlike and advancing period of China the Aryans of Europe were, so far as we are aware, in a state of tribal isolation and stagnation, with no hostilities other than intertribal quarrels. How long they had remained in this condition no one can tell. They broke out of it only when their period of migration and of warlike relations with foreign peoples began, and from that time forward they have steadily advanced from barbarism to high civilization.
If we ask what is the philosophy of this, the answer may not be difficult to reach. Unlike the fixed conservatism of peace, war introduces new conditions, new foundations for human thought, on which the edifice of future civilization may be erected; and, breaking up the isolation of peace, it spreads these conditions throughout the world, making distant nations participants in their influences. The progress of mankind means simply the development of the human mind. Ideas are the seeds of civilization, and under whatever form it appears the idea must be born first, the embodiment must come afterward. In seeking for the causes of advancement, then, we must seek for the sources of new ideas; but, as experience lies at the root of ideas, new ideas can only arise from new experiences. Whence, then, do we derive our experiences? No isolated individual can learn much of himself. His own powers of observation and thought are limited. Our minds can only rapidly develop when we avail ourselves of the experience of others. In this way only can they become storehouses of new thoughts. There is a common stock of such thought abroad in the world, from which we derive the great mass of the ideas which we call our own. And, obviously, that mind will be most developed which comes into contact with and assimilates the greatest number of these thoughts.
The same holds good with nations. An isolated nation is in the same position as an isolated individual. Its experiences are limited, its ideas few and narrow in range. Its thoughts move in one fixed channel, and the other powers of its mind are apt to become virtually aborted. An isolated nation, then, is not likely rapidly to gain new ideas. Yet peace, in all barbarian and semi--
