Whenever a race is so richly endowed with the energetic material that it does not expend all its energy in the daily struggle for life, the surplus may be stored in the shape of wealth; and this stock of stored energy may be transferred from community to community, either by conquest, or by superiority in economic competition. However large may be the store of energy accumulated by conquest, a race must, sooner or later, reach the limit of its martial energy, when it must enter on the phase of economic competition. But, as the economic organism radically differs from the emotional and martial, the effect of economic competition has been, perhaps invariably, to dissipate the energy amassed by war. When surplus energy has accumulated in such bulk as to preponderate over productive energy, it becomes the controlling social force. Thenceforward, capital is autocratic, and energy vents itself through those organisms best fitted to give expression to the power of capital. In this last stage of consolidation, the economic, and, perhaps, the scientific intellect is propagated, while the imagination fades, and the emotional, the martial, and the artistic types of manhood decay. When a social velocity has been attained at which the waste of energetic material is so great that the martial and imaginative stocks fail to reproduce themselves, intensifying competition appears to generate two extreme economic types,--the usurer in his most formidable aspect, and the peasant whose nervous system is best adapted to thrive on scanty nutriment. At length a point must be reached when pressure can go no further, and then, perhaps, one of two results may follow: A stationary period may supervene, which may last until ended by war, by exhaustion, or by both combined, as seems to have been the case with the Eastern Empire; or, as in the Western, disintegration may set in, the civilized population may perish, and a reversion may take place to a primitive form of organism. The evidence, however, seems to point to the conclusion that, when a highly centralized society disintegrates, under the pressure of economic competition, it is because the energy of the race has been exhausted. Consequently, the survivors of such a community lack the power necessary for renewed concentration, and must probably remain inert until supplied with fresh energetic material by the infusion of barbarian blood. BROOKS ADAMS. Quincy, August 20, 1896. CONTENTS PAGE CHAPTER I The Romans 1 CHAPTER II The Middle Age 48 CHAPTER III The First Crusade 79 CHAPTER IV The Second Crusade 103 CHAPTER V