the Greek, the Illyrian, the Italian were all at home, and which, though based on conquest, was accepted by the conquered as the natural organisation of the civilised world. Rome had thus unique sources of strength. What sources of weakness would our observer be likely to detect behind her imposing exterior? The diminution of population is the one which has (rightly I think) most impressed historians: and it is difficult to resist the evidence, either of the fact, or of its disastrous consequences. I hesitate indeed to accept without qualification the accounts given us of the progressive decay of the native Italian stock from the days of the Gracchi to the disintegration of the Empire in the West: and when we read how the dearth of men was made good (in so far as it was made good) by the increasing inflow of slaves and adventurers from every corner of the known world, one wonders _whose_ sons they were who, for three centuries and more, so brilliantly led the van of modern European culture, as it emerged from the darkness of the early Middle Ages. Passing by such collateral issues, however, and admitting depopulation to have been both real and serious, we may well ask whether it was not the result of Roman decadence rather than its cause, the symptom of some deep-seated social malady, not its origin. We are not concerned here with the aristocracy of Rome, nor even with the people of Italy. We are concerned with the Empire. We are not concerned with a passing phase or fashion, but with a process which seems to have gone on with increasing rapidity, through good times as well as bad, till the final cataclysm. A local disease might have a local explanation, a transient one might be due to a chance coincidence. But what can we say of a disease which was apparently co-extensive with Imperial civilisation in area, and which exceeded it in duration? I find it hard to believe that either a selfish aversion to matrimony or a mystical admiration for celibacy, though at certain periods the one was common in Pagan and the other in Christian circles, were more than elements in the complex of causes by which the result was brought about. Like the plagues which devastated Europe in the second and third centuries, they must have greatly aggravated the evil, but they are hardly sufficient to account for it. Nor yet can we find an explanation of it in the discouragement, the sense of impending doom, by which men’s spirits were oppressed long before the Imperial power began visibly to wane, for this is one of the things which, if historically true, does itself most urgently require explanation.