Page:Little Essays of Love and Virtue (1922).djvu/179

 tion, even at a fairly advanced stage, nations tend to break out over their frontiers with resulting war; but the period when they reach “the plenitude of vigour and self-consciousness” is exactly the period when the birth-rate begins to decline, and the population, deliberately or instinctively, controls its own increase. That has, for instance, been the history of France since the great expansion of population, roughly associated with the Napoleonic epopee,—which doubtless covered a web of causes, sanitary, political, industrial, favourable to a real numerical increase of the nation—had died down slowly to the level we witness to-day. Similarly, with regard to the opposing school, we must undoubtedly accept a natural fall in the birth-rate with a rising civilisation; that has always been visible in highly civilised individual couples, and it is an easily ascertainable zoological fact that throughout the evolution of life procreativeness has decreased with the increased development of species. We may agree that a natural factor comes into the recent fall in the human birth-rate. But to argue that because a natural decline in birth-rate is the essential factor in the slowing down of procreative