To these principles common to all organic nature must be added another which is almost peculiar to man alone. We often hear that environment is the determinant of the nature of both animals and man. But the distinctive quality of man is the subjection of the environment to the ruling faculty; man is not necessarily conditioned by his environment, but a direct measure of his civilisation is the extent to which he creates his own conditions. Other communal animals, as the ant, the bee, or the beaver, have anticipated this to some extent; but in man alone can the ruling faculty rise to an entire reversal of almost every condition of environment. The mental equivalents of these physical modifications are obviously true in common experience and in historical example. (1) That a favourable variation of mind gives a determining advantage needs no illustration, as every sharp and able man of business has shown this in all ages. (2) That mental qualities are inherited has been pretty generally recognised, and the work of Galton on Hereditary Genius has enforced this by statistical example. But the historical consequences have not been sufficiently noticed; for it is obviously possible by selective action to increase or diminish not only the bodily activity but also the mental ability seen in the whole community. The series of proscriptions of all the leading men of Rome, alternately on one side and then on the other, from Marius down to Octavius, was so disastrous a drain of political ability, that only the Julian family was left; and there was never an able emperor of Roman ancestry after that line was extinct. The expulsion of the Huguenots from France drained it of the active middle class minds, and left the great gap in the continuity of sympathy which made the Revolution possible. The later expulsion or extermination also of the active upper class minds drained that land of nearly all the hereditary ability of the race: the consequence has been to leave at the present day a nation of mediocrities, among whom there is but a fraction of the genius seen in Germany and England on either side of it. Almost every leading name is that of a foreigner, as for instance Waddington, Zurlinden, Eiffel, Reinach, Rothschild, Gambetta, Maspero. Another very important consideration is that sporadic ability is not inherited in the same manner as long continued family ability. Not a single Roman Emperor who rose solely from his individual powers left a worthy and capable son. The Gordians were a good senatorial family, and ran through three generations on the throne. In England the same thing is seen. The main source of new men of ability is from sturdy Puritan or Quaker stocks that have long practised self-denial and hard work; old families with long traditions of public service continue usually on the same line of ability; but the _nouveaux riches_ who have sprung forward on some lucky speculation or trade enterprise