tunities afforded to migrants from the backward countries. So far as the superiority of climatic and other factors of physical environment are responsible for the physical and mental calibre of civilized peoples, it is quite evident that a rapid decline of population would be accompanied by a loss of values in the higher realms of human activity. We are not, therefore, called upon to decide whether any inherent or acquired transmissible superiority attaches to this or that civilized people. If we assumed that all were sons of Adam and that no distinct origins for primitive man were available, the long impress of certain physical environments with their cultural traditions must count so heavily as to disable us from regarding with indifference the decline of Western populations.
A not less crucial issue has arisen within the population of each country. Birth-restriction, as practised in this country, and to a less extent elsewhere, has been selection in what is held to be a wrong direction. Statistics show that the earlier exercise of birth control was confined to the better informed and more intelligent classes whose birth-rate, even when better survival conditions were taken into account, was definitely below that of the working classes. Though in recent times popular instruction has expanded the area of birth control so as to include large sections of the workers, it still remains true that the reproduction rate of the upper grades is less than that of the lower grades of the population. Here
