Thus it is that affluence, in the long run, itself imposes a check on reproduction. Prosperity, under the stress of the urban conditions with which it tends to be associated, has been transformed into that calculated forethought, that deliberate self-restraint for the attainment of ever more manifold ends, which in its outcome we term "civilization."
It is frequently assumed, as we have seen, that the process by which civilization is thus evolved is a selfish and immoral process. To procreate large families, it is said, is unselfish and moral, as well as a patriotic, even a religious duty. This assumption, we now find, is a little too hasty and is even the reverse of the truth; it is necessary to take into consideration the totality of the social phenomena accompanying a high birth-rate, more especially under the conditions of town life. A community in which children are born rapidly is necessarily in an unstable position; it is growing so quickly that there is insufficient time for the conditions of life to be equalized. The state of ill-adjustment is chronic; the pressure is lifted from