medida de lo posible las cifras de 1909, el incremento natural de Inglaterra y Escocia, de Alemania, de Italia, de Austria y Hungría, de Bélgica, es normal; el incremento natural de Nueva Gales del Sur, de Victoria, de Australia Meridional, de Nueva Zelanda, es anormalmente alto (aunque en los países nuevos dicho incremento tal vez no sea indeseable), mientras que el incremento natural de Francia, de España y de Irlanda es anormalmente bajo. Tal método de cálculo, por supuesto, prescinde por completo de la cuestión de la deseabilidad social del proceso mediante el cual se logra el incremento normal.
Johannsen, Janus, 1905.
Rubin, "A Measure of Civilization," Journal of the Royal Statistical Society, March, 1897. "The lowest stage of civilization," he points out, "is to go forward blindly, which in this connection means to bring into the world a great number of children which must, in great proportion, sink into the grave. The next stage of civilization is to see the danger and to keep clear of it. The highest stage of civilization is to see the danger and overcome it." Europe in the past and various countries in the present illustrate the first stage; France illustrates the second stage; the third stage is that towards which we are striving to move to-day.
Baines, "The Recent Growth of Population in Western Europe," Journal of the Royal Statistical Society, diciembre de 1909.