The best fit to produce the best offspring are ceasing to produce their kind, while the fertility of the worst remains undisturbed.

The most striking demographical phenomenon of recent years is the declining birth-rate of civilised nations.

In Germany the birth-rate has fallen from 40 to 35 per thousand of the population; in England from 35 to 30; in Ireland from 26 to 22; in France from 26 to 21; and in the United States from 36 to 30 during the last twenty years; while, in New Zealand, it has declined from 40.8, in 1880, to 25.6, in 1900.

In Australia there were 47,000 less births in 1899 than would have occurred under the rates prevailing ten years ago.
There is a consensus of opinion among demographists that this decline is due to the voluntary curtailment of the family in married life.

Prudence is the motive, and self-restraint the means by which this curtailment is made possible.