All over the world till lately, and in most of the world still today, mankind has been following the course of nature, that is to say, it has been breeding up to the maximum. To let nature, take her extravagant course in the reproduction of the human race may have made sense in an age in which we were letting her take her course in decimating mankind by the casualties of war, pestilence and famine.
Being human, we have at last revolted against that senseless waste. We have started to impose on nature's heartless play a humane new order of our own. But. once man has begun to interfere with nature, he cannot afford to stop half way. We cannot with impunity cut down the death-rate and at the same time allow the birth-rate to go on taking nature's course. We. must consciously try to establish an equilibrium or sooner or later, famine will stack abroad again.