If a Black Death could be spread throughout the world once in every generation survivors could procreate freely without making the world too full.
Bertrand RussellThe human animal, like others, is adapted to a certain amount of struggle for life [and] the mere absence of effort from his life removes an essential ingredient of happiness. [. . .] He forgets that to be without some of the things you want is an indispensable part of happiness.
Bertrand Russell