We have been God-like in our planned breeding of our domestic plants and animals but rabbit-like in our unplanned breeding of ourselves.
The history of almost every civilization furnishes examples of geographical expansion coinciding with deterioration in quality.
Civilization is a movement - not a condition a voyage - not a harbour.
We are in the first age since the dawn of civilization in which people have dared to think it practicable to make the benefits of civilization available to the whole human race.