What a man knows is everywhere at war with what he wants.

Technology made large populations possible; large populations now make technology indispensable.

There are some optimists who search eagerly for the skunk cabbage which in February sometimes pushes itself up through the ice, and who call it a sign of spring. I wish that I could feel that way about it, but I do not. The truth of the matter, to me, is simply that skunk cabbage blooms in the winter time.

Both the cockroach and the bird would get along very well without us, although the cockroach would miss us most.

If only the fit survive and if the fitter they are the longer they survive, then Volvox must have demonstrated its superb fitness more conclusively than any higher animal ever has.

The rare moment is not the moment when there is something worth looking at, but the moment when we are capable of seeing.

Civilizations die from philosophical calm, irony, and a sense of fair play quite as surely as they die of debauchery.