No one knows the diversity in the world, not even to the nearest order of magnitude. ... We don't know for sure how many species there are, where they can be found or how fast they're disappearing. It's like having astronomy without knowing where the stars are.

Without a trace of irony I can say I have been blessed with brilliant enemies. I owe them a great debt, because they redoubled my energies and drove me in new directions.

Homo sapiens, the first truly free species, is about to decommission natural selection, the force that made us. Soon we must look deep within ourselves and decide what we wish to become.

In a purely technical sense, each species of higher organism-beetle, moss, and so forth, is richer in information than a Caravaggio painting, Mozart symphony, or any other great work of art.

You teach me, I forget. You show me, I remember. You involve me, I understand.

Go as far as you can, [young scientists]. The world needs you badly.

That's the way to get young people. Once they see there are wonderful things to hunt for, to rediscover a species that was thought to be extinct or is extremely rare, to be the first to see a nest, to discover a new species unsuspected close to your home - these are things, I think, with a little education and excitement and the right kind of natural history would actually start a movement that makes going back to nature a profitable adventure.