Scott O'Dell

“Let's set the existence-of-God issue aside for a later volume, and just stipulate that in some way, self-replicating organisms came into existence on this planet and immediately began trying to get rid of each other, either by spamming their environments with rough copies of themselves, or by more direct means which hardly need to be belabored. Most of them failed, and their genetic legacy was erased from the universe forever, but a few found some way to survive and to propagate.”
― Neal Stephenson, Cryptonomicon

“Some humans would do anything to see if it was possible to do it. If you put a large switch in some cave somewhere, with a sign on it saying 'End-of-the-World Switch. PLEASE DO NOT TOUCH', the paint wouldn't even have time to dry.”
― Terry Pratchett, Thief of Time

“It is said that your life flashes before your eyes just before you die. That is true, it's called Life.”
― Terry Pratchett, The Last Continent

“It's not worth doing something unless someone, somewhere, would much rather you weren't doing it.”
― Terry Pratchett