"Competition is the law of the jungle, but cooperation is the law of civilization"
- Peter Kropotkin (1842-1921)

UPDATE:
Thanks to some responders, found out that this “quote” is not an actual quote of Kroptkin. He actually thought the “jungle” showed cooperation as well.
A thread on how this misquote has been spread:
https://www.reddit.com/r/Anarchy101/comments/18r9zg5/comment/kf07vw4/