"Jujitsu," Mr. Kroeger said, "means in Japanese 'the gentle art.' It's a form of judo, which means 'the gentle way of life.' It was started by a doctor from Nagasaki who was watching a cherry tree and a willow tree during a storm. He saw that the cherry tree, which stood up to the wind, had all its branches broken, while the willow tree, which bent with the wind, wasn't hurt. That gave him the idea for jujitsu."
In school my teacher told us this story. Now I found it here: One bends, the other breaks