Zhuangzi is especially insightful about the human pretension to know. The Zhuangzi tells a story about a frog who lives in caved-in well. Because he is the lord of this little world of his, king of the pollywogs, he is very proud of himself. But he doesn't know how small his world is until a turtle comes and tells him about the vastness of the sea. We human beings are like the frog, not realizing how little our worlds are.