The story is in the Autumn Floods chapter of the 《
庄子》. Huizi asks
子非鱼,
安知鱼之乐, 'you are not a fish, so how do you know the joy of fish?', and Zhuangzi turns the question back on him. The bridge is traditionally placed near today's Fengyang in Anhui, and the name came to stand for carefree delight in nature.