You are not a fish, how do you know that fish are happy?

From "Zhuangzi. Autumn Waters".

Original text

Zhuangzi and Huizi were traveling on Haoliang.

Zhuangzi said: "The fish swims calmly, which is the joy of fish." "Happiness?"

Zhuangzi said: "I am not a son, how do you know that I don't know the joy of fish?"

Huizi said: "I am not a son, so I don't know it; I am not a son." It's all fish, you don't know the joy of fish."

Zhuangzi said: "Please follow the principle. Zi said, 'You know the joy of fish.' Since you know that I know it, ask. I, I know what is above the Hao River."

Translation

Zhuangzi and Huizi were walking on the bridge of the Hao River.

Zhuangzi said: "The minnow swims very calmly. This fish is very happy."

Huizi said: "You are not a fish, how do you know the happiness of fish?"

Zhuangzi said: "You are not me, how do you know that I don't know the happiness of fish?"

Huizi said: "I am not you, so of course I don't know how you feel; you are not originally a fish, "You don't know the happiness of fish, that's for sure."

Zhuangzi said: "Please find the original. What you said about "how do you know the happiness of fish" is that (you) have already. You know what I feel and then you ask me. I learned about the happiness of fish on the Hao River.

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