在北京著名旅游景点颐和园里，有座小桥，叫做“知鱼桥”。很多人都不明白它为什么叫这个名字。知鱼桥，它知道鱼的故事吗？到底是谁给他起了这个名字呢？

The Garden of Harmonious Interest (The Summer Palace) is basically a garden of waterscape. Spanning the vast expanse of the lake and pools are five bridges, each quite different from the others. The most famous of them is the bridge known as "Knowing-the-Fishing-Bridge.” That’s not meant a bridge that knows stories about fish. It is said that more than 2,500 years ago during the Warring States Period, two philosophers named Zhuangzi and Huizi had an interesting argument by the side of a pond.

Zhuangzi said, "The fish swim to and fro in the water, they are really happy."

Huizi asked,” You are not a fish, how do you know they are happy?"

Zhuangzi answered, "You are not me, how do you know I don't know?"

Huizi said, "I am not you, so, I don't know you know it or not. You are not fish, so you don't know whether they are happy or not either!"

However, this famous talk had no result at last. And maybe you can up to the bridge and think about it. Do you think the fish are happy?