At the beginning of the article, with concise and vivid pen and ink, it depicts the grand occasion of Qiu Shui's total love, which naturally leads to Hebo's pride and complacency. Then, from the perspective of Hebo, who flows into the sea from the east, he saw the vastness of the sea, which naturally led to Hebo's shame and sigh about the sea. In this simple and clear natural phenomenon, the reader's vision is as broad as Herb's. This passage can be described as beautiful, and the brushwork and water potential seem to have merged into one, leaving no boundaries. And the discussion of Beihai Ruo will naturally flow out with this image. Beihai brilliantly explained that cognitive judgment is always limited by living conditions with three metaphors: "well frog", "summer worm" and "bending time". In addition, three contrasting metaphors, namely "empty in osawa", "rice in the barn" and "millions in the horse", vividly illustrate the difference between small and big. This passage can be said to be a wonderful display of the article "Little knowledge is not as good as great knowledge" in Happy Travel. When Hebo got rid of the self-righteous prejudice and then fell into the new prejudice that is too small to be too big, Beihai expounded his relativistic view of time and space and change from four aspects: infinite quantity, endless time, impermanence in division, and ultimately unreasonable, and further extended from this insight of natural philosophy that "what people know is not what they know". It's not like when you're born. It is also the exertion of the theory that "my life is limited, but my knowledge is also limited". With the limit, it is dangerous. "