He said in "Nine Books of Yuan Zaju": "Since I came to North Korea, I have become older and more knowledgeable. Every time you talk to people, ask more current events, read more history and seek more truth. I just know that articles are written in time and songs and poems are written for things. "
There are two meanings here: on the one hand, it reflects current events, that is, in the preface to Qin Zhongyin, it is said that "when Zhenyuan and Yuanhe are in harmony, they should be given to Chang' an, and those who are sad when they hear about it will sing their stories directly"; On the other hand, it is written for reality, that is, it is called "making up time" in "Nine Books to Make Up Time with Yuan". But the purpose is for reality. Bai Juyi inherited the realistic spirit of Han Yuefu, and from the social reality of the Middle Tang Dynasty, he put forward the idea that "articles should be written in time, songs and poems should be written", which is a great contribution to the theory of realistic poetry.