Feeling sad and happy refers to feeling sad or happy in real life, which is a feeling derived from specific events. It's from Hanshu Yiwenzhi.
Ban Gu wrote: "Since filial piety, Li Wu Yuefu has adopted ballads, so there is a generation of Zhao Zhizhi entrusted, and the wind of Qin and Chu is happy because of sadness." Emperor Wu of the Han Dynasty set up Yuefu to collect folk songs from all over the country, so there was the folk songs of Zhao's generation, the elegant demeanor of Qin Chu, which was produced because they had some feelings about specific things in real life and expressed their personal feelings about life.
Ban Gu introduced:
Ban Gu (32-92), a native of Fufeng Anling (now northeast of Xianyang, Shaanxi), was a famous historian and writer in the Eastern Han Dynasty. Ban Gu was born in a Confucian family, and his father Ban Biao and uncle Ban Si were famous scholars at that time. Ban Gu wrote a lot in his life.
As a historian, Hanshu is another important historical book in ancient China after Shiji, one of the first four histories. As a lyricist, Ban Gu is one of the "four masters of Han Fu", and Er Du Fu pioneered the Kyoto Fu and was included in the first article of Selected Works. At the same time, Ban Gu was also a theorist of Confucian classics, and White Tiger Yi Tong compiled by him was a masterpiece of Confucian classics at that time, which made Chen Weizhi's divinity theorized and codified.
Han Yuefu said:
Yuefu was first established in the Qin Dynasty, and it was an organization that managed the teaching of music and dance singing under the "Shaofu" at that time. In the early Han Dynasty, Yuefu did not exist. When Emperor Wu of the Han Dynasty arrived in Liu Che, he rebuilt Yuefu when he held a ceremony in the suburbs. Its duty is to collect folk songs or literati's poems for music, so as to prepare for the court's performance at sacrifices or banquets.
The poems it collected were later called "Yuefu Poetry" or "Yuefu Poetry" for short. It is a new poetic style after The Book of Songs and Songs of the South. Later, those who were unhappy were also called Yuefu or Quasi-Yuefu.
Yuefu poems in Han Dynasty also directly expressed the love and hate between men and women. Love and marriage works occupy a large proportion in the poems of Yuefu in the two Han Dynasties. Most of these poems are written by folk or lower-class literati. Therefore, when expressing love and hate in love and marriage, they all seem bold and bold.