Liu Yuxi (772 ~842), whose word is like a dream, called himself "Xingyang native, born in Luoyang". He also claimed to be a Zhongshan native, named Liu Sheng, and was the King of Zhongshan (a descendant of Xiongnu). Ministers, writers and philosophers in the Tang Dynasty were called "poets".
Liu Yuxi's philosophical thought has a distinct materialistic tendency. His main works are three essays about heaven. In the view of the world, his materialist thought is more progressive than Liu Zongyuan's. Regarding the relationship between nature and man, Liu Yuxi put forward the view that man and nature can win and use each other, which has a positive enterprising spirit. He believes that the reason why people produce idealism is closely related to social reality.