Liezi is not a fake by Zhang Zhan, which has been accepted by more and more people. However, the academic circles still generally believe that Liezi today may be the work of Wei Jin people in terms of ideological content and language. From the linguistic point of view, Liezi is regarded as the work of Wei Jin people, and Yang Bojun is the most representative scholar who holds this view. Later, according to the language, most people who claimed that Liezi might be the work of Wei Jin people came from this article by Yang Bojun.
Yang Bojun said in this article, "If we are proficient in the history of Chinese, any forged ancient book, no matter how clever the forger is, can find out his flaws in language. According to these flaws, we can identify it as a fake book, and even identify its writing age. So I said that it is one of the scientific methods to identify ancient books from the perspective of China history. But this method can only be used in a certain range and to a certain extent; Especially for the identification of ancient books in the pre-Qin period, it is unreliable to abuse this method.
The main reason is that the loss of ancient books in pre-Qin period is too serious. After the turmoil in the Warring States, the burning of books by Qin Shihuang and the burning of books by Chu people at the time of Qin's death, the records in Liu Xiang-Liu Xin's Seven Laws and Han Shu Yi Wen Zhi are less than one tenth of the original ancient books in the pre-Qin period. After Dong Zhuo's Rebellion, Yongjia Rebellion and successive disasters, fortunately, less than one tenth of the pre-Qin ancient books recorded in Hanshu Yiwenzhi have been preserved so far. In other words, the pre-Qin ancient books have been preserved so far, which is less than the original 1%. The development of language is a continuous and long process. The language in the Qin and Han Dynasties evolved from the language in the pre-Qin period, especially in the Spring and Autumn Period and the Warring States Period. Words that were popular in the Qin and Han Dynasties, especially from the unification of Qin Dynasty to the early Han Dynasty, were bound to spread to a certain extent in the pre-Qin Dynasty, especially in the Warring States Period, and it was natural for writers or thinkers at that time to adopt them into their own works.