Why did the development of traditional linguistics in China flourish in the Han Dynasty?

The Han Dynasty attached importance to literacy education, and the study of Chinese characters was developed. Some linguists and linguistic works in Han Dynasty can study the laws of Chinese characters from the reality of Chinese and Chinese characters, so it can be said that the achievements of linguistics in Han Dynasty marked the establishment of ancient linguistic science in China. China ancient linguistics is also called "primary school", and the research content of primary school mainly includes three aspects: exegetics, philology and phonology. The study of primary schools was mainly formed in the Han Dynasty. Erya in Han Dynasty was the beginning of exegetics, Shuowen Jiezi was the beginning of philology, and Shiming began to study the relationship between pronunciation and semantics. Linguistic research in Han Dynasty marked the maturity of ancient linguistics in China, and also laid the development path of linguistic research in China, which had a great influence on later generations.