Dialectics and historical linguistics have always been closely related. Dialect geography was originally designed to test the hypothesis that the phonetic evolution of new grammar schools in the19th century is no exception. Its research results were later used to construct early languages and explain how it differentiated. One of the main research purposes of social dialectology is to propose a more possible language evolution model. Dialectics also has some connections with general linguistics. In the past, dialect geography and structural linguistics were basically studied independently. However, one of the basic starting points of social dialectology is to establish a language theory that conforms to language reality and is suitable for social communication. It opposes the theory that language research has been divorced from social communication since Saussure, and thus divorced from context or based only on language data.