Historical materialism correctly solves the basic principle of the relationship between social existence and social consciousness (see social existence determines social consciousness), which is the fundamental starting point of various social sciences. Society is a special part of the material world. Without understanding its particularity, it is impossible to correctly apply the principle of general materialism and dialectical thought to the process of understanding social history. Historical materialism reveals the decisive role of labor in the formation and development of human society, points out the decisive role of social material relations in political relations and ideological relations, clarifies that the relationship between social existence and social consciousness is the fundamental problem of historical view, and lays the fundamental principle of materialist epistemology for various social sciences. Historical materialism explains social consciousness from social existence, production relations from productivity, superstructure from economic basis, and the law of social development from the relationship between productivity, production relations and superstructure, which has universal guiding significance for studying various fields of social life. Only by following this line of understanding can all social sciences correctly sum up empirical materials and draw scientific conclusions.