||Based on the fact that the law requires progressive methodology, the article grounds the conclusion that such methodology shall be social naturalism, which stems from the ideological ideas of the natural integrity of the world. The essence of the principle of social naturalism is to recognize that: 1) social life shall be consistent with the laws of nature, and 2) these laws are not the laws of the physical or biological nature — they are the laws of social nature, and 3) the role of human will and consciousness is that, they are the means of knowledge of the laws of social nature (including the laws of natural law) and compatibility of human life in society (in particular, by legislation) with them. The methodological role of social naturalism is defined by the fact that it is used as a tool to solve the «fundamental question of law»: what does the primary source of law — the laws of social nature or the will and conscience of people? In the light of social naturalism this issue is resolved as follows: the primary source of law is the laws of social nature (including the laws of «natural law»), which shall be studied and implemented in the legislation and practical using. According to the methodology of social naturalism, the doctrine of «natural law» and «positive law» is delineated in the article as follows: the essence of the doctrine of «natural law» is to recognize the primary source of law (i. e., the primary source of rights and duties) of the laws of social nature that shall be opened by the people endowed by will and consciousness and must be implemented in law and practice of its application, and the essence of the doctrine of «positive law» — in recognition of the primary source of law (i. e., the primary source of rights and duties ) directly will and consciousness, which are not compatible with the laws social nature, must be implemented in law and practice of its application. The value of social and naturalistic methodology in jurisprudence is that it paves the way for a progressive law and order, by opposing the spreading legal arbitrariness and legal illusions in the society.