As the expression of the core theses of both natural law and legal positivism, the “unjust law theses” are the core theses of static philosophy of law which are used to deal with the relationship between morality and law. Due to different presuppositions of concepts of law, these two “unjust law theses” are consistent both in theory and practice rather than opposite in formal logic. Logical analysis and historical study have shown that both natural law and legal positivism can support freedom, democracy and rule of law, and can also object to totalitarianism, despotism and tyranny. As far as their practical function, the real significance of “unjust law theses” lies in the dynamic law-abiding process.The concept of obligation to obey law is on one hand related to the dynamic law enforcement, and on the other hand related to the theory of morality of law, thus is an important category as a theoretic pivot. The complication of the theories about obligation to obey law derives from the change of the idea of justice, and has some positive significance. It reveals the defects of natural law, advocates strongly for the thesis of Dura Lex, Sed Lex, contributes to the formation and enunciation of the self-correction and society-stabilizing mechanisms of democratic constitutionalism, and reminders us the practical character of jurisprudence. The theories about obligation to obey law are not only the development and application of “unjust law theses” in the domain of dynamic law-abiding, but also the fulfillment and justification of it.The “unjust law theses” and theses of law-abiding obligation which have coupling relationship between each other constitute two morality theses which appear sequentially in the theoretical system of natural law, and also constitute two separate theses in the theoretical system of legal positivism, thus form the systematic theory among morality, law and obligation to obey law. The systematic theory not only explains the realization of the “different but interlinked situation” between the two major schools, but also explains how they maintain justice, freedom and the rule of law together. The systematic theory also realizes the transformation of the philosophy of law from static to dynamic. |