“The power of rules” is one of the most important subjects in moral philosophy and political philosophy.“The interest-based contractarianism” attempts to derive the power of rules from self-interseted rationality, thus it is totally different from ontology. “The interest-based contractarianism” tries to resolve the conflic bewteen the self-interseted rationality and the power of rules. In this way , the new social contrac view shows us another dimension about rationality and rules , and we are able to find this dimesnion in “Real Right Law of the People’s Republic of China”.