By determining law — so far as it is the subject of a specific science of law — as norm, it is delimited against nature; and science of law against natural science. But in addition to legal norms, there are other norms regulating the behavior of men to each other, that is, social norms; and the science of law is therefore not the only discipline directed toward the cognition and description of social norms. There other social norms may be called morals. and the discipline directed toward their cognition and description, ethics. So far as justice is a postulate of morals, the relationship between justice and law is included in the relationship between morals and law.

Pure Theory of Law (revised ed., 1960), 7. Moral Norms as Social Norms