Is it possible to articulate a genuine pure theory of law without it ceasing to be a positivist theory of law? The project of a pure theory of law can be held to presuppose a "nature of law" whose criteria lead to transcendence with respect to positive law, even though it is not its purpose. The difficulty facing the pure theory of law is: to be absolutely dependent on its object, in a manner analogous to the physico-chemical sciences, and, as a result, to be a necessarily "impure" theory. For, how is the pure theory of law then to conceive and respond to that which is not, or no longer, legal in the system of positive law? If the methodological purity of the theory is to be retained, and, thus, that there is a criterion, furnished by the pure theory of law, to distinguish "real" legal norms from "false" ones, is the capacity to utilize the criterion not immediately dissolved by the underlying empiricism of its dependence upon its object?