Professor Hans Kelsen is the leading exponent of the "pure" theory of law, which is attracting a great deal of attention abroad but as yet has received scant notice in the United States. His theory marks the culmination of the tendency toward a strictlylegaltheory, represented in the writings of K. F. von Gerber, Paul Laband, and Georg Jellinek. This movement aims to eliminate all purely metaphysical postulates—such as the natural law concepts—from legal theory, as well as to free it from the political tint which it so often manifests. It also endeavors to separate the validity of law from dependence on any personal authority.This attempt to "depersonalize" law is the last stage of a development that began with the passing of absolutism. At that time, ideas of a "general will" and of popular sovereignty—attended by a demand for "a government of laws and not of men" and by the introduction of the principle of separation of powers—made their appearance, only to be supplanted, more recently, by the concept of theRechtsstaat.