[4] The study makes a rigorous examination of the "two swords doctrine" of Pope Gelasius I, along with Dante's distinct sentiments in the Roman Catholic debates between the Guelphs and Ghibellines.

The closing chapter of Kelsen's study of political allegory in Dante also was important for emphasizing the particular historical path which led directly to the development of modern law in the twentieth century.

[6] In the case of Machiavelli, Kelsen saw an important counter-example of an exaggerated executive part of government operating without effective legal restraints on responsible conduct.

For Kelsen, this was instrumental in the orientation of his own legal thinking in the direction of government strictly according to law, eventually with a heightened emphasis on the importance of a fully elaborated power of judicial review.

[6] Kelsen's time at Heidelberg was of lasting importance to him in that he began to solidify his position of the identity of law and state from the initial steps he observed as being taken by Jellinek.

"[8] Kelsen was joined in this critique by the distinguished French jurist Léon Duguit, who wrote in 1911: "Self-limitation theory (vis Jellinek) contains some real sleight of hand.

In the late 1920s, these were followed by Die philosophischen Grundlagen der Naturrechtslehre und des Rechtspositivismus (The Philosophical Foundations of the Doctrine of Natural Law and Legal Positivism).

Kelsen was supported in his position by Adolf Merkl [de; pt] and Alfred Verdross, while opposition to his view was voiced by Erich Kaufman, Hermann Heller, and Rudolf Smend.

", in which he defended in plain terms the importance of judicial review over and against the excessive form of executive authoritarian government which Schmitt was promulgating in the early 1930s.

Both Heinrich Triepel in 1924 and Gerhard Anschütz in 1926 were unsuccessful in their explicit drive to instill a strong version of judicial review in Germany's Weimar Constitution.

[27] In the introductory essay to the volume, Behr and Rosch indicate that the Geneva faculty under the examiners Walther Burckhardt and Paul Guggenheim were initially quite negative concerning Morgenthau's Habilitationschrift.

In the early 1960s an expanded version was set up in proof but was withdrawn at Kelsen's insistence (and considerable personal expense in reimbursing the publisher), for reasons that have never become clear.

[39] Kelsen is considered one of the preeminent jurists of the 20th century and has been highly influential among scholars of jurisprudence and public law, especially in Europe and Latin America although less so in common-law countries.

In drafting the constitutions for both Austria and Czechoslovakia, Kelsen chose to carefully delineate and limit the domain of judicial review to a narrower focus than was originally accommodated by John Marshall.

Kelsen, during the time period of his education and legal training in fin-de-siecle Europe, had inherited a highly ambiguous definition of natural law which could be presented as having metaphysical, theological, philosophical, political, religious, or ideological components depending on any one of numerous sources who might desire to utilize the term.

[49] As summarized by Sandrine Baume,[50] "In 1927 [Kelsen] recognized his debt to Kantianism on this methodological point that determined much of his pure theory of law: 'Purity of method, indispensable to legal science, did not seem to me to be guaranteed by any philosopher as sharply as by Kant with his contrast between Is and Ought.

The principles of explicitly defined sovereignty became of increasing importance to Kelsen as the domain of his concerns extended more comprehensively into international law and its manifold implications following the conclusion of WWI.

After Kelsen completed his doctoral dissertation on the political philosophy of Dante, he turned to the study of Jellinek's dualist theory of law and state in Heidelberg in the years leading to 1910.

Kelsen recognized the province of society in an extensive sense which would allow for the discussion of religion, natural law, metaphysics, the arts, etc., for the development of culture in its many and varied attributes.

Very significantly, Kelsen came to the strong inclination in his writings that the discussion of justice, as one example, was appropriate to the domain of society and culture, though its dissemination within the law was highly narrow and dubious.

One significant example of this involves his introduction and development of the term Grundnorm which can be briefly summarized to illustrate the diverse responses which his opinion was able to often stimulate in the legal community of his time.

Regarding Kelsen's original use of the term Grundnorm, its closest antecedent appears in writings of his colleague Adolf Merkl [de; pt] at the University of Vienna.

Merkl was developing a structural research approach for the understanding of law as a matter of the hierarchical relationship of norms, largely on the basis of their being either superior, the one to the other, or inferior with respect to each other.

Another form of the reception of the term originated from the fairly extended attempt to read Kelsen as a neo-Kantian following his early engagement with Hermann Cohen's work in 1911,[58] the year his Habilitation dissertation on public law was published.

This has led to the further division within this debate concerning the currency of the term Grundnorm as to whether it should be read, on the one hand, as part and parcel of Hans Vaihinger's "as-if" hypothetical construction.

While still in Austria, Kelsen entered the debate on the versions of Public Law prevailing in his time by engaging the predominating opinions of Jellinek and Gerber in his 1911 Habilitation dissertation (see description above).

In addition to this debate, Kelsen had initiated a separate discussion with Carl Schmitt on questions relating to the definition of sovereignty and its interpretation in international law.

A third example of the controversies with which Kelsen was involved during his European years surrounded the severe disenchantment which many felt concerning the political and legal outcomes of WWI and the Treaty of Versailles.

[66] Kelsen also became a significant contributor to the Cold War debate in publishing books on Bolshevism and communism, which he reasoned were less successful forms of government when compared to democracy.

The formation of the European Union recalled many of his debates with Schmitt on the issue of the degree of centralization which would in principle be possible, and what the implications concerning state sovereignty would be once the unification was put into place.