that he had never used this material in the actual writing of his own book, though Cohen's ideas were attractive to him in their own right. This has resulted in one of the longest-running debates within the general Kelsen community as to whether Kelsen became a Neo-Kantian himself after the encounter with Cohen, or if he managed to keep his own non-Neo-Kantian position intact which he claimed was the prevailing circumstance when he first wrote his book in 1911. The Neo-Kantians, when pressing the issue, would lead Kelsen into discussions concerning whether the existence of such a Grundnorm was strictly symbolic or whether it had a concrete foundation. 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. On the other hand, to those seeking a practical reading, the Grundnorm corresponded to something directly and concretely comparable to a sovereign nation's federal constitution, under which would be organized all or its regional and local laws, and no law would be recognized as being superior to it. Symbolic and hypothetical readings of the basic norm In different contexts, Kelsen would indicate his preferences in different ways, with some Neo-Kantians asserting that late in life Kelsen would largely abide by the symbolic reading of the term when used in the Neo-Kantian context, and as he has documented. The Neo-Kantian reading of Kelsen can further be subdivided into three subgroups, with each representing their own preferred reading of the meaning of the 'Grundnorm,' which were identifiable as (a) the Marburg Neo-Kantians, (b) the Baden-Baden Neo-Kantians, and (c) his own Kelsenian reading of the Neo-Kantian school with which his writings on this subject are often associated, as found in his response to the Cohen exchange circa 1911-1914. Supplementary comments and references This has led to criticism from noted authors such as H. L. A. Hart, who refers to the theory as a `needless duplication' of the `living reality' of the courts and officials actually identifying the law in accordance with the constitution's rules. It is mystifying to posit a rule beyond these rules, which adds, superfluously in Hart's view, that the constitution is to be obeyed. Kelsen also attempted to explain International Law by applying the concept of there being a Grundnorm superior to all the