In his choice of texts, the Editor has been faced with the difficult task of selecting, from among the author's more than 600 publications, those of the greatest philosophical interest. It is chiefly the topics of value-rela­ tivism and the logic of norms that have been kept in view. The selection has also been guided by the endeavour to reprint, so far as possible, texts which have not hitherto appeared in English. At times, however, this aim has had to be discarded, in order to include works of key im­ portance and also the latest expressions of Kelsen's view. In addition to the two topics already mentioned, the Editor has con­ sidered Kelsen's discussions of the causal principle to be so far worthy of philosophical attention, that some writings on causality and account­ ability have been included in this collection of philosophical studies. OTA WEINBERGER Hans Kelsen died on April 19th, 1973. Only his work now lives, for the inspiration of future generations of jurists and philosophers. Graz, 25th April, 1973 OT A WEINBERGER TRANSLATOR'S NOTE I am obliged to the Editor for his careful scrutiny of the translation, which has led to a number of corrections and improvements in the text.

I. What is Justice?.- II. The Idea of Natural Law.- III. God and the State.- IV. Law and Morality.- 1. Moral Norms as Social Norms.- 2. Morality as the Regulation of Internal Behaviour.- 3. Morality as a Primitive Order without Coercive Character.- 4. Law as a Part of Morality.- 5. Relativity of Moral Value.- 6. Separation of Law and Morality.- 7. Justification of Law by Morality.- V. State-Form and World-Outlook.- VI. The Foundation of the Theory of Natural Law.- VII. Causality and Accounting.- VIII. The Emergence of the Causal Law From the Principle of Retribution.- IX. On the Concept of Norm.- X. Law and Logic.- 1. Contradiction of Natural Law.- 2. Morality and Law.- 3. The Issue Clouded by Roman Law.- 4. No Imperative without an 'Imperator'.- 5. The Analogy is Misleading.- 6. Statement and Norm.- 7. Law is an Act of Will.- 8. Statement and Truth.- 9. Legislator and Judge.- 10. Robber and Judge.- 11. Statute Book and Textbook.- 12. Natural and Legal Science.- 13. Of the Spirit of the Laws.- 14. Logic and Psychology.- 15. 'Juridical Logic'.- XI. Law and Logic Again. On the Applicability of Logical Principles to Legal Norms.- XII. On the Practical Syllogism.- XIII. Derogation.- XIV. Norm and Value.- Index of Names.- Index of Subjects.