A. Theoretical Bases.- I. Elements of Institutional Legal Positivism.- 1. The Ontology of Normative Institutionalism.- 2. The Language of Practical Realms.- 3. The Logic of Practical Thinking.- 4. Why do I Conceive of the Theory of Action as Formalist and why as Finalist?.- 5. Comments on the Definition and the Systematics of Institutions.- 6. Some Legal-Philosophical Implications of Normative Institutionalism.- 7. Why Legal Positivism?.- II. Towards a Formal-Teleological Theory of Action.- 1. Starting Points.- 2. Common-Sense Theory of Action.- 3. Behaviour as Transformation. Description of Actions. Meaningful Actions.- 4. Scope for Action and Freedom.- 5. Action as a Process of Selection based on Information.- 6. Identity and Difference of Actions.- 7. Teleology.- 7.1. The Relation between Teleology and Causality.- 7.2. Some Remarks on the Principle of Causality.- 7.3. Linear Causality and Causal Networks.- 7.4. Some Notes on the Ontology of Ends.- 7.5. Discovery, Optimisation and Choice of Means.- 8. On the Problem of the Dynamics of the System of Ends.- 9. Reducing the Complexity of Teleological Reflection.- 10. Remarks on the Methodology of the Analysis of Action.- III. The Significance of Logic for Modern Legal Theory. Fundamental Problems of Institutionalist Normativism.- 1. Main Areas of Logical Analysis in the Field of Jurisprudence.- 1.1. Logic as the Basis of the Structure Theory of Law.- 1.2. Rational Legal Argumentation.- 2. Logic, Law, and the Problems of the Logic of Norms.- 2.1. The Semantic Basis of the Logic of Norms and Action-related (or Practical) Disciplines.- 2.2. The Existence of Normative Regulations and the Institutionalist Conception of Law.- 2.3. Institutionalist Normativism and the Logic of Norms.- 3. The Idea of a Logic of Norms. Remarks on a Few Fundamental Problems.- 3.1. The Semantics of the Normative Sentences.- 3.2. Normative Sentence and Truth Value.- 3.3. Are there Normological Inferences.- 3.4. Logic of Norms or Deontic Logic.- 3.5. The Meta-postulate of the Non-derivability of ‘Ought’ from ‘Is’ and of ‘Is’ from ‘Ought’.- 3.6. Compound Normative Sentences, particularly the Hypothetical Normative Sentence.- 4. The Institutionalist Structure Theory of Law.- 5. The Plausibility Argumentation and Legal Hermeneutics in the Conception of Logicism.- B. Treatises on Legal Theory and Legal Sociology.- IV. Ontology, Hermeneutics and the Concept of Valid Law.- 1. The Legal Problem of Validity.- 2. ‘Is’ and ‘Ought’.- 3. The Field of Logical Operations.- 4. Institutional Ontology of Norms.- 5. The Juridical Definition of Valid Law.- 6. Legal Validity and Hermeneutics.- 7. Decision-Making Practice and Valid Law.- 8. Law and Purpose: On the Debate between Formalism and Instrumentalism.- V. Constitutional Theory in the Light of the New Institutionalism.- 1. Preliminary Remarks Concerning Terminology.- 2. The Projected Task.- 3. Fundamental Problems of Constitutional Theory.- 4. Theses of Institutional Legal Positivism which are relevant to the Constitutional Theory.- 5. Comments on the Fundamental Problems of the Constitutional Theory.- 5.1. State and Constitution.- 5.2. The Indispensability of the Constitution for the Existence of the State.- 5.3. The Effectiveness of the Constitution.- 5.4. The Institutional Unity of the System of Legal Sources.- 5.5. The Legal Stabilization of the Constitution: The Law establishing the Constitution (the Basic Law, the Constitutional Charter).- 5.6. The Essential Content of the Constitution.- 5.7. The Institutional Conception of Constitutional Knowledge.- 6. Political Power and the Structure of the Constitution.- 7. The Problem of Legitimacy.- 8. The Constitution and the Governing Ideas of Democracy.- VI. The Formal-teleological Theory of Action and Criminal Law.- 1. Some Problems Facing Criminal Law and the Theory of Action and the Goals of my Investigation.- 2. Characteristic Features of the Formal-teleological Theory of Action.- 3. The Concept of ‘Institutional Legal Positivism’.- 4. Fundamental Principles of the Teleological Theory of Action in Relation to Criminal Law.- 5. ‘Action’ and ‘Omission’ in Criminal Law Doctrine.- 6. The Generic Concept of Crime in Criminal Law.- 7. The Concept of Guilt.- 8. Notes on the Metatheory of Subsumption in Criminal Law.- VII. Institutional Theory and Institutional Legal Positivism.- 1. The Program of my Inquiry.- 2. A Characterisation of Institutional Legal Positivism.- 3. My Concept of Action and the Semantic Foundations of Practical Philosophy.- 4. The Concept of the Institution and its Typology.- 5. Institutional Theory in Modern Jurisprudence.- 6. Institutional Theories in Sociology.- 7. Institutional Legal Positivism contrasted with Juristic and Sociological Institutional Theories.- 8. Institutional Normativism and Sociology.- VIII. Sociology and the Normative Institutional Theory. Reflections on Helmut Schelsky’s Institutional Theory from the Point of View of the Normative Institutional Ontology.- 1. Behaviour and Action.- 2. The Language of Practical Philosophy.- 3. Normative Institutional Ontology.- 4. The Role of the Law in Schelsky’s Theory.- 5. Schelsky and Luhmann’s System-theoretical Method.- 6. Theses for a Theoretical Sociology.- C. Treatises on Legal Politics and Theory Of Justice.- IX. Legal-Political Analysis of Institutions.- 1. Legal Policy as a Scientific Problem of our Time.- 2. The Relevance of the Legal-Philosophical Approach to Legal-political Analyses.- 3. Characterization of the Science of Legal Policy.- 4. Rational Thinking and Practical Cognition.- 5. Two Types of Legal Argumentation.- 6. Rationality and the Legal-political Discussion.- 7. Types of Legal-political Argumentation.- 8. The Sources of Practical Dissent and of the Search for Consensus.- 9. Common Haws in Legal-Political Argumentations.- 10. The Conception of Democracy and Legal Policy.- 11. A Functional Analysis of Institutions and Democratic Legal Policy.- 12. Democracy and Power.- 13. Determinants of Political Control.- 14. The Role of the Sciences and of Experts in a Democracy.- 15. Democratic Legal Policy and the Concept of Justice.- X. The Conditio Humana and the Ideal of Justice.- 10.1. The Role of the Theory of Justice.- 10.2. The Anthropological Approach to the Problem of Justice.- 10.3. Ideals of Justice as Determinants of Action.- 10.4. The Analytical and Dialectic Character of Reflections on Justice.- 10.5. Formal Postulates of Justice.- 10.6. Natural Law or Convictions of Justice.- 10.7. Postulates of the Just Application of the Law.- 10.8. Balanced Role-play as a Postulate of Justice.- 10.9. Collective Action.- 10.10. Present-day Aspects of the Problems of Justice.- Original Sources.