Abstract

The distinction between rules and principles is highly controversial. This is due to its significant impact on almost every fundamental philosophy of law and legal theory issue, for instance, the application of legal norms, the concept of the legal system, the relation between law and morality, or the structure of basic rights. The actual debate is based on three main theses: the “strong separation” thesis, the “weak separation” thesis and the “conformity” thesis. The author concentrates on the development of the “strong separation” thesis, first elaborated by Josef Esser, then developed by Ronald Dworkin and lately worked out by Robert Alexy. The several objections raised to Alexy´s thesis on principles as optimization commands will be discussed in detail. The author comes finally to his own formal description of principles as norms, with both an abstract and a concrete validity.