Abstract

Deontic logic is an area of logic which investigates normative concepts, systems of norms, and normative reasoning. The word ‘deontic’ is derived from the Greek expression ‘déon’, which means ‘what is binding’ or ‘proper’. Thus, Jeremy Bentham used the word ‘deontology’ for “the science of morality,” and the Austrian philosopher Ernst Mally, who developed in the 1920s a system of the “fundamental principles the logic of ought,” called his theory ‘Deontik’. Normative concepts include the concepts of obligation (ought), permission (may), prohibition (may not), and related notions, such as the concept of right. Systems of deontic logic contain, in addition to the usual sentential connectives and quantifiers, logical constants which represent some of these normative concepts.