The logic of action

In this article we provide a brief overview of the logic of action in philosophy, linguistics, computer science and artificial intelligence. The logic of action is the formal study of action in which formal languages are the main tool of analysis. The concept of action is of central interest to many disciplines: the social sciences including economics, the humanities including history and literature, psychology, linguistics, law, computer science, artificial intelligence, and probably others. In philosophy it has been studied since the beginning because of its importance for epistemology and, particularly, ethics; and since a few decades it is even studied for its own sake. But it is in the logic of action that action is studied in the most abstract way. The logic of action began in philosophy. But it has also played a certain role in linguistics. And currently it is of great importance in computer science and artificial intelligence. For our purposes it is natural to separate the accounts of these developments. 1 The logic of action in philosophy 1.1 Historical overview Already St Anselm studied the concept of action in a way that must be classified as logical; had he known symbolic logic, he would certainly have made use of it. (Cf. [33] and [101].) In modern times the subject was introduced by, among others, Alan Ross Anderson, Frederick B. Fitch, Stig Kanger, and Georg Henrik von Wright; Kanger’s work was further developed by his students Ingmar Porn and Lars Lindahl. The first clearly semantic account was given by Brian F. Chellas in [11]. (For a more detailed account, see [83] or the mini-history in [8].) Today there are two rather different groups of theories that may be described as falling under the term logic of action. One, the result of the creation of Nuel Belnap and his many collaborators, may be called stit theory (a term that will be explained in the next paragraph). The other is dynamic logic. Both are connected