Agency and Autonomy: A Formal Framework

With the recent rapid growth of interest in Multi-Agent Systems, both in artificial intelligence and software engineering has come an associated difficulty concerning basic terms and concepts. In particular, the terms agency and autonomy are used with increasing frequency to denote different notions with different connotations. In this paper we lay the foundations for a principled theory of agency and autonomy, and specify the relationship between them. Using the Z specification language, we describe a three-tiered hierarchy comprising objects, agents and autonomous agents where agents are viewed as objects with goals, and autonomous agents are agents with motivations.