Norms, action and agency

Speaker: Marek Sergot
Professor of Computational Logic
Imperial College, London.

Abstract: I will give a sketch of a formal language that combines a transition based account of action with a logic of expressions of the form 'agent x brings it about that A', or 'agent x sees to it that A', or 'the actions of agent x are responsible for, or the cause of, A'. No assumptions at all are made about the reasoning or perceptual capabilities of the agents---they can be human, or computer agents, or simple reactive devices; their actions could be intentional, deliberative, or unwitting. The resulting logic bears a resemblance to Ingmar Pörn's (1977) logic of 'brings it about' and to the 'stit' ('sees to it that') family of logics associated with Nuel Belnap and colleagues.

The account generalises naturally to talking about the collective actions of groups of agents: several different forms of (unwitting) collective agency can be identified. I will concentrate on simple illustrative examples, not on formal properties of the logic. I will also add some remarks about the prospect of using norms or 'social laws' as a mechanism for coordinating interactions between multiple, independently acting agents in a multi-agent system. Although that is an idea that has been promoted for a very long time, I can find little evidence to support it.