T He L Ogical M Odelling of C Omputational M Ulti - a Gent S Ystems

THE aim of this thesis is to investigate logical formalisms for describing, reasoning about, specifying, and perhaps ultimately verifying the properties of systems composed of multiple intelligent computational agents. There are two obvious resources available for this task. The first is the (largely AI) tradition of reasoning about the intentional notions (belief, desire, etc.). The second is the (mainstream computer science) tradition of temporal logics for reasoning about reactive systems. Unfortunately, neither resource is ideally suited to the task: most intentional logics have little to say on the subject of agent architecture, and tend to assume that agents are perfect reasoners, whereas models of concurrent systems from mainstream computer science typically deal with the execution of individual program instructions. This thesis proposes a solution which draws upon both resources. It defines a model of agents and multi-agent systems, and then defines two execution models, which describe how agents may act and interact. The execution models define what constitutes an acceptable run of a system. A run may then act as a model for a temporal logic; this logic can subsequently be used to describe and reason about multi-agent systems. A number of logics, with various properties, are developed in this way. Several detailed examples are presented, showing how the logics may be used for specifying and reasoning about multi-agent systems. The thesis includes a detailed literature survey.