GOAL agents instantiate intention logic

Various theories of cognitive or rational agents that use formal logic to define such agents have been proposed in the literature. Similarly, a range of more computationally oriented frameworks have been proposed for engineering rational agents. It remains interesting to explore the relation between these logical theories and existing computational agent frameworks that are used to program agents. First of all, by establishing a formal relation between agent logics and computational agent frameworks, agent logics may become a practical tool for reasoning about computational agents. Secondly, a formal relation may provide new insights into the kinds of agents that can be built using a particular computational agent framework. It may in particular highlight some of the assumptions built into logical as well as computational approaches. In this paper, we explore the relation between Intention Logic and the agent programming language Goal. This is a natural choice because Intention Logic and Goal use the same set of basic concepts to define agents, namely declarative beliefs and goals. We discuss various assumptions and identify some subtle differences between the two systems. We show that agent programs written in Goal can be formally related to specifications written in a fragment of Intention Logic. It follows that a weakened version of Intention Logic can be used to prove properties of Goal agents. In this sense, such agents can be said to instantiate Intention Logic.