A Logical Model of Intention and Plan Dynamics

International audienceWe propose a formal semantics of intention and plan dy- namics based on the notion of local assignment. The function of a local assignment is to change the truth value of a given proposition at a specific time point along a history. We combine a static modal logic including a temporal modality and modal operators for mental attitudes belief and choice, with three kinds of dynamic modalities and corresponding three kinds of local assignments operating on an agent?s beliefs, on the agent?s choices and on the physical world. An agent?s intention is defined in our approach as the agent?s choice to perform a given action at a certain time point in the future and two operations called intention generation and intention reconsideration are defined as specific kinds of local assignments on choices. In Sec- tion 1 we introduce a static logic of time, action, and mental attitudes. In Section 2 we add the dynamic notion of local assignment to the logic of Section 1. In Section 3, we focus on two specific kinds of local assignment on choice which allow to model the processes of intention and plan generation and reconsideration