A Modal Semantics for an Argumentation-Based Pragmatics for Agent Communication

In this paper we present a modal semantics for our approach based on social commitments and arguments for conversational agents. Our formal framework based on this approach uses three basic elements: social commitments, actions that agents apply to these social commitments and arguments that agents use to support their actions. This framework, called Commitment and Argument Network (CAN), formalizes the agents’ interactions as a network in which agents manipulate commitments and arguments. More precisely, we propose a logical model (called DCTL*CAN) based on CTL* and on dynamic logic for this framework. The advantage of this logical model is to bring together social commitments, actions, argumentation relations, and the relations existing between these three elements within the same framework. Our semantics makes it possible to represent the dynamics of agent communication. It also allows us to establish the important link between social commitments as a deontic concept and arguments. The final objective of this paper is to propose a unified framework for pragmatics and semantics of agent communication by defining logic-based protocols.