4-valued Logic for Agent Communication with Private/Public Information Passing

Song Yang, Masaya Taniguchi, Satoshi Tojo

Abstract: Thus far, the agent communication has often been modeled in dynamic epistemic logic, where each agent changes his/ her belief, restricting the accessibility to possible worlds in Kripke semantics. Prior to the message passing, in general, the sender should be required to believe the contents of the message. In some occasions, however, the recipient may not believe what he/ she has heard since he/ she may not have enough background knowledge to understand it or the information may be encrypted and he/ she may not know how to decipher it. In this paper, we generalize those messages that require special knowledge as private information and formalize that the recipient does not change his/ her belief receiving such private messages. Then, we distinguish the validity of the information from the belief change of the recipient; that is, even though the communication itself is held and the information is logically contradictory to his/ her original belief, the recipient may not change his/ h