DOI:
Abstract:
This paper presents a theory of informative communications among agents that allows a speaker to communicate to a hearer truths about the state of the world; the occurrence of events, including other communicative acts; and the knowledge states of any agent --- speaker, hearer, or third parties --- any of these in the past, present, or future --- and any logical combination of these, including formulas with quantifiers. We prove that the theory is consistent and compatible with a wide range of physical theories. We examine how the theory avoids two potential paradoxes, and discuss how these paradoxes may post a danger when this theory is extended.