Communication frictions and equilibrium pragmatics

Abstract This paper introduces a common-interest communication game that generates pragmatics, where meaning emerges from the use of a preexisting language under equilibrium selection driven solely by efficiency. A key feature is that the sender describes the current state to the receiver by combining preexisting statements. This approach allows us to formalize two communication frictions: (i) longer descriptions incur higher costs, and (ii) with some probability, the receiver interprets only the conventional meaning. The absence of one friction leads to some efficient equilibria exhibiting pragmatics that disregards conventional meaning. However, when communication costs are sufficiently small, given the other friction, any efficient equilibrium exhibits natural pragmatics that refines conventional meaning, reflecting the context provided by the probability distribution of states. The resulting equilibrium pragmatics aligns with major linguistic theories, including Grice’s cooperative principle (1975) and Sperber and Wilson’s relevance theory (1986).