Proceedings of the Annual Meeting of the Cognitive Science Society

What cognitive mechanisms support the emergence of linguis-tic conventions from repeated interaction? We present re-sults from a large-scale, multi-player replication of the clas-sic tangrams task, focusing on three foundational propertiesof conventions: arbitrariness, stability, and reduction of ut-terance length over time. These results motivate a theory ofconvention-formation where agents, though initially uncertainabout word meanings in context, assume others are using lan-guage with such knowledge. Thus, agents may learn aboutmeanings by reasoning about a knowledgeable, informativepartner; if all agents engage in such a process, they success-fully coordinate their beliefs, giving rise to a conventionalcommunication system. We formalize this theory in a compu-tational model of language understanding as social inferenceand demonstrate that it produces all three properties in a sim-plified domain.