Signalling games: evolutionary convergence on optimality

Horn's division of pragmatic labour (Horn, 1984) is a universal property of language, and amounts to the pairing of simple meanings to simple forms, and deviant meanings to complex forms. This division makes sense, but a community of language users that do not know it makes sense will still develop it after a while, because it gives optimal communication at minimal costs. This property of the division of pragmatic labour is shown by formalising it and applying it to a simple form of signalling games, which allows computer simulations to corroborate intuitions. The division of pragmatic labour is a stable communicative strategy that a population of communicating agents will converge on, and it cannot be replaced by alternative strategies once it is in place.