Evolution and Spread of Politeness Systems in Indo-European

In this paper, we investigate the phenomenon of pronominal politeness in the Indo-European languages and demonstrate that the processes of change of pronominal systems related to politeness follow two evolutionary regimes, one inside the 'Standard Average European' (SAE) linguistic area and another outside of it. Historical processes of language change differ at different levels of linguistic structure. In general, we presume that lower level, unconscious aspects of language change slowly over phylogenetic time, giving rise to patterns of relationship that can often be described as a family tree. Aspects of language that are consciously manipulated by speakers are expected to vary at a faster rate and to diffuse within areas of contact. Politeness is a social phenomenon, so we expect these systems to be highly susceptible to areal norms of interaction. We show that the similarities of SAE politeness systems can be accounted for with a model of convergence due to parallel evolution in a shared (social-demographic) environment, rather than by genealogical relatedness or borrowing. By quantifying and testing factors determining rates of structural change, we offer a novel and realistic approach that can explain similarities between distantly related languages sharing the same environment.