Internal and External Forces in Typology: Evidence from Iranian Languages

In this article the debate in the literature on the role of internal and external forces in shaping the typological features of a language is evaluated in the light of the evidence from Iranian languages. In this study the Greenbergian word order correlations as presented in Dryer ( 1992, in Press) are adopted as the theoretical and statistical framework. On that basis the common typological parameters of the languages studied are identified and the variations in them are also specified. Then the potential and actual areas of convergence/ interference of these languages as substrata with Modern Persian as the superstratum are discussed. Despite instances of convergence/ interference, the findings reveal the strength of the parameters of variation at the present time. However, the situation in regard to some of these languages is such that instances of even language shift in near future is not unexpected. Hence, it appears that in the Iranian languages studied the impacts of the internal and external forces in typology are potential and relativistic'.