Syntactic measuring of language relatedness

In this note we want to propose that, at the present stage of its development, the study of formal grammar may begin to enable us to reformulate at a more abstract cognitive level some of the main questions of the historical-comparative paradigm of the XIX century. In particular, we suggest that it is possible to develop a new type of taxonomic comparison, based on parametric syntax, to formally measure linguistic diversity and assess language relatedness. In order to do so, it is necessary to replace vague statements about the syntactic similarity or difference among languages by rigorous mathematical notions, which are made available precisely by the rise of the concept of parameter within the biolinguistic framework, initiated some decades ago by the works of Chomsky (1955, 1964, 1965) and Lenneberg (1964, 1967).As is usual in the history of natural science (especially cf. the illuminating remarks in Koyré 1948), accuracy of measurements is a sort of a priori methodological decision which may turn apparently chaotic empirical domains into previously unimaginable realms of objective and predictive scientific inquiry. We believe that in historical-comparative syntax time has come for exploring the consequences of assuming such a decision.