“Internal” and “External” Evidence in Linguistics

From a symposium on “The Problem of Data in Linguistics”, Proceedings of the Biennial Meeting of the Philosophy of Science Association, Vol. 1980, Volume Two: Symposia and Invited Papers (1980), pp. 598-604 598 “Internal” and “External” Evidence in Linguistics Arnold M. Zwicky The Ohio State University 1. Background It has become customary for linguists (especially generative lin- guists) to draw a distinction (initially rather unnatural for philoso- phers of science) between “internal” and “external” evidence. Usually classified as internal are data on the cooccurrence and alternation of linguistic elements in some language, as well as such systemic considerations as formal simplicity, economy, and the like. External evidence is everything else: the use of phonemes in rhyme schemes, patterns of acquisition, comparison to other languages, speech errors, dialect differences, historical change, and so on. The distinction is usually made invidiously–only internal evidence is probative–…