Editing Morris Swadesh (section)

==Work in historical linguistics==
Swadesh is best known for his work in [[historical linguistics]]. Any language changes over centuries (consider, for example, the changes in English since the Middle Ages). Some languages diverge and become separate dialects, or languages that still belong to the same language family. Tracking similarities and differences between languages is part of historical linguistics. Swadesh proposed a number of distant genetic links among languages.

He was the chief pioneer of [[lexicostatistics]], which attempts to classify languages on the basis of the extent to which they have replaced basic words reconstructible in the proto-language, and [[glottochronology]], which extends lexicostatistics by computing divergence dates from the lexical retention rate.

Swadesh became a consultant with the [[International Auxiliary Language Association]], which standardized [[Interlingua]] and presented it to the public in 1951 (Esterhill 2000). In this role, he originated the lists of 100 and 200 basic vocabulary items, used (with some variation) in both lexicostatistics and glottochronology for comparison among languages. They have since been known as the [[Swadesh list]]s.

Some scholars considered Swadesh as a supporter of [[monogenesis (linguistics)|monogenesis]], the theory that all languages have a common origin: "Swadesh sought to show that all the world's languages are related in one large family" (Ruhlen 1994:215). Others believe that Swadesh proposed early linkages, but believed that languages diverged immediately among peoples, as he expressed in his major, but unfinished work, ''The Origin and Diversification of Language'' (1971), published posthumously.<ref>[http://strazny.com/writing/swadesh/ William Strazny, "Morris Swadesh: Critical Essay"], William Strazny Website, accessed October 25, 2009</ref>