How close is one language to another?

Abstract

Just how closely is English related to Danish, or to Gujarati? The idea of putting a number on the distance between languages was first explored in 1831 by Samuel Rafinesque, who invented lexicostatistics in order to win a competition in Paris of the Société de Géographie, to determine the origin of Asiatic negritos. Since there were no other contenders, he was awarded a 'médaille d'encouragement' worth only 100 francs rather than the advertised gold medal of 1000 francs. Rafinesque's negative finding showed the languages of disparate negrito peoples to be unrelated. It was never published, but his method was popularized by Jules Dumont d'Urville, who headed the jury.