William Dwight Whitney,
Language and the Study of Language
(1867)
“ We shall next pass in review the other great families into which the known forms of human speech are divided, noticing their most striking characteristics. Then will be taken up certain general questions, of prime interest and importance, suggested by such a review—as the relative value and authority of linguistic and of physical evidence of race, and the bearing of language upon the ultimate question of the unity or variety of the human species. Finally, we shall consider the origin of language, its relation to thought, and its value as an element in human progress. ”
