Diversity in the origin of speech does not of necessity imply diversity in the origin of race. Thus with a unity of race, circumstances may be conceived in which independent tongues may have arisen in different localities; whereas with a diversity of race, but one language hypothetically may have been given to all. A common origin is probable, a diversity of origin is possible; neither can be proved or disproved. The radical differences in the structure of the three great types, the monosyllabic, the agglutinate, and the inflectional; and the inherent heterogeneities of the several families of the same type, as of the Chinese and Siamese, of the American and Turanian, or even of the Arian and Semitic, would seem to present insurmountable obstacles to the theory of a common origin; while on the other hand the wonderful mutations of types and trunks, the known transformations of language, and the identifications by some philologists, of the same stock in each of the three progressional stages, render the theory of a unity of origin in language equally probable. Therefore the question of unity or diversity of tongues, as we speak of unity or diversity of race, can be of but little moment to us. Language shows the connection between nations widely separated, leads us back beyond tradition into the obscure past, follows the sinuosities of migrations, indicates epochs in human development, points towards the origin of peoples, serves as a guide in following the radiation of races from common centres. Yet a similarity in the sound, or even in the construction of two words, does not necessarily imply relationship. Two totally distinct languages may have borrowed the same word from a third language; which fact would never establish relationship between the borrowers. When like forms are found in different languages, in order to establish a relationship, historical evidence must be applied as a test, and the words followed up to their roots.
Stripped of technicalities, the question before us is reduced to a few simple propositions. All men speak; there never yet was found a nation without articulate language. Aside from individual and abnormal exceptions, no primitive tribe has ever been discovered, where part of the people spoke, and part were speechless. Language is as much a part of man, as any physical constituent; yet unlike physical organs, as the eye, the ear, the hand, language is not born with the individual. It is not in the blood. The Caucasian infant stolen by Apaches, cannot converse with its own mother when restored to her a few years after.