There are many reasons why unwritten languages, like those of America, are more interesting, more promising in results, to the student of linguistics, than those which for generations have been cast in the conventional moulds of written speech.
Their structure is more direct, simple, transparent; they reveal more clearly the laws of the linguistic powers in their daily exercise; they are less tied down to hereditary formulæ and meaningless repetitions.
Would we explain the complicated structure of highly-organized tongues like our own, would we learn the laws which have assigned to it its material and formal elements, we must turn to the naïve speech of savages, there to see in their nakedness those processes which are too obscure in our own.
If the much-debated question of the origin of language engages us, we must seek its solution in the simple radicals of savage idioms; and if we wish to institute a comparison between the relative powers of languages, we can by no means omit them from our list. They offer to us the raw material, the essential and indispensable requisites of articulate communication.
As the structure of a language reflects in a measure, and as, on the other hand, it in a measure controls and directs the mental workings of those who speak it, the student of psychology must occupy himself with the speech of the most illiterate races in order to understand their theory of things, their notions of what is about them. They teach him the undisturbed evolution of the untrained mind.
As the biologist in pursuit of that marvellous something which we call “the vital principle” turns from the complex organisms of the higher animals and plants to life in its simplest expression in microbes and single cells, so in the future will the linguist find that he is nearest the solution of the most weighty problems of his science when he directs his attention to the least cultivated languages.
Convinced as I am of the correctness of this analogy, I venture to predict that in the future the analysis of the American languages will be regarded as one of the most important fields in linguistic study, and will modify most materially the findings of that science. And I make this prediction the more confidently, as I am supported in it by the great authority of Wilhelm von Humboldt, who for twenty years devoted himself to their investigation.