ments and records would contain references to only two races, and, although there might be no traditions to show that either of these had occupied the country longer than the other, the history of the language and the architectural and other remains would bear witness to the gradual introduction of one of them, and would show that in still more ancient times there were no traces of the existence of more than one race.
The interpretation of the relationships of the people to which he had been led by the study of the living inhabitants would now be far more than a working hypothesis, for everything which had been learned about their past history could be shown to be exactly what we should, by the hypothesis, expect, and he might therefore claim that this was a strictly scientific explanation of the theory of their origin. Although he would have definite proof of only one immigration, he would be fully warranted in concluding that the present inhabitants are the result of the crossing of four races; that at one time only one of these races inhabited the country, and that the other three have been introduced from outside at different times in a definite order.
The mass of evidence which he could bring forward in favor of this opinion would be sufficient to render it more probable than any other explanation of their origin, and would fully justify its acceptance as a scientific truth, but a little examination will show that the evidence is entirely circumstantial, and does not by any means amount to absolute proof, but only to a very great degree of probability. Although it may be true that it is very much more probable than any other explanation, this may be due to imperfect knowledge, and some other explanation may possibly be the true one.
In order to show this, let us suppose that the people of the country have another account of their origin, and believe that the four types were formed ages ago by the breaking up of an homogeneous race into four castes, which have ever since borne substantially the same relations to each other. Suppose that this belief bears such a relation to other traditions, and to certain manners and customs, that it has assumed, in their minds, a very great importance, and is regarded as a point of grave significance, resting upon irreproachable evidence. They might answer the anthropologist somewhat in this manner: You have certainly made out a very ingenious story, and have brought together a mass of evidence which appears to render your view very probable, but you have not shown that no other explanation is possible, and, as we do hold quite a different opinion upon evidence which is satisfactory to us, you must be mistaken. We are open to conviction, and are not unreasonable, but we must have proofs which leave no room for doubt, for as long as there is a chance that you are wrong we must hold to our old view. If you say that all natural knowledge is simply probable, and open to the possibility of error, give us proofs