I can now say with certainty that, with regard to the special character of races, philology confirms all the facts of physiology and history. Its conclusions however must be handled with extreme care, and when they are all we have to go upon, it is very dangerous to rest content with them. Without the slightest doubt, a people’s language corresponds to its mentality, but not always to its real value for civilization. In order to ascertain this, we must fix our eyes solely on the race by which, and for which, the language was at first designed. Now with the exception of the negroes, and a few yellow groups, we meet only quaternary races in recorded history. All the languages we know are thus derivative, and we cannot gain the least idea of the laws governing their formation except in the comparatively later stages. Our results, even when confirmed by history, cannot be regarded as infallibly proved. The further we go back, the dimmer becomes the light, and the more hypothetical the nature of any arguments drawn from philology. It is exasperating to be thrown back on these when we try to trace the progress of any human family or to discover the racial elements that make it up. We know that Sanscrit and Zend are akin. That is something; but their common roots are sealed to us. The other ancient tongues are in the same case. We know nothing of Euskara except itself. As no analogue to it has been discovered up to now, we are ignorant of its history, and whether it is to be regarded as itself primitive or derived. It yields us no positive knowledge as to whether the people who speak it are racially simple or composite. Ethnology may well be grateful for the help given by philology. But the help must not be accepted unconditionally, or any theories based on it alone.[143] This rule is dictated by a necessary prudence. All the facts, however, mentioned in this chapter go to prove that, originally, there is a perfect correspondence between the intellectual virtues of a race and those of its native speech; that languages are, in consequence, unequal in value and significance, unlike in their forms and basic elements, as races are also; that their modifications, like those of races, come merely from intermixture with other idioms; that their qualities and merits, like a people’s blood, disappear or become absorbed, when they are swamped by too many heterogeneous elements; finally, that when a language of a higher order is used by some human group which is unworthy of it, it will certainly become mutilated and die out. Hence, though it is often difficult to infer at once, in a particular case, the merits of a people from those of its language, it is quite certain that in theory this can always be done. I may thus lay it down, as a universal axiom, that the hierarchy of languages is in strict correspondence with the hierarchy of races.