Therefore we must needs acknowledge the diluvian tradition to be really indigenous in Mexico and not an invention of missionaries. We may doubt as to some particulars in some of the versions, though this arises chiefly from a preconceived idea, because they too much resemble the story in Genesis; but as to the fundamental tradition it is unassailable, and intimately connected with a conception not drawn from the Bible--and universally admitted to have existed--that, namely, of the four ages of the world. Between this conception, and that of the four ages or Yugas of India, and of the _manvantaras_ where the destruction of the world and the renewals of humanity alternate, there is an analogy which appeared very significant to Humboldt, MacCulloch, and M. Maury. It is one that justifies us in asking whether the Mexicans devised it independently or borrowed it more or less directly from India. The system of the four ages, inseparable in Mexico from that of the diluvian tradition, confronts us with the problem--ever recurring with regard to American civilization--of how far these are spontaneous and how far derived from Asia through Buddhist or other missionaries. In the present state of our knowledge we can as little solve this problem negatively as affirmatively, and all attempts made to come to a positive conclusion are premature and unproductive. Before discovering whence American civilizations came, we must thoroughly know what they were, nor attempt the arduous and obscure question of their origin till we frame a real American archæology on the same scientific basis and by the same methods as other archæologies. And in this respect Messrs. T. G. Müller and Herbert Bancroft appear to me greatly in advance of their precursors in this field of inquiry. For the present, all that can be done is, as I have attempted with Flood stories, to determine facts without pretending to draw inferences. Hence I should no longer boldly write, as I did eight years ago: "The Flood stories of Mexico positively prove the tradition of the Deluge to be one of the oldest held by humanity--a tradition so primitive as to be anterior to the dispersion of human families and the final developments of material civilization; which the Red race peopling America brought from the common cradle of our species into their new home, at the same time that the Semites, Chaldeans, and Aryans respectively carried it into theirs."[64] The fact is that among American peoples this tradition may not be primitive. We may indeed affirm that it was not borrowed from the Bible after the arrival of the Spaniards, but we cannot be equally confident that it was not the result of some previous foreign importation, the precise date of which we have no means of fixing.