Wherever sacred writings exist, we find in them the most ancient languages of the people who possess them; this is the case in Persia, China, Palestine, Arabia, and India; thus it is in these writings which are looked upon as being divinely inspired, that search must be made for the genesis of the successive thought of these peoples. But these ancient writings differ widely the one from the other; for the most part they contain ideas which are the product of various ages; often also, as in Greece, and Rome and Persia, we find ourselves confronted by thoughts or theories which had already arrived at a high degree of development, or are beginning to lose their first clearness. Only amongst the Hindoos is it possible to follow step by step the growth of the conception, and the transformation of the names which clothe them. The Vedas show us more clearly than any other literary monument in the world, the uninterrupted course of the evolution of language and thought from the first word pronounced by our ancestors to our own most recent reflection. India does not possess remains of ancient temples nor of ancient palaces. Edifices of this kind were probably unknown before the invasion of Alexander. The Hindoos have always felt themselves strangers in the land, and the constant efforts of the kings of Egypt and of Babylon to perpetuate their names during thousands of years, by means of bricks and blocks of stone, did not occur to them until suggested by foreigners. But on the other hand, from the most remote times, they have possessed sacred writings, and they still preserve them in their ancient form. The number of separate works in Sanscrit of which the manuscripts are still in existence is now estimated at more than ten thousand. What would Plato and Aristotle have said, had they been told that there existed in that India which Alexander had just discovered--if not conquered--an ancient literature, far richer than anything they possessed at that time in Greece, and dating back so far that the old Sanscrit which clothed the religious and philosophical thought of these early inhabitants was a dead language. This literature has not ceased to increase, and contains the canonical books of the three principal religions of the ancient world; the Zend-Avesta, the sacred books of the Magians, written in Zend, the ancient Persian; the Tripitaka, the sacred books of the Buddhists, which contain moral treatises, dogmatic philosophy, and metaphysics; and the sacred writings of the Brahmans called the Vedas.