The _Brahmanas_ are priest-books; the _Upanishads,_ it is reasonable to say are Kshattriya-books;--you often find in them Brahmans coming to Kshattriyas to learn the Inner Wisdom. The _Brahmanas_ are books of ritual; the _Upanishads_ came much later that the _Brahmanas:_ that they represent a reaction towards spirituality from the tyranny of a priestly caste. But probably the day of the Kshattriyas was much earlier than that of the priests. The Marlow-Shakespear-Milton time was the Kshattriya period in English poetry; also the period during which the greatest souls incarnated, and produced the greatest work. So, perhaps, in this manvantara of the pre-classical Sanskrit literature, the Rig-Veda with its hymns represents the first, the Chaucerian period; but a Golden Age Chaucerian, simple and pure,--a time in which the Mysteries really ruled human life, and when to hymn the Gods was to participate in the wonder and freeddom of their being. Think, perhaps, as the cycle mounted to its hour of noon, esotericism opened its doors to pour forth an illumination yet stronger and more saving: mighty egos incarnated, and put in writing the marvelous revelations of the _Upanishads:_ there may have been a descent towards matter, to call forth these more explicit declarations of the Spirit. The exclusive caste-system had not been evolved by any means, nor was to be for many ages: the kings are at the head of things; and they, not the priests, the chief custodians of the Deeper Wisdom.--And then, later, the Priest-cast made its contribution, evolving in the _Brahmanas_ the ritual of their order; with an implication, ever growing after the beginning of the Kali-Yuga, that only by this ritual salvation could be attained. Not that it follows that this was the idea at first. Ritual has its place: hymns and chantings, so they be the right ones, performed rightly, have their decided magical value; we can understand that in its inception and first purity, this Brahmana literature may have been a growth or birth, under the aegis of Alawn of the Harmonies, of the magic of chanted song. And having said all this, and reconsidering it, one feels that to attribute these three branches of literature to a single manvantara is a woeful foreshortening. I suppose the Rig-Veda is as old as the Aryan Sub-race, which, according to our calculations, must have begun some 160,000 years ago.