Beginning with the idea of a holy spirit, without admixture of anything material, and forming the abstract opposite of nature, the Brahmans had discovered that it is the duty of man to raise the spiritual above the corporeal. The more excitable the nerves, the more receptive the senses, the warmer the passions in that climate and nation, the more energetic was the reaction of the spirit against the flesh, the more stringent the command to become master of the senses and the body, to annihilate the senses. It is true that the material world also had emanated from Brahman; even matter had come from him. But this was an adulteration of the pure Brahman; it was the non-sensual, not the material side of the world which was the pure Brahman. Hence for the Brahmans these two factors, the material and spiritual side, were again completely separated. Hence the ethical problem was not to arrange the world of sense for the objects of the spirit, to raise the soul to the mastery over the body, and purify the sensual action by the spirit, but the annihilation of the sensual elements by the soul, the removal and destruction of the body--in a word, asceticism. Out of the absolute annihilation of the material existence of man, his true intellectual being--his real nature, _i.e._ Brahman--is to arise; it is only after the complete destruction of the life of sense and the body that man can plunge into the pure spirit. As this pure spirit could only be looked upon as a negation of nature and the world, and was only regarded in that light, and as it had no other quality but that of being non-material, the command to think of Brahman and nothing but Brahman, amounted to nothing less than this: on the one hand, every distinct individual intuition was to be rejected and avoided; on the other, it was a duty to develop the conception of an indefinite and indefinable unity, in opposition to the multitudinous variety of the world and nature. A conception of unity which altogether disregards the plurality comprising it is nothing more than persistence in vacuity. Thus the negation of the spiritual life was demanded beside that of the bodily life; and this command was equivalent to bodily and spiritual self-annihilation.