Thus the dominance of the Brahmans and their readiness to countenance every cult and doctrine which can attract worshippers explains the diversity of Indian religion, but are there no general characteristics which mark all its multiple forms? There are, and they apply to Buddhism as well as Hinduism, but in attempting to formulate them it is well to say that Indian religion is as wilful and unexpected in its variations as human nature itself and that all generalizations about it are subject to exceptions. If we say that it preaches asceticism and the subjection of the flesh, we may be confronted with the Vallabhâcâryas who inculcate self-indulgence; if we say that it teaches reincarnation and successive lives, we may be told that the Lingâyats[131] do not hold that doctrine. And though we might logically maintain that these sects are unorthodox, yet it does not appear that Hindus excommunicate them. Still, it is just to say that the doctrines mentioned are characteristic of Hinduism and are repudiated only by eccentric sects. Perhaps the idea which has had the widest and most penetrating influence on Indian thought is that conception of the Universe which is known as Saṃsâra, the world of change and transmigration. The idea of rebirth and the wandering of souls from one body to another exists in a fragmentary form among savage tribes in many countries, but in India it makes its appearance as a product of ripening metaphysics rather than as a survival. It plays no part in the Vedic hymns: it first acquires importance in the older Upanishads but more as a mystery to be communicated to the elect than as a popular belief and to some extent as the special doctrine of the military class rather than of the Brahmans. At the time of the Buddha, however, it had passed beyond this stage and was as integral a part of popular theology as is the immortality of the soul in Europe. Such expressions as the transmigration of souls or metempsychosis imperfectly represent Indian ideas. They are incorrect as descriptions of Buddhist dogmas, which start by denying the existence of a soul, and they are not entirely suitable to those Vedantic schools which regard transmigration as part of the illusory phenomenal world. The thought underlying the doctrine is rather that as a child grows into youth and age, so the soul passes from life to life in continuity if not in identity. Whatever the origin of the idea may have been, its root in post-Vedic times is a sense of the transitoriness but continuity of everything. Nothing is eternal or even permanent: not even the gods, for they must die, not even death, for it must turn into new life.