Sometimes, however, this Ādi-Buddha is said to have produced all things through union with Prajñā (mentioned before, p. 202), in which case he is rather to be identified with the personal Creator Brahmā. Observe, moreover, that even in early times one of the Dhyāni-Buddhas—the one called Amitābha, ‘diffusing infinite light,’—lost his purely abstract character, and was worshipped by Northern Buddhists as a personal God. He is in the present day held by them to be an eternal Being, the ideal of all that is beautiful and good, who receives his worshippers into a heaven called Sukhāvati, ‘paradise of pleasures’ (see p. 183). But it must also be noted that neither Ādi-Buddha nor Amitābha, when regarded as personal gods, were held to be Creators of the World in the Christian sense. They were merely Supreme rulers outside and above it; for Northern Buddhists agree with Southern in thinking that the world exists of itself, and that its only Creator is the force of its own acts. We pass on now to consider how far and with what modifications the mythology of Brāhmanism and Hindūism was incorporated into Buddhism. I have already pointed out that although the Buddha changed the character of much of the existing mythology, he never prohibited his lay-followers from continuing their old forms of worship, or bowing down before the deities honoured by their fathers and grandfathers. Apart indeed from the shrewd policy of not assuming an attitude of hostility to popular creeds and usages, the tolerant tendency and universality of the Buddha’s teaching obliged him, in common consistency, to recognize, and as far as possible appropriate, the various religious elements existing around him, and to subordinate them to his own purposes. In fact, according to the theory of true Buddhism, as has been well pointed out by other writers, there was only one system of doctrine and only one Law—that Law (Dharma) which Gautama Buddha came to renovate for the benefit of the world in the present age. Hence all the apparently conflicting creeds, dogmas, forms, ceremonies, and usages of all nations, tribes, and races, were in reality mere outcomes, or dim recollections, or corruptions, of that one and the same universal Dharma which countless Buddhas had preached to mankind, in countless ages before the time of Gautama, and would continue to preach in ages to come. Hindūism, therefore, like all other creeds, was contained in the Dharma of Buddhism, and the great object of Gautama’s advent was not to uproot the old religion, but to purify it from error and restore it. It was on this account that he regarded the Hindū gods as occupying a place in his own system, though not without some modification of the nature of their supposed position, offices, and functions. And here it will be necessary to give an account of the later Buddhist theory of twenty-six successive tiers of heavens, one rising above the other (p. 120).