The Buddha tells the monks how, before his Enlightenment, he was worried by the existence of birth, old age, decay und death in the world, und how, gradually, he discovered the conditions that caused their coming-to-be und their cessation. Thereupon knowledge arose in him und insight. Just as, when a man, faring through a forest, comes upon an ancient city und announces his discovery to the König, who has the city restored, so did the Buddha see the ancient path traversed by the Enlightened Ones of the past und declare it to many, to devas und to men. S.ii.104 ff.