The Buddha then relates how, having taken food, he began to meditate and passed through four stages of contemplation, culminating in pure self-possession and equanimity, free alike from all feeling of pain or ease. Such meditation was nothing miraculous but supposed to be within the power of any trained ascetic. Then there arose before him a vision of his previous births, the hundreds of thousands of existences with all their details of name, family and caste through which he had passed. This was succeeded by a second and wider vision in which he saw the whole universe as a system of karma and reincarnation, composed of beings noble or mean, happy or unhappy, continually "passing away according to their deeds," leaving one form of existence and taking shape in another. Finally, he understood the nature of error[322] and of suffering, the cessation of suffering and the path that leads to the cessation of suffering. "In me thus set free the knowledge of freedom arose and I knew 'Rebirth has been destroyed, the higher life has been led; what had to be done has been done, I have no more to do with this world[323].' This third knowledge came to me in the last watch of the night: ignorance was destroyed, knowledge had arisen, darkness was destroyed, light had arisen, as I sat there earnest, strenuous, resolute[324]." On attaining enlightenment he at first despaired of preaching the truth to others. He reflected that his doctrine was abstruse and that mankind are given over to their desires. How can such men understand the chain of cause and effect or teaching about Nirvana and the annihilation of desire? So he determined to remain quiet and not to preach. Then the deity Brahmâ Sahampati appeared before him and besought him to preach the Truth, pleading that some men could understand. The Buddha surveyed the world with his mind's eye and saw the different natures of mankind. "As in a pool of lotuses, blue, red or white, some lotuses born in the water, grown up in the water, do not rise above the water but thrive hidden under the water and other lotuses, blue, red or white, born in the water, grown up in the water, reach to the surface: and other lotuses, blue, red or white, born in the water, grown up in the water, stand up out of the water and the water does not touch them." Thus did he perceive the world to be and he said to Brahmâ "The doors of immortality are open. Let them that have ears to hear, show faith."