 Meantime, Buddhism came armed with a paradox that would delight thinkers of a Daoist turn of mind—the fabled paradox of desire. Rebirth was caused by desire and Nirvana could be achieved only by the cessation of desire. That meant that in order to achieve Nirvana, one had to cease to want to achieve it. This argument informs the Mahayana notion of a Bodhisattva, who qualifies for Nirvana but voluntarily stays behind in the cycle of rebirth to help the rest of us. Enlightenment could only be achieved all at once. (This conclusion was also a consequence of the Buddhist view that the ego is an illusion.) The Mahayana wing of Buddhism was the more successful in China because this implicit egalitarianism—everyone could be Buddha, just as everyone can be a Daoist or Confucian Sage.