The Bodhisattva vow, which many have taken when they received the 16 precepts, includes the vow to return again and again to this world until all beings attain Enlightenment. The underlying assumption is that Enlightenment, Nirvana and no rebirth is an aim of Buddhism. Zen Master Dogen’s phrase, “practice and Enlightenment are one” (修証一如), is a later development in Buddhism which merges the means with the ends. So, in one sense, concerning our self with rebirth is not necessary. However, even Zen Master Dogen talks about rebirth: “In ten thousand kalpas and thousands of lives, how many times are we born and how many times do we die? This cycle of lives is samsara [suffering], caused only by blind clinging to worldly affairs.”[5]