Buddhism Zen Buddhism is divided into two main schools: Rinzai (臨済宗) and Sōtō (曹洞宗), the former greatly favouring the use in meditation on the koan (公案, a meditative riddle or puzzle) as a device for spiritual break-through, and the latter (while certainly employing koans) focusing more on "shikantaza" or "just sitting". Zen Buddhism is primarily found in Japan, with some presence in South Korea and Vietnam. The scholars of Japanese Soto Zen tradition in recent times have critiqued the mainstream Japanese Buddhism for "dhatu-vada", that is assuming things have substantiality, a view they assert to be non-Buddhist and "out of tune
Enlightenment in Buddhism Sakyamuni's Buddhahood is celebrated on Bodhi Day. In Sri Lanka and Japan different days are used for this celebration. According to the Theravada tradition in Sri Lanka, Sakyamuni reached Buddhahood at the full moon in May. This is celebrated at Wesak Poya, the full moon in May, as Sambuddhatva jayanthi (also known as Sambuddha jayanthi). According to the Zen tradition, the Buddha reached his decisive insight on 8 December. This is celebrated in Zen monasteries with a very intensive eight-day session of "Rōhatsu". Enlightenment in Buddhism The English term enlightenment is the western translation of the abstract noun bodhi, (;