Jap., lit "discipline schoorl", school of Japanese Buddhism that developed out of the original Chinese form of this school (Lu tsung). It was brought to Japan in the year 754 by the Chinese monk Chien-chen (Jap., Gan-jin). The school stresses the literal observance of the Vinaya rules for Buddhist life. It attaches special value to the correct performance of the ordination ceremony. The Ritsu school survives until the present but has never been of great importance. This can be attributed to a strong tradition of less literal observance of discipline in the other Buddhist schools. These schools attach less value to the rule itself than to the spirit behind it. Another factor in the minimal influence of the Ritsu school was the appearance of a Mahayana ordination ceremony in the Tendai school.

Emperor Shomu (724-748), who strongly favored the diffusion of Buddhism in Japan, wanted to bring a competent teacher from China to Japan, who would convey deep and thorough knowledge of the disciplinary rules to Japanese monks and nuns. After the arrival of Chien-chen in Japan, the emperor had a monastery specially built for him with an ordination hall attached. The monk Saicho, who was ordained in this monastery, nevertheless later declared this kind of Hinayana ordination not valid and developed a "bodhisattva ordination" according to Tendai teachings, which was purely Mahayana and less strictly formal. However, because of strong protest on the part of the other schools, this way of consecrating a monk was not recognized until after Saichao's death. Then it was recognized by imperial decree. Later, other schools, such as Zen and Jodo, adopted this form of ordination.

(excerpted from "The Encyclopedia of Eastern Philosophy and Religion", Shambhala, Boston)