Dhyāna in Buddhism "silent illumination." This became the source of some differences in practice between the Línjì and Cáodòng schools. A kōan, literally "public case", is a story or dialogue, describing an interaction between a Zen master and a student. These anecdotes give a demonstration of the master's insight. Koans emphasize the non-conceptional insight that the Buddhist teachings are pointing to. Koans can be used to provoke the "great doubt", and test a student's progress in Zen practice. Kōan-inquiry may be practiced during zazen (sitting meditation), kinhin (walking meditation), and throughout all the activities of daily life. Kōan practice is particularly emphasized by
Zen lineage charts 南浦紹明 (1235–1308), who received transmission in China from the monk Xutang Zhiyu 虚堂智愚 (Japanese "Kido Chigu," 1185–1269) in 1265, who then returned to Japan in 1267. It was then spread by his student Shuho Myocho (second generation) and Kanzan Egen (third generation), who made it an influential school. The two main schools today are Takujū and Inzan, which both descent from Hakuin. Although it is difficult to trace when the West first became aware of Zen as a distinct form of Buddhism, the visit of Soyen Shaku, a Japanese Zen monk, to Chicago during the World Parliament of Religions in