Zen personal trouble or crisis. Though Zen-narrative states that it is a "special transmission outside scriptures" which "did not stand upon words", Zen does have a rich doctrinal background, which is firmly grounded in the Buddhist tradition. It was thoroughly influenced by the Chinese understanding of Yogacara and the Buddha-nature doctrine, Zen integrates both Yogacara and Madhyamaka and the influence of Madhyamaka can be discerned in the stress on non-conceptual insight and the paradoxical language of the koans. Most essential are "the most fundamental teaching that we are already originally enlightened", and the Bodhisattva ideal, which supplements insight with Karuṇā, compassion
Zen 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 1893 is often pointed to as an event that enhanced the profile of Zen in the Western world. It was during the late 1950s and the early 1960s that the number of Westerners other than the descendants of Asian immigrants who were pursuing a serious interest in Zen began to reach a significant level. Japanese Zen has gained the greatest popularity in the West. The various books on Zen by Reginald Horace Blyth,