subtle teaching, often expressed through sudden shouts and blows with a staff, and for his wisdom and skill at oratory: Yet, his teachings are also described as "difficult to understand". According to Gyomay Kubose: "Yunmen's school is deep and difficult to understand since its mode of expression is indirect; while it talks about the south, it is looking at the north." One Word Barriers Yunmen is known for apparently meaningless short sharp single word answers, like "Guan!" (literally, "barrier" or "frontier pass") – these were called "Yunmen's One Word Barriers". These one-word barriers Koans An apocryphal anecdote that began circulating around the beginning of the 12th century has Yunmen going so far as to forbid any of his sayings or teachings from being recorded by his many pupils: Despite this, Yunmen is one of the greatest sources of "live words", "old cases", and paradoxical statements that would later evolve into the koan tradition, along with Zhaozhou (Japanese: Jōshū Jūshin). Most were collected in the Yúnmén kuāngzhēn chánshī guǎnglù (雲門匡眞禪師廣錄). Eighteen koans in the Blue Cliff Record involve Yunmen: A monk asked Yunmen (Ummon), "What is the teaching that transcends the Buddha and patriarchs?" Yunmen (Ummon) said, "A sesame bun." (From the Blue Cliff Record, case no. 77) Eight of Yunmen's sayings are included in Book of Equanimity, and five in The Gateless Gate: A monk asked Yunmen, "What is Buddha?" Yunmen said, "Dried shitstick." (From case no. 21, The Gateless Gate) Eighteen other koans were later discovered when a subsequent master of the Yunmen school, Xuedou Chongxian (Setchō Jūken, 980–1052 CE), published his Boze songgu, which contained one hundred "old cases" popular in his teaching line, in which the eighteen Yunmen koans were included. Further examples can be found in the Jen-t'ien Yen-mu, and the Yün-men Lu. While his short ones were popular, some of his longer ones were iconic and among the most famous koans: {{blockquote|Yun-men addressed the assembly and said: "I am not asking you about the days before the fifteenth of the month. But what about after the fifteenth? Come and give me a word about those days." And he himself gave the answer for them: "Every day is a good day."}} Lineage His disciples reputedly numbered 790, an unusual number of whom became enlightened. The Yunmen School flourished as one of the Five Schools for about 300 years, after which it was absorbed into the Linji