A grave illness, his biographers say, turned Yuanwu Keqin away from the scriptures. He was born in 1063 at Pengzhou, near Chengdu in Sichuan, to a family schooled in the Confucian classics, and he entered the Miaoji monastery there as a boy and studied monastic discipline and the sutras with teachers of doctrine. The sickness convinced him that reading and reciting texts would not carry him through death, and he went looking for Chan masters instead. For the rest of his life he taught on one question: where words help and where they get in the way.
The teacher who settled it was Wuzu Fayan, a master in the Yangqi branch of the Linji line; historians note that Yuanwu was in his forties when he finished his training with Wuzu, who died in 1104. The tradition tells that their first meeting went badly, that Wuzu sent him off with the advice to remember him when he lay in a fever, and that he fell ill at Jinshan and returned to him. It tells too how the breakthrough came: Wuzu raised a love poem in which a young woman calls her maid again and again for no reason except that her lover should hear her voice, and soon afterwards Yuanwu heard a rooster crow and understood. The poem is the point of the story. Its words carry no message of their own; they are there to make someone recognise a voice.
That is how he read the old cases, the remembered exchanges between earlier masters that Chan teachers set before their students. In the 1110s, at Jiashan in Hunan, he lectured on a hundred of them, each capped by a verse of Xuedou Chongxian, the eleventh-century master of the Yunmen house, and the lectures became The Blue Cliff Record. The verses are Xuedou's; the commentary is Yuanwu's, and it explains the cases, the poems and their allusions line by line. Yet the commentary keeps saying that the explanation is not the thing. One of his letters puts the distinction in the old Chan terms of a living phrase and a dead one: understand through the living phrase and you never forget it; understand through the dead one and you cannot even save yourself. A case grasped as a story with a meaning is a dead phrase. Ding-hwa Hsieh, a historian of Song Chan, reads his teaching as the bridge between the literary study of cases and the practice of concentrating on a single phrase of a case.
The practice belongs to his heir. Dahui Zonggao came to Yuanwu at the Tianning monastery in Kaifeng, the Northern Song capital, where Yuanwu had become abbot in 1124, and broke through there in 1125. Dahui later taught students to fix the mind on one word of a case until the doubt it raised gave way, and Chan tradition says that he burned the printing blocks of his teacher's book, alarmed at monks who talked too cleverly about the cases. Kaifeng fell to the Jurchen armies of the Jin in 1127. Yuanwu moved south with the dynasty, taught at Jinshan and at Yunju in Jiangxi, and received the name Yuanwu from Gaozong, the first Southern Song emperor. He went home to Zhaojue monastery in Chengdu and died there in 1135.
His other heir, Huqiu Shaolong, carried a different inheritance. Yuanwu wrote out a certificate of transmission for him in 1124. Its first half is now kept in the Tokyo National Museum as a National Treasure, the Nagare Engo or "drifting Yuanwu", named after a story that it reached the coast of Satsuma in a wooden tube. Most Japanese Rinzai teachers trace their line through Shaolong, and in Japan The Blue Cliff Record, reprinted around 1300 from surviving copies, became the foremost book of the school.