Yagyū Munenori taught swordsmanship to the Tokugawa shoguns, and a Zen monk wrote down for him where a fighter's mind should be when a blade is coming at it. Takuan Sōhō's answer was: nowhere. A mind fixed on the opponent's sword, on its own sword or on the timing stops there, and he gave that stopping a Buddhist name, the affliction of abiding in ignorance. A mind that rests on nothing is free to go anywhere. Look at one leaf of a tree, he wrote, and the other leaves are as good as absent; look at none, and the whole tree is there at once. He turned the same test on a technique taught to fighters and meditators alike, holding the mind just below the navel, and ranked it low, because a mind told to stay in one place is held by the instruction. No original of his text, The Mysterious Record of Immovable Wisdom, survives, and its date is uncertain.
Takuan came to it from the centre of Japanese Zen. His father served the Yamana, the lords of Tajima, whose house fell to the forces of Oda Nobunaga when the boy was eight; at ten he entered a temple as a novice. He trained at Daitoku-ji in Kyoto, the monastery Shūhō Myōchō had founded three centuries earlier, and was made its abbot in 1609, a post he left after three days. Later he turned down an invitation from Toyotomi Hideyori, the heir of Japan's late ruler. In 1638 he declined the title of National Master offered by the retired emperor Go-Mizunoo and asked that it be given instead, posthumously, to Tettō Gikō, Shūhō's disciple and successor at Daitoku-ji. He also wrote the founder's life: a chronicle, finished in 1617, that put a date to every incident, some of them taken from documents and others, in the judgement of the historian Kenneth Kraft, beyond verification.
The shogunate gave him his hardest years. Its new laws required Edo's approval for appointments at Daitoku-ji, and in 1627 it annulled the purple robes that Go-Mizunoo, then emperor, had granted to senior monks without consulting it. Takuan helped lead the protest of Daitoku-ji and Myōshin-ji and drafted its petition. In 1629 he was tried at Edo and banished to Kaminoyama in the northern province of Dewa, where the local lord, Toki Yorioki, built him a hermitage. A general pardon followed in 1632, after the death of the retired shogun Hidetada, and Munenori was among those who worked for it. Munenori and the monk Tenkai, an adviser to the shoguns, then brought Takuan before the third shogun, Iemitsu, who called him to Edo to lecture, installed him in 1639 as first abbot of Tōkai-ji, a temple he had built for him in Shinagawa, and in 1641 restored the rights the two monasteries had lost.
The martial arts adopted the book. Imamura Yoshio, a historian of the Yagyū family, called it the first work to explain the inner meaning of the martial way through Zen, and Eugen Herrigel's Zen in the Art of Archery carried part of it to Western readers. The scholar Brian Victoria, in Zen at War, argued that Takuan's teaching of an empty opponent licensed killing and broke the Buddhist precept against it, a reading that others contest.
He died in Edo, and the tradition says that before he put down the brush he wrote a single character, yume, "dream". Both Iemitsu and Go-Mizunoo had asked him to name an heir to his teaching, and he named none; his last instructions called anyone who claimed to be his heir a thief of the Dharma. Peter Haskel, a translator of his writings, reads this as Takuan's view that the mind of Zen exists whenever a practitioner realises it, with or without a teacher's sanction.