IKKYŪ SŌJUN (1394–1481) was a poet, calligrapher, Zen eccentric, and revitalizer of the Daitokuji line of Rinzai Zen. Ikkyū was likely, as legend suggests, the unrecognized son of the hundredth emperor of Japan, Gokomatsu (1377–1433; r. 1392–1412), by a rather low-ranking court lady. At an early age, perhaps for lack of any other option, his mother placed him in the Gozan temple of Ankokuji, in Kyoto. He spent the rest of his childhood in Ankokuji and in Tenryūji, yet another Gozan establishment. A quick student, Ikkyū was precocious in both scriptural studies and in the literary arts that had become a focus of the aesthetically oriented Gozan movement.

In 1410 Ikkyū left Tenryūji to live in the streetside hermitage of the eremetic monk Kenʾō Sōi (d. 1414). Kenʾō belonged to the Daitokuji-Myōshinji lineage of Rinzai. Because...