Gidō Shūshin 義堂周信 (1325–1388) — Late-Nanbokuchō / early-Muromachi Japanese Rinzai-Zen master and one of the two preeminent Gozan-literature masters of the period (with his contemporary Zekkai Chūshin 絕海中津). Self-styled Kūge Dōjin 空華道人 (“Empty-Flower Way-Person”). Lineage: dharma-heir of 夢窓疎石 Musō Soseki.
Born 1325 in Tosa Province (modern Kōchi). Took the tonsure under Musō; studied at Musō’s various Kyoto and Kamakura temples. Active at Engaku-ji 圓覺寺, Nanzen-ji 南禪寺, Kennin-ji 建仁寺, and other Five-Mountain monasteries. A close adviser to the third Ashikaga Shōgun Yoshimitsu 義滿, who frequently consulted him on Zen and on the Gozan literary tradition.
Gidō stands as one of the two principal Gozan literature writers — his collected works are the Kūge nichiyō kufū ryakushū 空華日用工夫略集 (a literary diary) and the Kūge shū 空華集 (his collected verse and prose). The diary records his daily literary studies, his conversations with the shōgun, and his readings — a unique primary source for the Muromachi-period high-cultural Zen establishment.
His Recorded Sayings — Gidō Oshō goroku 義堂和尚語錄 (KR6t0262, T80n2556) — four fascicles, compiled by his disciple Chūshin 中圓 and others. Listed in Nihon Bukkyō zensho 日佛 vol. 108, p. 317.
Source: standard Japanese Rinzai-Zen biographical sources; Pollack, The Fracture of Meaning (1986); Tsuji Zennosuke 辻善之助, Nihon Bukkyō shi: Chūsei-hen 日本佛教史·中世篇 (1944).