Late-Heian-period Japanese Shingon monk and the principal reformer of post-Kūkai Shingon doctrine. Founder of the Shingi Shingon 新義真言 (“New-Doctrine Shingon”) sub-school, distinct from the older Kogi Shingon 古義真言 (“Old-Doctrine Shingon”) of the Mount Kōya 高野山 main lineage. Japanese name Kakuban 覺鑁; posthumous title Kōgyō Daishi 興教大師 (“Great Master of Doctrinal Restoration”). Born 1095 in Hizen Province (modern Kyushu); died 1144 at Negoro-ji.
He took monastic ordination at Mount Kōya in 1107 and pursued an extended scholarly programme combining the Shingon Esoteric tradition with the Pure Land 淨土 amitābha-faith of the contemporary Tendai-Heian devotional movement. His doctrinal innovation — the integration of Mahāvairocana 大日 (the cosmic Esoteric-Buddha) with Amitābha 阿彌陀 (the Pure-Land Buddha) — was developed at length in his major treatise the Mitsugon-jōdo ryakkan 密嚴淨土略觀 (Brief Contemplation of the Mitsugon Pure Land) and became foundational for the subsequent Japanese Esoteric-Pure-Land synthesis.
His doctrinal innovations met opposition from the conservative Mount Kōya establishment, and in 1140 he and his disciples were forced from Kōyasan in the so-called Kōya-Negoro division 高野根來分派. He removed to Negoro-ji 根來寺 in Kii Province (modern Wakayama), which became the principal center of the Shingi Shingon school. After his death in 1144 the Negoro-ji line continued to develop in opposition to the Kōyasan main line; the eventual Tokugawa-era reformulation under Senjo 専譽 and Genyū 玄宥 produced the two Shingi-Shingon sub-schools (Chizan-ha 智山派 and Buzan-ha 豐山派) that continue today.
He was posthumously titled Kōgyō Daishi in 1690 by Emperor Higashiyama, a long-delayed canonical recognition reflecting his importance to the Shingon-school doctrinal tradition. His principal surviving Lotus work in the Taishō is KR6d0043 Hokekyō hishaku 法華經祕釋 (T2191).
Source: standard Japanese Shingi-Shingon biographical sources; Inaya Yūsen 稲谷裕宣, Kakuban no kenkyū 覺鑁の研究, Kōyasan: Kōyasan Daigaku, 1969; van der Veere, Henny, A Study into the Thought of Kōgyō Daishi Kakuban, Leiden: Hotei, 2000.