Gonso was a Sanron sect priest (born in 754 and passed away in June 25, 827) in the latter Nara period and the former Heian period. His secular name was Hata clan. He was from Takaichi County, Yamato Province. He was also called Iwabuchi Jonin (a holy priest Iwabuchi).
Gonso studied San-lun Teachings under Shinrei and Zengi at Daian-ji Temple, and was chosen as Senzo Dosha (entering the Buddhist priesthood chosen from thousands of priests). Gonso worked as the chief priest of the service at a dedication ceremony at Konponchudo on Mt. Hiei. In 796, at Iwabuchi-dera Temple located at the foot of Mt. Takamado, he started Hokke hakko (ceremonial series of eight lectures on the eight scrolls of the Lotus Sutra) for the repose of the soul of Eiko, who had been in the same school. In 813, Gonso argued the Hosso teachings down at Daigoku-den Saisho-ko and was designated as Risshi (the third rank of priest following Sojo and Sozu). Gonso worked as betto (chief administrator) of Gufuku-ji Temple (also known as Kawara-ji Temple) and Sai-ji Temple, which was under construction at that time, and became Daisozu (the upper Buddhist priests in the second highest position) in 826. Gonso also showed understanding for new sects, the Tendai sect established by Saicho and the Shingon sect established by Kukai. He was raised to Sojo in Soi (rank of Buddhist priest) after his death.