Namin scholar of the Seongho school learned in mathematics and astronomy, favored by King Jeongjo and Minister of Works; pen names Geumdae and Jeongheon
| Life | 1742 ~ 1801 |
| Era | 조선 후기 |
| Clan | 여주 이씨 |
Yi Ga-hwan (1742-1801) was a late-Joseon scholar-official of the Yeoju Yi clan, courtesy name Jeongjo and pen names Geumdae and Jeongheon. His father was the writer Yi Yong-hyu and his grand-uncle Yi Ik, whose school he carried on. His nephew Yi Seung-hun (of the Pyeongchang Yi) is known as Korea's first baptized Catholic.
He became a jinsa in 1771 and passed the civil examination in 1777, serving as Director of the Seonggyungwan, Governor of Gaeseong and Minister of Works. King Jeongjo favored him as a successor to Chae Je-gong as leader of the Namin and called him "Scholar Jeong". He calculated solar and lunar eclipses and the angle between the ecliptic and equator, and was noted for prose and calligraphy.
His relation to Catholicism was complicated: after debating Yi Byeok he read Catholic books, but after the 1791 persecution he wrote a hymn-like verse warning against it, and after 1795 was demoted to Magistrate of Chungju. After Jeongjo's death he became a prime target of the Noron Byeokpa in the 1801 persecution, was jailed in February and died in prison on March 24. He is said to have lamented that mathematics in Korea would die with him.
King Jeongjo prized his learning and is said to have considered him for chief minister, and Jeong Yak-yong remarked that one might suspect him of being a spirit. Works such as the Geumdae Simunchobi survive, but the Geumdaegwanjip does not.
After Sunjo's accession, under the regency of Queen Dowager Jeongsun, the Noron Byeokpa purged the Namin and Sipa in the name of banning heterodoxy. Yi Ga-hwan was singled out as the figure they most wished to remove and died in prison in 1801; his body is said to have been left in the street.
With no son he is said to have adopted Yi Jae-jeok.