Yi Hwang
Yun Doo-su (; 1533–1601) was a Korean scholar-official of the Joseon Kingdom. Politician, Poet, Writer, and scholar, he was a follower of Yi Hwang school among Westerners (Hangul: 서인, Korean: Seoin). Among many other official positions, he served as Chief State Councillor during the reign of King Seonjo. His pen name was Oheum (오음, 梧陰), courtesy name was Jaang (자앙, 子仰).