Cui Yuan (Han dynasty)
Cui Yuan (; 77–142 or 78–143 AD), courtesy name Ziyu, was a Chinese military officer, mathematician, calligrapher, poet, politician, and temporary fugitive of the Han Dynasty (202 BC–220 AD) in China. He is known for his many written works, although in political life he became involved in court intrigues which damaged his career. Life. Cui Yuan was born in the Lecheng Commandery (renamed Anping in 122) in what is now modern Hebei province. He was the son of Cui Yin, who died while Yuan was in his teens. After years of study, he ventured to the Han  capital at Luoyang when he was eighteen. There he studied under Jia Kui and befriended notable persons such as the scholar and commentator Ma Rong (79–166) and the prolific inventor, mathematician, scientist, and official Zhang Heng (78–139). Cui gained a reputation as a mathematician with his work on reforming the Chinese calendar and as a scholar following his commentary on the "I Ching".