Jeong Yakyong / Jung Yak-Yong, often simply known as ‘Dasan’, was one of the greatest thinkers in the later Joseon dynasty period, wrote highly influential books about philosophy, science and theories of government, held significant administrative positions, and was noted as a poet. He was a close confidant of King Jeongjo and his philosophical position is often identified with the Silhak school, and his concerns are better seen as explorations of Neo-Confucian themes.
Jeong was born on 5 August 1762 in Gwangju-gun, Gyeonggi-do and died on 7 April 1836 in there too. He spent 18 years in exile in Gangjin, South Jeolla Province, from 1801 until 1818, on account of his membership of the Southerners faction, and also because of the Catholic faith of his elder brother. Korean Catholics sometimes claim that Jeong was baptized with the name John Baptist, but there is no documentary proof of this. He was came from Naju Jeong clan.
At birth he was given the courtesy title Gwi’nong, and later he was also known by the ja Miyong and Songbu 美庸; among his ho were Saam, Tagong, Taesu, Jahadoin, Cheolmasanin, Dasan, Yeoyudang.