Tasan Chŏng Yagyong (1762–1836) is one of the most creative thinkers Korea has ever produced, one of the country’s first Christians, and a leading scholar in Confucian philosophy. Born in a staunchly Neo-Confucian society, in his early twenties he encountered writings by Catholic missionaries in China and was fascinated. However, when he later learned that the Catholic Church condemned the Confucian practice of placing a spirit tablet on a family altar to honor past generations, he left th...