 The nineteenth century was a time of transformation in East Asia, particularly in Korea, and Confucian scholars were still eager to validate their discourse, even if it meant persecuting rivals: between 1866 and 1871, between 8,000 and 10,000 Catholics, men, women and children were tortured and executed by Confucian authorities. Choi Min-Hong (1980:191–217) notes the re-emergence of philosophers interested in Principle in the nineteenth century, many who had been linked with the Namin faction, hence, proponents of the T’oegye’s metaphysical ideas. This included Ki Chŏngjin (1798–1876) and Yi Hangno (1792–1868), the latter who considered Principle to be the basic substance of the universe, and “something spiritual” (1980: 194). Ki Chŏngjin, who again returned to study the writings of Zhu Xi, also re-engaged with studying sage learning and “researching the Classics”. He regarded Principle as a sort of spiritual Supreme Ultimate, which then produced yin and yang (and the material force)—in other words, Principle preceded ki, and this Principle was reflected differently in men and animals (Choi M.-H. 1980: 196–198). Yi Chin-sang (1818–1885) also considered Principle as preceding ki, but also as that which generated it, therefore, self-cultivation lay in the study of the mind and not in knowing external things due to man’s “Heaven-bestowed cognitive powers” which depended on “transcendental Li [Principle]”. Such idealistic ideas were hardly needed at a time when society was in such a state of disarray, already foreboded in the writings of Tasan.