Sadaebu (Bureaucratic brackets), who accepted Seongrihak (Neo-Confucianism) for the late period of Goryeo, did cope with a social change and the system disturbance through Kyong.
Kwon principle, and the purpose of this study was to try to grasp what this means in relation to a matter of the system.
Sadaebu (Bureaucratic brackets) for the late period of Goryeo, did accept Jujahak, which is Gwanhak, focusing on "Saseojipju" by Juja, and did accept Kyong' Kwon principle of Confucianism. In terms of Confucianism, Kyong is a rule of natural phenomenon with the meaning of Sang as the supreme principle, which is universally reasonable and eternal, and the highest rule of constancy, which becomes the basis of human existence and the reason. On the other hand, Kwon means the transfigured morality as to the specific situation that Kyong fails to reach. It can be said to imply the use after transfiguring in line with a situation without losing the basic spirit of courtesy. Kyong and Kwon originate from the logic of temporary expedient by "Mencius." It is said that rescuing by grasping brother's wife who was drowning is an unavoidable action under special circumstances. Juja admitted Kwon principle but said that only being Daeseong (Big saint) and Daehyeon (Big sage) can perform Kwon principle without losing its rightness.
Sadaebu (Bureaucratic brackets) for the late period of Goryeo, who accepted Seongrihak (Neo-Confucianism), had known the logic of Kyong and Kwon, and did apply this to a social change of that time. That time was the transition period of Yuan and Ming,. was when Japanese pirates and Honggeonjeok invaded, and was when agricultural society of udans was collapsed and farmers' production foundation was destroyed. Sadaebu (Bureaucratic brackets) strived to put importance to Kwon principle and to maintain the system of Goryeo dynasty, aiming to break through this.
Ha Ryun, who learned Seongrihak (Neo-Confucianism), did intend to solve a diplomatic issue with Ming, through Kwon principle. When Yodongdosa sent Yeojin, Cheonho and Baekpapasan out for Uwangneongan and they reached Bukcheongju, Kim Deuk-gyeong, who received the order of a cabal, did kill these persons. At this time, Ming tried to send Kim Deuk-gyeong in custody, and as soon as Kim Deuk-gyeong said that he will tell the truth, the royal court killed Kim Deuk-gyeong by camouflaging as a thief, and Ha Ryun rationalized this as Kwon principle. It is being utilized as the means of a rough make shift, not as Kyong and Kwon principle that Confucianism originally says.
Sadaebu (Bureaucratic brackets) like Yi Saek, who accepted Seongrihak (Neo-Confucianism) for the late period of Coryea, did mention the inevitability of a real situation aiming to break through the system change and the critical condition, and this is resulted from taking advantage of the logic of a rough make shift like Kwon principle. Rather than seeking for theoretically Confucian ideology like Kyong and Sang, it was what considered a reasonable method for it under the urgent situation of actuality, and the logic of circumstances for reality. This implies that it admitted the past governing relationship no matter what the logic is, and assumed the existing governing order. Sadaebu (Bureaucratic brackets) including Yi Saek, who aims to keep the Goryeo monarchy, did accept Seongrihak (Neo-Confucianism) and at the same time, had priority over convenience suitable for reality and the inevitability of actuality.
So to speak, Yi Saek and his pupil Ha Ryun, who accepted Seongrihak (Neo-Confucianism) for the late period of Goryeo, did understand Kyong(Sang) and Kwon principle and did utilize Kwon principle for supporting the past system and political power, amid emphasizing on the inevitability of a real situation.