Neo-Confucianism, with the aim of keeping clear the innate luminous virtue [true goodness] of all men throughout the empire[1] and thus establishing social harmony , was a complex ethical political system. governing society in late Ming China. Adopting this philosophy as ideological legitimacy, the Choson Kingdom and the Tokugawa shogunate applied it in different contexts due to their governmental structure and cultural context. However, they both inherited the main elements of the philosophy: the notion of a universal principle encouraging people to behave well, five virtues[2], self-cultivation and five hierarchical relationships of society[3]. Through traditions, rituals, laws, publications, educational institutions and more, this philosophy permeated the life of the Choson court and the Tokugawa samurai. Yet, as was the case in Ming China, the governments of these two kingdoms could not always “control the interests of their people”[4] and make them adhere to the ideology. Complex life situations as well as the fallibility of human nature making people incapable of always leading an intellectual, moral and distant life[5] have led to gaps between philosophy and its experiences. The court of the kingdom of Choson, where the very orthodoxy of the state should be practiced. at its highest level, was ironically also a refuge for its conflicts. The extended royal family lived together at court and exercised filial piety among all: devotion among all members of the family, including mourning for the deceased and visiting ancestral tombs. Lady Hyegyong, in her memoirs, noted many examples of true filial devotion within the royal family; that of King Yongjo himself preparing medicine for his sick mother-in-law, Dowager Queen Inwon[6], and the sa...... middle of paper......indulging in learning and to frugality as Mori Yoshiki did. In order to get what he wanted from others, he could even violate the principle of being true to oneself by imitating hara-kiri. Yet he later regretted the outcome of his easy life as he reflected on his old age and was also surprised by the discoveries that throughout history there were many who acted like him and made mistakes. Human beings are a mystery to themselves. By law, by ideology, we still cannot be governed. Neo-Confucianism, with its practical appeal, appealed to governments and was implemented. However, as she claims, philosophy could not be practiced naturally as it should be. Some parts were accepted, others were not. People were always free on their own. However, Neo-Confucianism could shape people's lives and contribute to human civilization..