This manuscript reexamines how the Kumamoto 熊本 Jitsugaku 實學 (kor. Silhak, Realist School of Confucianism) School embraced Toegye’s philosophy. For this purpose it focuses on the thoughts of Ōtsuka Taiya 大塚退野 (1678-1750), precursor of this school, who in the Japanese history of thought was the person presumably most fascinated with the philosophy and personality of Yi Toegye 李退溪 (1501-1570), adds the related commentaries of Yokoi Shōnan 橫井小楠 (1809-1869) and Motoda Nagazane 元田永孚 (1818-1891), which later inherited Taiya’s philosophy, and thus subsequently tries to find to a desirable blueprint for the future Korean-Japanese relations. In the history of thought in East Asian between the 17th and the 18th century, Taiya chose the orthodox Neo-Confucianism of Zhu Xi and Toegye from the spectrum of the various ideas in the Edo period history of thoughts and became deeply absorbed in it, which later when scholars from the same region who succeeded him sought the foundation for a new philosophy they called Jitsugaku 實學 constituted one important axis among the ideas in the reformation period towards the end of the Tokugawa shogunate 幕末惟新期. To verify that the main source of contact with and influence from Toegye’s philosophy for the scholars of the Kumamoto Jitsugaku School came from the “study of the mind” (kor. Simhak 心學 or Simsulgongbu 心術工夫), in this manuscript we will examine commentaries that these scholars beginning with Taiya made on Yi Toegye as well as the critical statements about Ogyū Sorai 荻生徂徠 (1666-1728) and Yamazaki Ansai 山崎闇齋 (1619-1682). The criticism of Sorai and Ansai also bears the functional significance to highlight the ideological peculiarities and position of Toegye and the Kumamoto Jitsugaku School in the Japanese history of thought. In conclusion, this links the importance that is attached to the “study of the mind” to the “discourse on the unity of heaven and man 天人合一論”, and points out that the desirable blueprint of the future between Korea and Japan, which Toegye and the scholars of Kumamoto Jitsugaku School that succeeded him were implying, could be created when approaching other states with the extended line of thoughts from a policy of genuine “benevolence 仁” that cares for the real life of the citizens and not with a “truthful mind”, the “principle of benevolence and righteousness of heaven and earth 天地仁義の大道” or the fictitious honor of the “state” and rivalry.
2. A Perspective on the Influence of Toegye’s Philosophy: Motoda Nagazane’s “Imperial Rescript on Education”
3. Rearrangement of Ōtsuka Taiya’s Reception of Toegye’s Philosophy
4. The Acceptance of Toegye’s Philosophy in the Jitsugaku School of Kumamoto: “Study of the Mind” and Critical Perspectives in the History of Edo-Confucianism
5. Instead of a Conclusion: The Discourse on the “Identity of Heaven and Man” and a Suggestion for the Korean-Japanese Relationship