本文主要針農巖金昌協與三淵金昌翕所提出的人、物性同論進行研究。金昌協提出了理氣說、四端七情說、知覺說、未發說等諸多學說，奠定了展開人、物性同論的洛學之理論平臺。金昌翕在繼承金昌協學說的基礎上，又進一步確立了擁護人、物性同論的洛學之學問方向。兩兄弟關於人性與物性的問題從如何在現實中縮小氣的地位，強化理的地位的問題意識上出發，努力找尋性善這一人間道德性之根源。因而，他們對於其根源，不是在氣中，而是在獨自發用的理中找尋到的。也因此，他們主張了偏全之性只是依靠氣質而受到制約的性而已，並非性的真面目，性的真面目在理，故而，人性與物性是同一的。總之，金昌協與金昌翕所提出的人、物性同論，其最終目的在於，即使無法完全排除氣質之影響，我們也能在現有的任何狀況下，得以確認並擴大人間道德性之根源，並通過此根源，達到獨立地、能動地體現人間真面目的境地。

This essay is the study for “the theory of whether human nature and things nature are same or different” (Inmulsŏngdongiron) of Nongam Kim Ch’ang-hyŏp and Samnyŏn Kim Ch’ang-hŭp. Kim Ch’ang-hyŏp established the theoretical foundation of Na-k’ak on the basis of his Neo-Confucianism views. Kim Ch’ang-hŭp established an academic direction of Na-k’ak on the basis of Kim Chang-hop’s such views. By the way, the philosophical starting point of two brother is seen as li and ki. Because they are trying to lower position of the ki, at the same time, enhance position of the li in the real world. Based on this viewpoint, they discussed the problem of human nature and animal nature in the purpose for finding “the roots of human morality”. And so, they looked for the roots in the li. Of course, this li doesn’t leave ki, but doesn’t receive an effect by ki in the real world. Therefore, they believed li to be the original nature of all beings and identical to original nature and the Five Virtues. Consequently, they advocated that “human and non-human beings share the same nature” because the true appearance of “nature” is li. Their opinion that the Five Virtues were inherent in all beings led to “the conclusion that human and non-human beings had possessed an identical moral original nature”. After all, the final goal of their opinion is that we can never escape from the “temperament”, but regardless of that, can expand the roots of human morality, and can manifest the true appearance of subjective and proactive human, depending on the given situation.