本文以南塘韓元震的性論和心論為中心，分析了人物性異論的理論結構及其意義。在性論當中，韓元震提出「性三層說」，論證了人物性異論的妥當性。韓元震認為，在「超形氣」的層面上，人物相同；在「因氣質」的層面上，人人相同而人物相異。在心論當中，韓元震將「心」分為「虛靈」和「氣稟」主張聖人和凡人的區別不在於「心之虛靈」而在於「心之氣稟」之上。因此，韓元震強調改善氣質工夫的優先性，提出若通過變化「心之氣質」而恢復「心之虛靈」則心就能夠引導血氣和形質通往正確的方向。總而言之，韓元震從性論和心論這兩方面闡述了人之所以與物不同的原因。首先，從性論而言，只有人才真實地稟受了「五常」，並以仁義禮智為性。其次，從心論上來看，只有人才能夠克服天生氣質的限制，以完成道德人格。

This paper is to deliberate the structure and meaning of Han Won-jin's theory on the difference of nature between human being and other living things centered in theory of human nature and theory of human mind. In theory of human nature, Han Won-jin raised ＂Sŏngsamch 'ŭngsŏl＂ and protested the difference of nature between human being and other living things. Han Won-jin viewed that human nature and things nature are same ＂beyond figures and energies＂ but different ＂in terms of physical constraints＂. According to Han Won-jin, only human being is born with entire ＂Kijil＂ (temper) and takes Osang as his/her nature. Next, in theory of human mind, Han Won-jin explained mind in the two levels such as ＂Horyong＂ (essence) and ＂Kijil＂ (temper). According to Han Won-jin, in terms of ＂Horyong＂ of mind, saint and ordinary person have same mind but in terms of ＂Kijil＂ of mind, they are different. However, the ＂Kijil＂ of mind can be overcome by training. Through training to change one's own ＂Kijil＂, anyone can reach to saint's level. Consequently, Han Won-jin demonstrated human nature and things nature in the following two levels. First, only human being has entire ＂Osang＂. Second, only human being can change his/her innate ＂Kijil＂ (temper).