朱子在理氣論的存有學基礎上主張「心統性情」的心性論。他在中和新舊說的參究上對於成德工夫是否存在著未發工夫進行一番推敲並數異其說。「心」是朱子德行論最為核心且精彩的概念。研究學者素來以朱子對於張橫渠「氣質之性」的攝取，並以其「心者氣之精爽」、「以虛靈明覺言心」等主張，以對照於陸象山之主「本心」與「心即理」。據此，當代大儒牟宗三先生認定朱子即在「理氣二分」的存有論上建立起了「心性情三分」的心性理論系統，並判定其中「性」是在理的.層面，是形上之理，而「心」與「情」則屬於「氣」，屬形下的氣稟，即所謂「氣心」。筆者企圖從各個方面證明朱子之主「心統性情」的「心」作為一個道德主體，雖不完全相同於陸象山之單純主形上之「本心」，但亦不能因此就被判定為「氣心」。依此，筆者進而反省以「本心」與「氣心」形上形下二元對立的概念框架來論述人性之道德主體性的侷限性，並尋求其它詮釋形式的可能性。

For Zhuxi's moral thought, Modern Confucianism research have also been continuing efforts and have achieved fruitful results. The importance of Zhuxi's moral theory can be appreciated by scholars, but the modern moral significance has not yet been made a further analysis. However, Zhuxi's theory of virtue is a modern interpretation and positioning caused great academic debates.According to Zhuxi, Man is a combination of Principle (理) and Material Force (氣), and the purpose of moral cultivation is to carry out Principle, by overcoming any hindrance from Material Force. Therefore, this article will concentrate to investigate the meaning of moral thought of Zhuxi's 'xin tong xing qing' (心統性情), and the significance of Zhuxi's theory of Mind (心) may be revealed through the study of it.According to Zhuxi, Mind includes Nature (性) and Feeling (情). Nature is substance (體), Feelings are functions (用). There is only one Mind, but there are two levers of the content of Mind: the Original Mind (本心) on the transcendental aproach and the Physical Mind (氣心) on the empirical approach.