「陰陽論的思維」與「理氣論的思維」，是東亞思想史中基礎卻極具影響力的思考方式。陰陽論的思維，是在先秦時期通透《周易》而集大成，不僅儒家，道家、墨家、法家等學派也共享這一內容。相對而言，理氣論的思維則是宋代通過朱子學而確立的思考方式。朱子為了批判道家、墨家、法家與佛教等所謂的「異端」，而建立起理氣論這一理論體系的。理氣論的思維雖然不如陰陽論的思維具普遍性，但在崇尚朱子學的朝鮮時代，成為一種非常有力的思考方式。陰陽論的思維與理氣論的思維既有共通之處，也有差異，兩者的共通點在於：無論是「陰與陽」還是「理與氣」，都是以一對概念來規範萬事萬物並加以進行說明。然而，陰陽論與理氣論在解釋兩兩相對的關係時，卻有所不同。陰與陽皆屬於形而下者，兩者之間存在尊卑的位階（不易，陽尊陰卑），並且互為對偶、相互成就（交易，陰陽對待），又彼此循環（變易，陰陽循環），這些是關於陰與陽的說明。反之，「理」與「氣」則區分為「形而上者與形而下者」，形而上者既無形體也無作用，而形而下者則具有形體並有作用。無形無為的「理」是有形有為之「氣」的理念性標準，而有形有為的「氣」則是實現無形無為之「理」的工具，這是關於理與氣的說明。從這樣的觀點出發，本文首先比較了陰陽論的思維與理氣論的思維，接著從「陰陽論思維與理氣論思維的對立」這一觀點，探討朝鮮末期的心說論爭。

The modes of thinking based on Yin-Yang theory and Li-Qi theory are both highly influential frameworks in the intellectual history of East Asia. Yin-Yang thinking was systematized during the pre-Qin period through the Book of Changes (周易 Zhouyi) and was embraced by Confucianism, Daoism, Mohism, and Legalism. In contrast, Li-Qi thinking was established during the Song dynasty within Neo-Confucianism, particularly in the philosophy of Zhu Xi, who formulated this system of thought as a theoretical framework to critique what he regarded as heretical doctrines, including Daoism, Mohism, Legalism, and Buddhism. While Li-Qi thinking did not attain the widespread universality as Yin-Yang thinking, it became the dominant intellectual framework in the Joseon dynasty, in which Zhu Xi's philosophy was highly revered. Although Yin-Yang and Li-Qi thinking share certain similarities, they also exhibit key differences. Both categorize all things into dualistic conceptual pairs - "Yin and Yang" or "Li and Qi" - to explain the nature of reality. However, each theory conceptualizes the relationship between these paired elements differently. In Yin-Yang theory, both Yin and Yang belong to the physical domain or "below form",[形而下 xingerxia].Their relationship is characterized by a hierarchical structure (immutability: Yang is honored over Yin), dynamic complementarity (interaction: Yin and Yang mutually generate and complete each other), and cyclic transformation (change: Yin and Yang alternate and transform in endless rhythm). In Li-Qi theory, Li and Qi correspond respectively to the metaphysical and physical. Li is formless and inactive, serving as the ideal norm for Qi, which is the instrumental medium through which Li is realized. This paper first compares these two modes of thinking-Yin-Yang and Li-Qi-and then analyzes the "Simseol debate (Debate on the nature of the mind)" in the late Joseon dynasty, exploring the tension between these two intellectual paradigms.