明中葉羅欽順曾以書信與王陽明弟子歐陽崇一討論良知之旨。歐陽崇一認為良知具有創生規範之功能，故可稱之為實體；羅欽順則以良知僅屬心之經驗作用，不可作為客觀之理規範，故非實體。此次論爭實際上反映良知可否取代程朱理學之理概念的問題，其討論方法頗具有啟發性。 本文說明王陽明之良知作為本體論意義之實體的涵義，與羅欽順之實體觀的理論基礎。另參照朱子與湛甘泉、王廷相、戴震諸人有關實體之不同用法，探討羅欽順與歐陽崇一之論爭在思想史上之意義。

Lo Ch'in-shun discussed with Wang Yang-ming's disciple, Ou-yang Ch'ung-i, whether conscience could be regarded as an ontological reality by corresponding with each other at the middle of the Ming Dynasty. Ou-yang maintained that conscience could create and determine right moral act by itself and consequently it was reasonable to assure that conscience was an ontological reality. As to Lo, conscience was nothing but some empirical function of mind and therefore it shoud not be regarded as an objective norm. In fact, from this debate came up a question, that is whether conscience could take the place of Ch'eng-Chu School's conception of 「Li」 (理) or not. This paper, in the first place, tries to make clear why conscience could be regarded as an ontological reality in Wang Yang-ming's philosophy. Second, the background of Lo's opposite viewpoints will be explained . Third, by referring to the different usage of reality or ontological reality put forword by some prominent scholars such as Chu Hsi (朱熹), Jann Kan-ch'uan (湛甘泉), Wang T'ing-hsiang (王廷相) and Tai Chen (戴震) in their texts, reality can be understood in several ways. Today, in exploring Confucian reality, especially in terms of ontological reality it is important for us to evaluate this debate as well as its subject and method.