心性思想是漢傳佛教（尤其是中國禪宗）的核心思想。禪宗的創立，起於 初祖菩提達摩，而成於六祖慧能。馬祖道一（709-788）得法於南嶽懷讓，南 嶽懷讓又得法於曹溪六祖慧能。馬祖的禪法依據不同根機的眾生而分別方便教 化，在發揚光大六祖禪法思想的同時，也加以創新發展，從而開創了對後世習 禪者影響深遠的洪州宗。本文以體用觀和心性論的範疇，論述馬祖禪法思想的 三個方面：一、心性（佛性）為體的思想；二、般若為用的思想；三、心性 （佛性）與般若體用不二的思想。馬祖所提出「平常心是道、即心即佛、非心 非佛」等新觀念，發展了禪宗的心性思想，儼然成為洪州宗宗風的象徵，同 時，本文也釐清了宗密對於馬祖禪法思想的論述，以便大家形成一個較客觀的 認知。

Mind-Nature is the core idea of Han Buddhism, especially Chinese Chan (Zen). Chan was founded by Bodhidharma and then well developed by the Sixth Ancestor, Huineng. Traditionally, Mazu Daoyi (709-788) is depicted as a successor in the lineage of Huineng, since his teacher Nanyue Huairang is regarded as a student and successor of Huineng. Mazu’s teaching of Chan were given to the sentient beings according to their capability. While carrying forward the Sixth Ancestor’s thought of Chan, Mazu also developed it innovatively. Thus, he founded Hongzhou school, which has a profound influence on later generations of Chan practitioners. This paper discusses three aspects of Mazu’s thought of Chan within the frameworks of Essence-Function (Tiyong) and Mind-Nature (Xinxing). It intends to explore the three new ideas of Mind-Nature in Hongzhou school proposed by Mazu: “the truth is in the mind, the truth is in the Buddha” and its corollary－“the truth is not in the mind, the truth is not in the Buddha”, and finally “the calm mind is the Dao”. He developed the thought of Mind-Nature in Chan school, which has become a characteristic of Hongzhou school. Nevertheless, Mazu Daoyi’s Chan thinking faithfully inherits the relevant Chan thought of Huineng. Therefore, the Hongzhou school is considered to be an orthodox branch of Chan propagated by Huineng and his followers.