本文擬對南朝佛性說與神不滅思想交涉的一個具體例證進行分析。《涅槃經》原即主張「眾生」為「正因」，因為眾生「相續不斷」，是將來能成佛之物，而緣慮之「心」更被視為此相續不斷過程的核心。莊嚴寺僧旻的「眾生正因」，或定林寺僧柔、開善寺智藏的「六法正因」之說，都謹守著此一立場，只是他們更進一步強調「緣慮心」或「神明」相續的重要性；主張本有、始有相續一體的「本有於當」之說，即由此衍生。沈約的神不滅思想，即以此「眾生正因」之說為理論基礎。他主張眾生的「知性」 、 「受知之分」相續不斷，是輪迴生死或修行成佛的連續同一體。此一相續不斷的連續體獨立於善惡之「念」所引發的因緣生死之外，但卻又是因果輪過的根據。此一發展歷程可讓我們對「神不滅」如何轉向「佛性」思想有更清楚的認識。

This paper will look at a concrete example of the interplay during the Southern Dynasties between the Buddha-nature ( buddhadhātu ) theories and the notion of an "immortal soul". According to the Mahāparinirvāna-Sūtra, sentient beings are the "direct cause of buddha-nature" because they continue without an end in samsāra and are able to become Buddha in the future. Likewise, the continuity of mind ( citta ) was considered central to the continuation of sentiment beings. The theory of zhongsheng zhengyin advocated by Seng Min of the Zhuangyan Temple and the theory liufa zhengyin advocated by Seng Rou of the Dinglin Temple and Zhi Cang of the Kaishan Tample, basically followed this doctrine, although the essentiality of the continuous mind or shenming was given a stronger emphasis. This was also the foundation of their famous theory of "benyou yudang", which suggests the union of the a priori and the a posteriori in buddha-nature. Shen Yue built on this line of thought in his theory of immortal soul. He contended that the intellectuality, or the receptacle for wisdom, possessed by sentient beings is continuous and maintains its self-identity throughout the process of samsāra and the path towards enlightenment. This mental continuum is the source of samsāra, but exists independently from the chain of death and rebirth caused by good or evil thoughts. In the transition from the Mahāparinirvāna-Sūtra to the theory of zhongsheng zhengyin, and then to the thought of Shen Yue, we can see how the theory of buddha-nature affected and changed the way people thought about the immortal soul, and eventually replaced it.