「從『性善』到『性本善』」，基本理論是建立在孟子「性善」說的蘊義不同於以朱熹為主的「人性本善」說之上的。此一撼動一般認知的議題，若僅討論《孟子》文本以及朱熹對之的注解，易淪於各說各話之境。因此，外循他證以佐據「性善」到「性本善」乃是有一明確發展歷程，無疑是較能說服他人之方。誠如朱伯崑先生指出：「人性本善的說法，始於唐朝李翱的《復性書》。」倘若此說為是，那麼，李翱的「復性」說即為「從『性善』到『性本善』」轉化過程中的一大關鍵處。本文意旨如下：一、重新評估李翱「復性」乙說的理論結構暨其蘊義；二、因李翱深受佛學影響，其所復之「性」與佛教中國化之「佛性」顯然有所關聯，因此，「性本善」或與「佛性」論述相關；三、理解其「性善」、「情邪」的理論模式與朱熹「性本善」之理論（「天地之性」為善，「氣質之性」有善有惡）是否有所關聯。如是，「從『性善』到『性本善』」此一議題當能獲致佐證，同時得以重估中國哲學中人性議題論的發展歷程。

My previous textual study ”from 'Human Nature is Good' to 'Human Nature is Originally Good'” asserted that Mencius' ”Human Nature is Good” (Xing Shan 性善) theory has a different meaning from Chu Xi's 朱熹(Chu Hsi) ”Human Nature is Originally Good” (Xing Ben Shan 性本善) theory. However, this uncommon conclusion needs more evidences than merely textual comparisons between the book of Mencius and Chu Xi's commentaries; otherwise each side of the dispute will stick to his own view. Now this research purposes a developmental study, to find somedefinite process from ”Human Nature is Good” to ”Human Nature is Originally Good”. As Zhu Bo Qun 朱伯崑 said, ”Human Nature is Originally Good” (Xin Ben Shan) theory first occurred in Li Ao's 李翺 Fu Xing Book ＜復性書＞, thus being a crucial literature. This research has three aims. 1. to revalue Li Ao's ”Fu Xing” (returning originally human nature) theory; 2. to understand the connection between theoretical patterns of Li Ao and Chu Xi; 3. because of the enormous influence of Chinese Buddhism upon Li Ao, the ”Xing” (Human Nature) in his theory (thus Chu Xi's Xing Ben Shan theory) probably has deep relation to Buddhism. This research, if appropriate, can rein force my previous conclusion, and give a new consideration in study of human nature in Chinese philosophy.