本文從學者關於唯識學三性說的爭論出發，指出之所以產生這些爭論背後的主要原因是由於唯識學文獻本身即主張不同的三性說模型。本文首先界定兩種三性說模型：單層結構與雙層結構，並且分別簡述其主要特徵。單層結構的主要特徵是：依他起性與遍計所執性之間的關係是能取與所取的關係；雙層結構的主要特徵是：依他起性本身包含有相分、見分的二分，遍計所執性乃是將依他起性作為「所遍計」、在二分之上進一步的概念化與實體化。根據兩個模型的差異，本文接著以《辯中邊論》頌文為核心，分析〈辯中邊論・相品〉頌文中的三性說是單層結構；而〈辯中邊論・真實品〉頌文則與《攝大乘論》一樣，主張雙層結構。根據這個結論，筆者總結過去學者對於《辯中邊論》三性說的誤讀，以及伴隨這些誤讀而來對於現存《辯中邊論》頌文結構的錯誤主張。最後，筆者根據《辯中邊論》中存在兩種不同版本三性說以及《攝大乘論》對於《辯中邊論》引用不一致的兩個線索，提出對於《辯中邊論》頌文結構的新建議：現存《辯中邊論》頌文是一個多層次的文獻，其中有較為古老的層次與較為年輕的層次。

This paper begins with a review of the debates among scholars about how to properly undertand the Theory of Three Natures (trisvabhāva-nirdeśa). I argue that a main reason leading to those debates is because in Yogâcāra texts themselves there are more than one versions of the Theory of Three Natures. I show that at least two models exist: the single-layer model and the double-layer model. The characteristic feature of the single-layer model is that the relation between the dependent nature and the imagined nature is that between the grasper (grāhaka) and the grasped (grāhya). In contrast, the characteristic feature of the double-layer model is that there are two parts—the seeing part and the seen part—in the dependent nature, and the imagined nature takes these two parts as “that which is imagined” (parikalpya) and further conceptualizes and substantializes them. Following this contrast, I then show how the Theory of Three Natures in the fi rst chapter (“Chapter on Marks”) of the Madhyântavibhāga (verses only) coheres with the single-layer model; where the third chapter (“Chapter on The Reality”) endorses the double-layer model. Based on this conclusion, I then summarize the misreadings by previous scholars of the Theory of Three Natures in the Madhyântavibhāga (verses only) and their problematic proposals about the structure of our current text of the Madhyântavibhāga (verses only). Finally, based on the two clues—that there are more than one versions of the Theory of Three Natures in the Madhyântavibhāga (verses only) and that Asaṅga appears to be inconsistent in citing from the Madhyântavibhāga (verses only) in his Mahāyānasaṃgraha—I make a new proposal: our current text of the Madhyântavibhāga (verses only) is a multi-layered text, consisting of older and newer strata.