《佛性論》之佛性觀與如來藏義析探

Abstract

《佛性論》世親 （Vasubandhu，亦譯天親）菩薩造，陳天竺三藏真諦 （ Paramārtha，499－569）譯， 收於《大正藏》第三十一冊。全論共四卷，由〈緣起分〉、〈破執分〉、〈顯體分〉、〈辯相分〉等四分十六品組成，是一部廣泛議論「佛性」的論典。近代學人多認為最能代表如來藏思想者，除了所謂「三經一論」(《如來藏經》、《不增不滅經》、《勝鬘夫人經》、《寶性論》)外，《佛性論》亦是一部不能 忽視的論典。然筆者觀察，此論雖受推崇但不受重視，尤其在漢傳佛教史上，更難與類似論典（如《寶性論》、《起信論》）相提並論。值此機緣，筆者試著從義理詮釋和文獻研究的角度，對此論作廣泛的探討，主要目標則放在此論的佛性觀與如來藏義上。 為此，筆者將循著以下的理路來進行：第一，匯整此論的成書相關研究資料，清楚掌握此論的組成架構與論述主題，並解讀、詮釋其內容要義。第二，探討《佛性論》中所見到的佛性觀，並釐清論中「分別部」所指何義。第三，透過和其他相關典籍的比對，探討此論的思想源流，理出其教理上的特色。以此說明《佛性論》是如何來解釋如來藏義，並突顯其在大乘佛教思想上的特殊屬性。這三個進路的研究過程、結果，分別成為本論文之第二、三、四章之組成架構，亦成為本論文之核心要素。 透過義理和源流這兩個面向的考察，筆者認為此論在組織架構與義理闡述上確有其獨到之處。綜觀此論幾乎涵蓋了當時印度大乘各宗的教義，舉凡中觀、瑜伽、如來藏無不融涉，同時又增加了一些新義，是一部相當富有自己特色的佛性論典。筆者雖認同本論是闡述「一切眾生悉有佛性」的論書，但予其說是對單一論典（《寶性論》的5、6、7三品）的重作闡述，倒不如說是作者假佛性議題，試圖將如來藏與唯識學作一深切溝通。本論文就是從世親的學思背景的雙重角色中，對論中所涉及到的佛性觀和如來藏義作一整理、剖析。

Buddhagotraśāstra attributed to Vasubandhu was translated into Chinese by Paramārtha（499－569） which is called Foxing Lung (Taishō 1610). Foxing Lung comprises four fascicles subdivided into sixteen chapters: section on causes and conditions for the teaching, section on refutation of other views, section on the essence of Buddha nature, and section on characteristics of Buddha nature. It presents an extensive elucidation on Buddha nature. Most of contemporary scholars agree that along with the so-called “three sūtras and one śāstra” (Tathāgatagarbha sūtra, Anūnatvāpūrṇatvanirdeśa parivarta, Śrīmālā sūtra, and Ratnagotravibhāga), Foxing Lung should not be ignored in understanding tathāgatagarbha, but in Chinese Buddhism, the significance of Foxing Lung has not received enough attention as Ratnagotravibhāga or Awakening of Faith in the Mahāyāna (《大乘起信論》). In this paper, I intend to discuss the meaning of Buddha nature and tathāgatagarbha in Foxing Lung from both philosophical and philological aspects. The approach I employ in present paper includes three parts. Firstly, I will go through the academic studies related to the authorship of Buddhagotraśāstra, and clarify the structure and elaborate some doctrinal issues in Foxing Lung. Then I will focus on the concept of Buddha nature revealed in Foxing Lung, and also clarify what “Vibhajyavādin” exactly is in this treatise. Thirdly, through comparing with other related texts, I will investigate the origin of the thought of Foxing Lung, and will inquire the philosophical features. The discussions from these three aspects correspond to chapter two, chapter three and chapter four of this paper respectively which are the core elements. After thoroughly investigating the philosophy and the origin, I will argue the special features of the structure and the doctrinal interpretation of Foxing Lung are distinctive. Foxing Lung covers Mahāyāna teachings of its time, such as mādhyamaka, yogācāra, tathāgatagarbha and so on; moreover, it presents new perspectives. Although I agree that Foxing Lung is one of the treatises elaborating “all sentient beings have the Buddha nature”, I will claim that instead of further explaining three chaptes (5, 6, and 7) of Ratnagotravibhāga, the composer of Foxing Lung tries to reconcile and unite tathāgatagarbha and mind-only doctrines via the theme “Buddha nature”. In this paper, I try to analysize and induce the concept of Buddha nature and tathāgatagarbha in Foxing Lung without ignoring the dual role Vasubandhu endowed with.