チベット中観思想における二諦説の設定の起源について――初期チベット人学者の中観典籍を資料として――

抄録

Although various subjects were discussed in Madhyamaka texts both of India and Tibet, the two-truths （Skt. satyadvaya/ Tib. bden gnyis） theory is one of the most important subjects. In discussing the two-truths theory, dGe lugs pa and Sa skya pa scholars of later periods shared the same Sa-bcad format which consists of the following six topics: （1） base of division （dbye gzhi）; （2） meaning of division （dbye ba’i don）; （3） literal meaning （ming gi don）; （4） number-determination （grangs nges pa）; （5） definition （mtshan nyid）; and （6） valid cognition （*pramāṇa） which ascertains a definition （mtshan nyid nges byed kyi tshad ma）. What is to be investigated is by whom and when this Sa-bcad format of six topics was created. I have tried to search for its origin in Madhyamaka texts of the early Tibetan scholars of gSang phu ne’u thog and Pa tshab lo tsā ba Nyi ma grags （ca. 1070-1140） and his followers, and drawn the following three conclusions:

1. It is the early Tibetan scholars of gSang phu ne’u thog around 11-12th centuries who created this Sa-bcad format of six topics, which was commonly accepted by dGe lugs pa and Sa skya pa scholars of later periods.

2. On the other hand, Pa tshab lo tsā ba and his followers did not adopt this format, and more likely, even did not regard the two-truths theory itself as an essential topic of their Madhyamaka thought. They instead regarded Dependent-arising （Skt. pratītyasamutpāda/ Tib. rten ’brel） as a core theory of their Madhyamaka thought.

3. Therefore, two different interpretations of Madhyamaka thought were established by early Tibetan scholars around 11-12th centuries: （1） the interpretation that placed the two-truth theory at the core of Madhyamaka thought, largely accepted by the early gShang phu scholars; and （2） the interpretation that placed the dependent-arising theory at its core, separately propagated by Pa tshab lo tsā ba and his followers.