Structure of the inference in Buddhist logic -on the dufinition of the inference for others-

通过对《法界》第三章“为他人推论的定义”一节的日译，可以发现法界在推论中所使用的“prasanga”具有积极的作用，成为形成"prasangaviparyaya“的一个确立因素。由于他对prasanga论证的简单描述，他的追随者，达摩陀罗和般若波罗蜜多，主张不同的解释。不同的主要点是，提出者是否可以从prasanga中制定出一个自主的prasangaviparyaya，或者关于提出者不可能存在的主体。通过对他们的评论的研究，可以看出，《般若波罗蜜多》对达摩的观点提出了批评，主张对不存在的主体不能形成任何形式的“空相”。根据法身的理论gTsan nag pa（12 c.），最早的藏文释经家之一，阐述了他自己的prasanga理论。我已经表明，丹那霸关于“实相”的理论与般若波罗蜜多的观点有着密切的相似之处。布顿（1290-1364）也提到了法轮和般若波罗蜜多对prasanga论证的不同解释。从他们的评论的文献学研究，可以得出结论，布斯通的典故，在现实中可以追溯到他们的理论。这些研究有助于从印度佛教逻辑的角度阐释藏传佛教逻辑的发展。

Through the Japanese translation of the section "difinition of the inference for others" in the third chapter of Dharmakirti's Pramanaviniscaya (=PVin III) it is found that his prasanga which is used in the inference has a positive function to be an establishing factor for the formulation of contrapositive form (prasangaviparyaya). Because of his simple description of the prasanga-argument, his followers, Dharmottara and Prajnakaragupta, advocate different interpretations. The main point of differnece is whether the proponent can formulate an autonomous prasangaviparyaya from prasanga or not with respect to the subject which can not be existent for the proponent. According to the study of their commentaries, it is made clear that Prajnakaragupta, advocating that no prasangaviparyaya can be formulated with respect to the nonexistent subject, criticizes Dharmottara's view.Dharmakirti's prasanga-theory exerts a great influence on the Tibetan Buddhist logic. On the basis of Dharmakirit's theory gTsan nag pa (12th c.), one of the earliest Tibetan commentators of the PVin, expounds his own prasanga-theory. I have showed that gTan nag pa's theory on the subject of prasanga-viparyaya bears a close parallel to Prajnakaragupta's view. Bu ston (1290-1364) also alludes to the difference of interpretation on the prasanga-argument between Dharmottara and Prajnakaragupta. From the philological study of their commentaries it follows that Bu ston's allusion can in reality be traced back to their theories. These studies contribute to the elucidation of the development of the Tibetan Buddhist logic from the Indian Buddhist logic from the viewpoint of the interpretation of prasanga.