Six theories attributed to the so-called Sarvāstivādins of the Western Region 西方諸師 are found in the Nyāyānusāriṇī （NA, 順正理論, T. 1562）. This article examines one of them, in which the supernormal knowledge of the past lifetimes of oneself and others （pūrvanivāsānusmṛtyabhijñā） is debated. The seventh chapter of the NA, analyzing the six supernormal knowledges, examines the relation between supernormal knowledge of the past lifetimes of oneself and others and the ten wisdoms. It is the orthodox understanding of the Sarvāstivādins that supernormal knowledge of the past lifetimes of oneself and others is limited to mundane wisdom 世俗知. On the other hand, the Sarvāstivādins of the Western Region define this knowledge as the six wisdoms as a whole. This definition was firstly argued by Ghoṣaka in the *Abhidharma Mahāvibhāṣā. In addition, the Apitanxinlun 阿毘曇心論 and the Apitanxinlunjing 阿毘曇心論経 accept this definition as orthodox. Furthermore, its theoretical background suggests that Ghoṣaka had an understanding of the ten wisdoms different from the orthodox theory of the Sarvāstivādins. In order to confirm this hypothesis, however, a detailed study of the theory of eight wisdoms in the *Abhidharma Mahāvibhāṣa is needed.
