Some documents belonging to "the system of tenents"(Tib. grub mtha'; Skt. siddhanta) have been discovered from Tun-huang. One of them, called "Distinction ofviews; Tib. lTa ba'i khyad par" is the oldest document.It describes the school that is a combination of the `Sautrantika-Madhyamika` and `Yogacara-MadhyamiKKa`.
This document is aimed to clarify the situation of Buddhism in Central Tibet (dBus) at the beginning of he ninth century. As Professor Daishun Ueyama has pointed out, the same material has been kept in the Tibetan `Tripitaka`, but the text is mixed and has any missing parts; two-thirds of the Tun-huang Version an be used to correct the corresponding parts in the Tibetan `Tripitaka`.
For the two reasons mentioned above, this document is very important. We believe that, for Sino-Tibetan cultural interchanges or Hindu-Tibetan relationships, the document can provide us much material for further vesearch. Hence I take courage to translate it into chinese. Of course Professor Ueyama's articles are very useful during the translation work. So I am very much obliged to him.