The Kinkō-shū is widely believed to be the work of Nikkō 日向 (1253-1314), one of Nichirenʼs six great disciples. A close look at the text, however, reveals a few details pointing at the necessity of revisiting the problem of its authorship and compilation date. We find, for instance, the Zen kenbun Chapter of the Kinkō-shū describes conflictual relations between the Rinzai and Sōtō schools. We know, however, that relations between the two main branches of Zen Buddhism in Japan were initially amicable and did not become marred by sectarianism until early 14th century. It is thus obvious that the Zen kenbun could not be ascribed to Nikkō himself. The chapter, at least in its extant version, must have been written or redacted later than the first decades of the 14th century by one Nikkōʼs disciples. Another peculiar aspect of the Zen kenbun is its double classification of Zen into three as well as ten traditions, two different taxonomic patterns somehow related to each other but having different origins. The categorization into three types belongs to Nichiren, while the ten-type classification goes back to Dahui’s Analects 大慧語録. It is quite intriguing why the author of the chapter found it important to include a classification peculiar to a Chinese Chan source instead of restricting himself to the categorization adopted by the Patriarch of his own school. Further research is needed to determine whether the author made direct use of the Chinese source(s) for his second taxonomic pattern or borrowed it from a Zen text compiled in Japan.
