The Development of Esoteric Buddhist Scholasticism in Early Medieval Japan

In the late eleventh century, a scholastic monk at the monastic center of Ninnaji compiled the first catalogue of writings by the cultural hero and revered founder of the Shingon school of esoteric Buddhism in Japan, Kōbō Daishi Kūkai. Among these works, the Treatise Distinguishing the Two Teachings of the Exoteric and Esoteric was praised as the premier tractate on esoteric Buddhist doctrine and the foundational document of Shingon school. The Treatise continued to play a central role in the formation of a Shingon sectarian identity, inspiring numerous medieval commentaries as well as studies by modern scholars. However, there is no evidence that this seminal doctrinal treatise ever existed before appearing in catalogues in the late eleventh and twelfth centuries. In this dissertation, I explore the textual history of the Treatise on the Two Teachings and call into question the legitimacy of its origin. Furthermore, by comparing the content of this text with two late ninth-century compendia on esoteric Buddhist doctrine, I propose that the Treatise may have been a polemical response to post-Kūkai developments in the Tendai school. Ultimately, I conclude that esoteric Buddhism in Japan developed as a scholastic discourse regarding the path toward buddhahood. This discourse was not the creation of a semi-legendary founding figure, nor can it be reduced to a single foundational text. Rather, esoteric Buddhism was a scholastic tradition consisting of sundry perspectives and interpretations that developed over the course of centuries. The Treatise on the Two Teachings reflects a decidedly contentious example of this tradition