While Shōken, alongside Raiyu, is an important learned monk in the context of the doctrinal history of Shingi Shingon, very little research has been carried out concerning Shōken in comparison to Raiyu. Moreover, in the context of the study of the Shingon sectarian doctrine, Shōken remains situated as Raiyu’s doctrinal successor. Certainly, Shōken’s academic tradition carries on Raiyu’s teaching, but some areas are evident in which his interpretations differ from those of Raiyu, and some doctrine exists that is unique to Shōken. This paper takes up Shōken’s compilation of the Jishō seppō jūhachi-dan [Eighteen Sermons on Achieving Enlightenment Unaided], and in addition to considering the characteristic features of Shōken’s scholasticism, it also touches on the significance of Shōken in the history of the Shingi Shingon doctrine. Although Shōken’s scholasticism was fundamentally based on that of Raiyu, in several occasions, he advances his own views as well. Even so, the most distinctive characteristic is how he has managed to organize and summarize Raiyu’s complicated discussions in an easily comprehensible fashion. In such circumstances, Shōken organized, systematized, and added new interpretations to Raiyu’s teachings, which had been immature as doctrine, to bring them to completion. Retracing the history of Shingi Shingon doctrine in this regard has thus confirmed the significance of Shōken therein.
