Kūkai was the founder of the Shingon sect in Japan. In addition to the theory of “enlightenment in this very body” (Jp. sokushinjōbutsu), Kūkai’s most important concept was his “Theory of the Ten Abiding Minds”, explained in the Jūjūshinron [Ten Abiding Minds Treatise] and the Hizōhōyaku [The Secret Treasure Key]. In later years, Kūkai condensed the ten volumes of the Ten Abiding Minds into three volumes of the Hizōhōyaku. However, in addition to the difference in the length of the volumes, the later-established Hizōhōyaku also emphasises its connection with the Mahāvairocana Sūtra. By quoting from the Mahāvairocana Sūtra in the questions and answers, the Hizōhōyaku expresses the appropriateness and necessity of being a “treatise” (śāstra). In this paper, we will explain the meaning of the Ten Abiding Minds Theory in the Hizōhōyaku, analyse how Kūkai interpreted the sutra, how he interpreted the Avataṃsaka Sūtra, his strategy for arguing against the Tendai school, and his method of interpretation. Taken together, this means that Kūkai’s theory of the Ten Abiding Minds was not based on the Mahāvairocana Sūtra, but rather was his creative idea. These discrepancies reveal Kūkai’s theory of tantric knowledge and his motivation for writing it. This article then explores how this treatise fulfils the role of a śāstra, one of the genres of Buddhist texts, in the cultural context of East Asia.
Keywords:
Kūkai, Shingon School, Mahāvairocana Sūtra, Hizōhōyaku, Jūjūshinron