This paper studies meditation as taught in the Kongōkai gōzanze gojūketsugo, a forgery under the name of Kūkai (空海). Two kinds of meditation methods—Susokukan (数息観) and Jirinkan (字輪観)—are taught at the beginning of the text.
The explanation of the Susokukan concentrates on practice with no doctrinal discussion. On the other hand, in its discussion of the Jirinkan, we see not only meditation techniques but also a doctrinal interpretation based on the Tenjiki-tokuchi (転識得智).
The Tenjiki-tokuchi refers to transformation of consciousness into wisdom. This doctrine can be found in other forgeries under the name of Kūkai, such as the Ihon sokushin jōbutsu gi and the Hizō ki. Some common points can be seen in these forgeries. In a nutshell, it seems that the doctrine of Tenjiki-tokuchi had been established and accepted widely at the time of these forgeries, in which Shingon doctrine had been not much developing.
