Essay on the Protection of the Nation, An ［守護国界章］ ( Shugo-kokkai-shō): A work written in 818 by Dengyō, the founder of the Japanese Tendai school. It refutes the arguments of Tokuitsu, a priest of the Japanese Dharma Characteristics (Hossō) school. Tokuitsu criticized Dengyō and the Tendai teachings from the standpoint of Dharma Characteristics doctrine. Tokuitsu asserted that the one vehicle teaching of the Lotus Sutra is a provisional teaching, while the three vehicle teachings are true teachings, and that some people are without the potential to attain Buddhahood. Countering this assertion, Dengyō maintained in this work that all people have the Buddha nature, and that the supreme vehicle of Buddhahood, or the one vehicle teaching, of the Lotus Sutra is the true teaching that leads all people to Buddhahood. An Essay on the Protection of the Nation is regarded as one of Dengyō’s major writings.