Humanistic Buddhism, as one of the most important models of modern Chinese Buddhism, is not without its foundation. Indeed, it is deeply rooted in the history of Chinese Buddhism. The Tiantai school founded in the Sui dynasty, for example, has provided Humanistic Buddhism with rich ideological resources. To begin with, Guoqing Temple, the ancestral temple of the Tiantai School, whose name infers that “once a temple is built, the country will be stable ( 寺若成，國即清).” Furthermore, it expresses that one of the functions of Buddhism is to care for the world, i.e. Buddhism is conducive to national governance and social development. Concerning those who consider the involvement of Humanistic Buddhism in social affairs as proof of its lack of sacredness, the Tiantai thought of the “mutual containment of the ten realms ( 十界互具)” that provides a solid theoretical foundation for the sacredness of Humanistic Buddhism. The so-called mutual containment of the ten realms refers to the Ten Dharma Realms of hell, hungry ghosts, animals, asuras, humans, heavenly beings, śrāvakas, pratyekabuddhas, bodhisattvas, and buddhas. Each contains the nature of the other nine realms. It is often said that, “Everyone has buddha-nature, and every buddha has human-nature,” and this is a good example to illustrate it.
