Zhiyi

Zhiyi (538–597 CE), also known as Tiantai Zhiyi, was a Chinese Buddhist monk who is traditionally regarded as the founder of the Tiantai school. Associated with Tiantai Mountain in what is now Zhejiang, he systematized and synthesized earlier Buddhist teachings into a coherent doctrinal framework that became highly influential in East Asia.

Zhiyi is best known for elevating the Lotus Sutra as the central and culminating teaching of the Buddha’s path. He taught that the sutra presents the full spectrum of Buddhist doctrine and that its truth can be realized through disciplined study and meditative practice. His distinctive contributions include the doctrine of the Threefold Truth (emptiness, conventional existence, and the middle way) and the idea that all phenomena are interrelated within a single moment of mind, encapsulated in the concept often summarized as “three thousand realms in a single thought moment.” He also arranged the Lotus Sutra’s content into a framework of five periods, and he promoted a comprehensive program of cultivation known as the Tiantai method, combining quieting of the mind and attentive investigation.

Zhiyi authored influential treatises, including the Mohe zhiguan (The Great Calming and Insight), which outlines meditation methods and the integration of calm and insight with doctrinal study. His writings and teaching presented a systematic path that integrated doctrinal exegesis, meditation, and ethical conduct.

Impact and legacy: Zhiyi’s Tiantai doctrine became a major school in Chinese Buddhism and significantly shaped East Asian Buddhist thought. In Japan, the Tendai school—founded by Saicho (Dendai)—adopted Tiantai teachings and influenced later movements, including elements of Zen and Pure Land traditions. His work remains a foundational reference for Tiantai and related lineages.