With the internal development of T’ien-t’ai, the most notably Shanjia-Shanwai debate arose in Northern Song Dynasty. As a big argument in history of T’ien-t’ai, Shanjia-Shanwai debate is important for our research. It can help us to understand abstruse theory of T’ien-t’ai and to see its profound influence.This essay mainly expounds Shanjia-Shanwai debate in three parts. First, the background. Second, the content. Third, the influence.Shanjia-Shanwai debate had its own special background. At the beginning, some scriptures which had lost many years were carried back overseas. And they had different ideas to some sutra. In addition, Shanjia was in Hangzhou while Shanwai was in Ningbo. So they had different school discipline because of their different conditions. Last but not the least, the little discrepancy between Chih-i and Chan-jan resulted in the controversy.In fact, Shanjia and Shanwai opposed in many aspects. But the most essential deputes were three. They were mind-observation theory,particular noumena obeys to conditions and one billion worlds in form. In mind-observation theory, Chih-lih thought that mind had two sides——Noumenon-contained and phenomenon-con- tained, so was sarva-vastu^ni. In Chih-lih’s opinion, mind made sarva-vastu^ni. Chih-lih used explanation in Mo Ho Chih Kuan to tell us that one-thougt was phenomenon-contained. So he emphasized to meditate“Yinshi”. Furthermore, he advocated that we should observe mind step by step. On the contrary, Shanwai believed in oberserving true-mind. In the debate of one billion worlds in form, Shanjia agreed with the notion that‘dharma-realm’contained each other.
