Abstract
In this paper, I studied the concept of sandi (_??__??_) in the commentaries of Zhiyuan (_??__??_) of the Shanwai (_??__??_) sect and Chuandeng (_??__??_), and Zhixu (_??__??_) of the Ming dynasty. I discovered that they regarded sandi as zhendi (_??__??_), sudi (_??__??_), and zhongdi (_??__??_) (roughly: ultimate truth, conventional truth, and medial truth). And I discovered that Zhiyi (_??__??_) regarded sandi as zhendi, sudi, and zhongdi too, and he didn't regard sandi as kongdi (_??__??_), jiadi (_??__??_), or zhongdi. So I thought that these commentaries faithfully succeeded to Zhiyi's sandi concept.
