Chu Fei-san Fei-i Hsien-i (Abiding in neither the three nor the one and revealing the one) is the function related to the Subtlety of Supramundane Powers. This is spoken of in terms of the principle or phenomenal appearances. In terms of the principle, this is referred by Chih-i to the dharma that is constant without self-nature, since it is empty. From the point of view of emptiness of all dharmas that lack self-nature, the Three Vehicles and the One Vehicle can be perceived as neither the three nor the one. Abiding in neither the three nor the one, the Buddha reveals the seed of Buddhahood that arises from causes and conditions, and this is the revelation of the one. Speaking in terms of the phenomenal appearances, the Buddha constantly uses the human and heavenly vehicle (neither the three nor the one) to lead beings to enter the Greater Vehicle (revealing the one). (Vol. 2, Page 445-446)