Chih-i relates function with power. Compared with the function of other sūtras, the Lotus Sūtra is regarded by Chih-i to possess the powerful function, which can fulfill the task of leading beings to attain Buddhahood. The function is only considered to be powerful if the sūtra conveys the state of Buddhahood. To be specific, Chih-i argues that all other sūtras do not present the Buddha’s knowledge and wisdom, they do not convey that the Buddha responds to his own Traces, they do not directly demolish and abandon the Two Vehicles (Śrāvaka and pratyekabuddha), and do not clear away disciples’ doubts about the recent material body of the bodhisattva as Śākyamuni Buddha. The Lotus Sūtra, on the contrary, does not concern the knowledge of the Two Vehicles and the knowledge of the bodhisattva, but only reveals the subtle knowledge of the Buddha. It does not reveal the knowledge and the perception of living beings in the nine Dharma-realms, but only the subtle knowledge and insight of the Buddha. Chih-i goes on to say that the Lotus Sūtra directly demolishes and abandons the effect of the Two Vehicles by employing a parable of the conjured city (Hua-ch’eng). Like the conjured city that should be abandoned, the practice of the Two Vehicles as the cause should be abandoned too. In the Lotus Sūtra, all types of the expedient teaching are considered to be the Relative Truth in the Traces, and the place of the Origin is revealed as containing real merits and virtues, and represents the Ultimate Truth. (Vol. 2, Page 443-444)