The purpose of Chih-i’s judging the coarseness and subtlety of the Three Tracks in the Four Teachings is, on one hand, to stress the superiority of the Perfect Teaching by affirming the subtlety of the Threefold Track in the Perfect Teaching, and on the other hand, to foreshadow his argumentation in terms of “opening the coarseness and revealing the subtlety” (K’ai-ts’u Hsien-miao). In Chih-i ‘s view, distinguishing either coarse or subtle teachings is not the real intention of the Buddha. Whereas all entities of the universe are a manifestation of the True Reality, so called coarse dharmas (as relative teaching) actually contain the subtle dharmas (as ultimate teaching). The ultimate teaching reflects the real intention of the Buddha expounding various dharmas whether coarse or subtle, which aim at leading beings to pursue the One Vehicle of Buddhahood. Hence, before the revelation of the real intention of the Buddha, the three teachings (Tripiṭaka, Common, and Separate) were relative and coarse dharma. Only when the coarse dharma is displayed as containing the ultimate teaching of the Buddha, does it become subtle dharma, since it can also guide beings to attain Buddhahood. For this reason, Chih-i argues that the distinction of coarse or subtle only lies in one’s capabilities to conceive of it as such. The subtlety of the Threefold Track as the One Buddha-vehicle is explicated with reference to the Buddha-nature that all sentient beings possess. In view of all beings possessing the Buddha-nature, every being is capable of conceiving the subtle Threefold Track as the One Buddha-vehicle. The reason the vehicle of the Perfect Teaching is subtle is because the practitioner of the Perfect Teaching realizes that that there are no other vehicles to seek except for this One Buddha-vehicle, which can reveal the ultimate Buddha-nature. (Vol. 2, Page 250-251)