Chih-i concludes that [his three analogies concerning Ultimate Truth as substance] embody the subtleties of substance, function, and gist. The substance of the Lotus Sūtra as the Ultimate Truth is like the big elephant touching the bottom of mud, so firm that this substance cannot be destroyed. This analogizes the Subtlety of Substance (T’i-miao). The wishing-grant gem Ju-i that rains down treasures analogizes the Subtlety of Function (Yung-miao). The skilled wisdom of the bodhisattva of the Perfect Teaching analogizes the Subtlety of Gist (Tsung-miao). Chih-i adds that these three subtleties that cannot be conceptualized as either vertical or horizontal are named “Greater Vehicle.” (Vol. 2, Page 412)