Through this study, we come to realize the unique contribution of Chih-i in terms of sign interpretation. That is, truth can be penetrated by means of correctly understanding the arbitrary language of nature. Truth can be exposed through interpreting various signs. For Chih-i, the interpretation of sign becomes a means to demonstrate his own philosophy, whereby his thought is proved to be akin to the principle of the Ultimate Truth. This indicates that Chih-i’s interpretation of the Lotus Sūtra is not just the discourse for speculative philosophy, but is intended to embody Chih-i’s own philosophy in practice, through which his own system of understanding Buddhism as a whole is presented. What Chih-i concerns about is no longer an idea or a metaphysical problem that remains in the domain of discourse, but the methodological and hermeneutical approaches that can demonstrate his philosophy in practice. Ultimately, the goal of his sign interpretation is educational and soteriological. That is, Chih-i strives to convey visually what the Ultimate Truth is, how we can better conceive and understand the profound truth, and how we can approach the attainment of truth through the revelation of his perfect harmonization philosophy. (Page 134)