Chih-i’s further analysis of the relationship between the door of the Traces and the door of the Origin is also his endeavor to demonstrate the polar concept of the substance and the function. In Chih-i’s interpretation of the Lotus Sūtra that is divided by him into two major part, the Traces and the Origin, the Traces highlights the recent event of the Buddha’s self-practice and transformation of others, and the Origin the original enlightenment of the Buddha: the former denotes the function and the latter the substance. In a sense that function is derived from substance, Chih-i confirms that it is due to the original enlightenment of the Buddha in the Origin from which the Buddha’s activities in the Traces are derived. While emphasizing the key role of the Origin as the substance contrary to the Traces as the function, Chih-i does not hesitate to clarify the fact that the function is already contained in the substance as the enlightenment of the Buddha simultaneously arouses the function of saving sentient beings. (Page 63)