Ruan De-Ru and Ji Kang's four articles around "Health Theory of Houses Having no Good Luck or Bad Luck" are the longest and the most controversial ones among Ji's argumentative discourses. Diverse definitions of the debate's two sides blur Ji's role in the history of Wei and Jin Dynasties Daoist metaphysics. This paper first scrutinizes Ruan and Ji's poems with their mutual concern "health preservation" as the focus. The core of the argument is not social customs but different understandings of the health preservation issue. Ruan emphasizes self-cultivation and opposes houses' luck, and Ji further integrates them with the idea that the environment can assist self-cultivation. Ruan's and Ji's thoughts are in different levels, but both of them are products of health preservation philosophy and Ji's development from "self-sufficient inside to "qi throughout inside and outside." Only by observing the two sides and revealing their advantages can readers witness Ji's genius of leading different aspects into one direction in his "Health Preservation Theory." Therefore, Mou Zong-San's hypothesis that Ruan's thought is Ji's thought is probably partially correct, but it should be established on Ji's thought of converting from the static sense to the dynamic subject in the form of qi. Owing to Tang Yong- Tong's widely accepted view, Ji Kang's natural qi view is often considered a residue of the cosmic view in the Han Dynasty. With the perspective this study presents, Ji Kang's thought is no longer framed as the second stage of Wei and Jin Dynasties discourses about existence and nonexistence and ritual teachings, but becomes a new role expanded more completely in the history of Wei and Jin Dynasties Daoist metaphysics.