Lê Quý Dôn (1726-1784), the famous Vietnamese Confucian thinker and philosopher of the 18th century, is strongly influenced by Chinese thought, in particular the Neo-Confucianism of the Song-Ming period. In my last three papers on Lê Quý Dôn, I have pointed out that Zhu Xi (1130-1200), the renowned philosopher of the Song dynasty, has inspired Lê's views of gewu (epistemological investigation of things), liqi (the metaphysical relationship between principle and matter) and religion (including sacrifices to ghosts, gods and ancestors). In this paper, I will discuss how Lê amended Zhu Xi's metaphysics of liqi by giving qi a guiding and dominant role. The Arché Qi is for Lê the common element of all beings and the reason that descendants and ancestors could affect each other in the ceremony of sacrifice. This kind of affective communion is also the foundation of retribution, via which good will be rewarded and evil punished.