Mou Zong-San has ever divided the Neo-confucianism into two styles: existing and active, as well as existing but not active. Classified to be the latter, Zhuzi's theory is designed under the motive for the empirical facts of evil. Generally speaking, Monism inevitably encounters the problem of virtue and vice caused by the same substance. To keep the Li (principle) purely good in explanation of source of evil, Zhuzi has the statement that the Li (principle) doesn't act, only attaching to the Qi(material force). With Li as purely good, so Zhuzi disagrees about the nature to be neither good nor evil. According to Zhuzi's theory, phenomena are organized by both Li and Qi. Consequently, the vice is constituted in the form of evil. Furthermore, Zhuzi also defined phenomena as Li permeating qi, which means Li may act through Qi. Therefore, the possibility of both virtue and vice in the substance may be inferred from Li, which represents perfection of Li would be transcendental rather than ethical.