Abstract: By interpreting the chapter "Knowing Speech and Nourishing the Spirit" of Mencius, WANG Chuanshan thinks that Gaozi holds the view of "keeping mind still with Tao", but Mencius holds the view of "Tao, so keeping mind still". Under the premise of the ontology of Qi(气), WANG Chuanshan combines "clinging to ambition", "accumulation of righteousness", "nourishing the spirit" and "knowing speech" into an organic whole, revealing the Qi(气)characteristic of the mentality theory of Mencius.