In this essay, I argue that in Mengzi 2A2 Mengzi 孟子 proposes his method for cultivating righteousness by showing that on the way of achieving yi, such topics as the unperturbed hearts, cultivating courage, Gaozi’s 告子 maxim, and the flood-like qi 氣 ultimately converge. Toward this aim, first, I argue that Mengzi’s short remark “bi you shi yan er wu zheng, xin wu wang, wu zhu zhang 必有事焉而勿正, 心勿忘, 勿助長” can be read as his maxim for achieving yi that structurally (...) parallels with the preceding maxim of Gaozi that Mengzi quoted. It tells us that neither our blind obedience to the words nor our impetuous boost of qi is helpful for achieving yi; instead we should concentrate on the heart’s moral sentiments and perform righteous actions. Second, I argue that Mengzi believes that qi is crucial in one’s proper self-cultivation. The centrality of moral sentiment in his teaching redirects our attention to qi’s positive aspects—exemplified by the flood-like qi—though qi’s impulsivity often makes it appear negative. If the four sprouts are to accompany the spontaneous movement of qi, it can be said that properly expressed qi signals the moral health of one’s heart. Moreover, I show that strong positive qi not only constitutes moral sentiment that serves as a fair standard for self-examination but also leads the will to perform moral actions without delay. (shrink)