As important as learning was for Zhu Xi, he stressed that it was possible to know what is right and wrong yet not act on it: “Knowledge and action always need each other. It’s like how eyes cannot walk without feet, but feet cannot see without eyes. If we discuss them in terms of their sequence, knowledge comes first. But if we discuss them in terms of importance, action is what is important” (Tiwald and Van Norden 2014, 180–81). What connects knowledge and action, on Zhu Xi’s account, is Sin