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 Sincerity. Sincerity (chéng) is a subtle and multifaceted notion in Neo–Confucian thought.  However, the Great Learning focuses on one key aspect of it: “What is meant by ‘making thoughts have Sincerity’ is to let there be no self–deception. It is like hating a hateful odor, or loving a lovely sight.  The is called not being conflicted” (Tiwald and Van Norden 2014, 191). In other words, humans engage in wrongdoing through a sort of self–deception in which they allow themselves to ignore the promptings of their moral sense, and become motivated solely by their physical desires for sex, food, wealth, etc.  Once one knows what is right and wrong, one must then make an effort to keep that knowledge present to one’s consciousness, so that it becomes motivationally efficacious.  As Zhu Xi explains, “…those who desire to cultivate themselves, when they know to do good in order to avoid the bad, must then genuinely make an effort and forbid self–deception, making their hatred of the [ethically] hateful be like their hating a hateful odor, and their loving what is good like their loving a lovely sight” (Tiwald and Van Norden 2014, 192).  