In Zhang Ju on the Doctrine of the Mean, Zhu Xi gives his interpretations to “Knowing, Mercy and Courage” and suggests that “Knowing, Mercy and Courage” means “choosing the good” and then “being persevere”, among which there exits both distinction and relevance. More importantly, by combining his understanding of “Knowing, Mercy and Courage” with “the Mean”, Zhu Xi emphasizes on “Sincerity”. This can offer us profound thinking space to construct a new core value.