Interpretation of Yi Guan and Zhong Shu in the Song Dynasty were not much debated by the Confucian Scholars. After the rise of the study of moral life in the Northern Song Dynasty, most of the Confucians in the Song Dynasty equated the consistent “Yi (one)” with Tao, regarding “loyalty and forgiveness” as being inconsistent with Tao, which became a popular opinion. Therefore, Zeng Zi was considered to have no understanding of Tao, which was mainly reflected in the new academic interpretation of Wang Anshi and Chen Xiangdao. In order to answer these questions, Su Shi and Su Zhe and many Cheng scholars regarded Zhong Shu as Zeng Zi's academic instruction, but Cheng Hao and Cheng Yi affirmed that Zhong Shu could be interpreted as consistency through complicated theoretical construction. Zhu Xi criticall y adopted both views. He not only used Cheng Hao & Cheng Yi's view as reference to interpre t consistency and loyalty and forgiveness, but also strongly emphasized the practice of loyalty and forgiveness in the doctrine of the Mean, which creatively paved the prelude for Zeng Zi's proposal of careful investigation and painstaking accumulation of knowledge in Da Xue.