Humanity

The most influential thinker of Neo-Confucianism was Zhu Xi (1130–1200), who wrote new commentaries on most of the Confucian classics and whose school became the orthodox tradition in China and Korea. Zhu emphasized the "learning of principle" (lixue). The term "principle" (li) appears in the classics, where it refers to a standard or pattern. Zhu contended that there is a principle that underlies all existence and that this can be discerned through studying phenomena. There is one principle, but it is manifested variously in the things of the universe. The myriad phenomena are in a state of constant flux, but all changes are determined by the universal principle. The force behind change is vital energy, which is the means by which principle is manifested. Both principle and vital energy influence each other, and they are central to the proper functioning of both the natural world and human society. Sages regulate and control their vital energy and act in accordance with principle, and thus they are able to manifest human-heartedness, filiality, and righteousness.

In common with the mainstream of the Confucian tradition, Zhu believed that education is the key to both moral behavior and sagehood. His approach is referred to as "investigation of things" (kewu), which involves beginning with what is known and then proceeding to understand the mysterious. Because everything manifests principle, as one investigates things, one progressively comes to understand the nature and elaborations of principle, and this in turn leads to improved wisdom and morality.

Zhu's main opponent was Wang Yangming (1472–1528), who rejected the notion of the exhaustive study of things as a waste of time. He agreed with Zhu that principle is manifested in all phenomena, but held that the human faculty of the heart/mind allows people to discern it directly without an exhaustive study of things. Because humans are innately endowed with the capacity for sagehood, all that is necessary is to engage in introspection using the heart/mind, and through this they can comprehend principle directly.