Li (principle)

Li, written 理 and distinct from the li 禮 of ritual, originally meant the pattern or veins in jade, and came to mean order or principle. In the Neo-Confucian philosophy of Cheng Yi and Zhu Xi it is the principle that makes each thing what it is and ought to be: the pattern of a bamboo, the duty of a son, the nature of the human heart.

Zhu Xi taught that all things are made of principle and qi, vital energy or material force. Principle is one, but its manifestations are many: each thing has its own principle, and all principles together are the Supreme Ultimate (taiji), which is wholly present in each thing, as the one moon is reflected whole in many streams. Human nature is principle; evil arises from the turbid qi that obscures it.

The way to the good, for Zhu Xi, is the “investigation of things” (gewu), the patient study of principle in things, texts and conduct, until one day a breakthrough brings comprehensive understanding. Wang Yangming rejected this method, holding that principle is not to be sought outside the mind, since the mind itself is principle.