Zhu Xi (Chu Hsi, 1130-1200) was a Chinese Neo-Confucian philosopher who emphasized the concept of principle (li) as a theory of the nature of reality. He explored and elaborated the teachings of Cheng Yi that principle is an undifferentiated unity, and he was thus a founder of the Cheng-Zhu School or School of Principle. He wrote commentaries on The Analects of Confucius, The Book of Mencius, The Great Learning, and The Doctrine of the Mean, bringing these works together as a collection called The Four Books. His commentaries on The Four Books and his interpretations of the writings of other philosophers such as Zhou Dunyi (Chou Tun-i, 1017-73), Zhang Zai (Chang Tsai, 1020—77), Cheng Hao (1032-85) and Cheng Yi (1013-1107) had a lasting impact on the course of Chinese Neo-Confucian philosophy.
According to Zhu Xi, principle (li) is inseparable from material force or cosmic energy (xi). Wherever there is li, there is qi, and wherever there is qi, there is li. Without material force, there would be nothing in which principle could settle or dwell to govern the transformations of the physical world. Without li, there would be nothing to govern the interactions of yin and yang that produce the endless transformations of qi. Li is eternal and unchanging, but qi is continually changing in form, due to an endless process of expansion and contraction. Li is incorporeal and nonmaterial, but qi may take a corporeal form. Li is the nature and destiny of things, but qi is neither the nature nor the destiny of things.1
Principle (li) is ultimate reality, and it is an absolute unity. It is also the reason for the transformations of qi. All the myriad things in the universe are transformations of qi. Heaven and earth are transformations of qi, and both li and qi are spread throughout the universe.2
Qi is a force or energy that may be transformed into rain, thunder, lightning, and stars. It may also take the form of the “five agents” (metal, wood, fire, water, and earth). Its integration may produce life, but its disintegration may produce death.
Yin and yang are opposing but complementary aspects of material force. Yin is passivity, but yang is activity. Yin is cold, but yang is hot. Yin is winter, but yang is summer. Yin is the moon, but yang is the sun. Yin is the earth, but yang is heaven.
In order to live in harmony with the world, says Zhu Xi, we must attain a state of balance between yin and yang. We must attain a state of balance between restfulness and exertion, and between passivity and activity. The balance between yin and yang is attained by following the principle of the mean.
To attain a state of balance between yin and yang is to be in harmony with the principle of heaven. Equilibrium in the mind maintains harmony with the world. Tranquility may be found in activity, but equilibrium is the original condition before the feelings of pleasure, anger, sorrow, and joy have been aroused.4
Li is also referred to by Zhu Xi as the “principle of nature” or the “principle of the mind.” However, it is not a mental process or a mode of consciousness. Consciousness is produced not by li, but by qi (material force). The mind, spirit, and soul are all produced by transformations of qi.
Li as a universal reality is also the Great Ultimate (Tai xi). The Great Ultimate is the principle of heaven and earth, and it is the principle of all the myriad things in the universe. It is also the moral nature of principle, and it is the principle of the highest good.
The Great Ultimate, according to Zhu Xi, is a principle that may be found in every person. Every person therefore has, as an original principle of nature, the principle of the four virtues (benevolence, righteousness, propriety, and wisdom). Human nature is originally good, and each human being has only to seek his original nature to find the Way (Dao), which is the principle of heaven. Evil is the result of selfish desires that keep the principle of nature from freely operating. If selfish desires are overcome, then the principle of nature can operate freely, and humaneness (ren) can be fully expressed as a moral virtue.
Zhu Xi emphasizes the importance of ren (humaneness or benevolence) as a unifying moral virtue. Ren unifies righteousness (yi), propriety (li), wisdom (zhi), and sincerity (xin). If ren is maintained as a principle of mind, then righteousness, propriety, wisdom, and sincerity can be fully expressed. Methods by which ren can be applied as a principle of action can be discovered by intensive study, careful inquiry, steadfast attention to purpose, and reflection on things at hand.
Ren is a principle of love, humaneness, and benevolence. It is the way of heaven, and it is therefore a principle of ethical conduct for all human beings. The original nature of human beings is good, because the Great Ultimate is in every human being. Good actions are actions that are in harmony with the original nature of human beings.
Zhu Xi agrees with Cheng Yi that principle (li) is an undifferentiated unity that may have many manifestations. Each being or thing in the universe has its own principle, but the varying modes of principle in all beings and things are manifestations of the absolute unity of the Great Ultimate. An implication of this theory is that although the Great Ultimate is the principle of being, it itself cannot properly be defined as being. Being and non-being are transformations of material force (xi).
In Zhu Xi’s cosmology, heaven, earth, and all the myriad things in the universe develop through four stages: (1) origination, (2) flourishing, (3) advantage, and (4) firmness. These “four qualities” are comparable to the changing of the seasons: origination corresponds to spring, flourishing to summer, advantage to fall, and firmness to winter. Origination unifies the four qualities, just as ren unifies the four virtues.
Mengzi (c. 371- c. 289 B.C.E.) teaches that there are four beginnings: (1) the sense of commiseration is the beginning of humaneness, (2) the sense of shame is the beginning of righteousness, (3) the sense of deference and compliance is the beginning of propriety, and (4) the sense of right and wrong is the beginning of wisdom.5 Zhu Xi agrees with this teaching of Mengzi, but he adds that ren permeates the four beginnings, just as it embraces the four virtues (ren, yi, li, and zhi).
Zhu Xi’s philosophy is rationalistic in affirming that we can discover the reason for everything in the universe if we fully investigate the principle of nature. To know the principle of nature is to understand the nature of things, and it is to discover their destiny. There is nothing in which there is not a principle of nature.
Zhu Xi’s teaching that principle (li) is the inherent nature of all things differs from the Buddhist teaching that all things are empty of any inherently existing reality. According to the Buddhist concept of emptiness, all phenomena are empty of inherent existence, because all phenomena are dependent on causes and conditions of existence. However, Zhu Xi rejects this concept, describing it as a theory that the phenomenal world is illusory. His criticism of the concept of emptiness may be based on a misunderstanding of the teachings of Buddhism, however.6
In rejecting the theory that all phenomena are empty of inherent existence, Zhu Xi teaches that principle is the inherent nature of all phenomena. Principle is real, and not illusory, he says. Principle is the nature of the physical world, and it is the reality that gives being to all things.
1Chu Hsi, Selections from “The Complete Works of Chu Hsi,” translated by Wing-tsit Chan, in A Source Book in Chinese Philosophy (Princeton: Princeton University Press, 1963), p. 613.
2Ibid., p. 636.
3Ibid., p. 637.
5Ibid., pp. 595-598.
6Wing-tsit Chan, A Source Book in Chinese Philosophy (Princeton: Princeton University Press, 1963) p. 653.