Zhu Xi or Chu Hsi (Chinese: 朱熹, October 18, 1130 – April 23, 1200) was a Song dynasty Confucian scholar who was the leading figure of the School of Principle and the most influential rationalist Neo-Confucian in China. His contributions to Chinese philosophy including his assigning special significance to the Analects, the Mencius, the Great Learning, and the Doctrine of the Mean (the Four Books), his emphasis on the investigation of things (gewu), and the synthesis of all fundamental Confucian concepts, formed the basis of Chinese bureaucracy and government for over 700 years. He has been called the second most influential thinker in Chinese history, after Confucius himself.
During the Song Dynasty, Zhu Xi’s teachings were considered to be unorthodox. Rather than focusing on the I Ching like other Neo-Confucians, he chose to emphasize the Four Books as the core curriculum for aspiring scholar officials. For all these classics he wrote extensive commentaries that were not widely recognized in his time; however, they later became accepted as the standard commentaries.
Zhu Xi considered the earlier Confucian Xun Zi to be a heretic for departing from Mencius‘ idea of innate human goodness. Even if people displayed immoral behaviour, the supreme regulative principle was good.
Clarity of mind and purity of heart are ideal in Confucian philosophy. In the following poem, “Reflections While Reading – 1” Zhu Xi illustrates this concept by comparing the mind to a mirror, left covered until needed that simply reflects the world around it, staying clear by the flowing waters symbolizing the Tao.
Zhu Xi did not hold to traditional ideas of God or Heaven (Tian), though he discussed how his own ideas mirrored the traditional concepts. Although he practiced some forms of ancestor worship, he disagreed that the souls of ancestors existed, believing instead that ancestor worship is a form of remembrance and gratitude.
Zhu Xi practiced a form of daily meditation called jingzuo similar to, but not the same as, Buddhist dhyana or chan ding (Wade-Giles: ch’an-ting). His meditation did not require the cessation of all thinking as in some forms of Buddhism; rather, it was characterised by quiet introspection that helped to balance various aspects of one’s personality and allowed for focused thought and concentration.
His form of meditation was by nature Confucian in the sense that it was concerned with morality. His meditation attempted to reason and feel in harmony with the universe. He believed that this type of meditation brought humanity closer together and more into harmony.
He found Buddhist principles to be darkening and deluding the original mind as well as destroying human relations.
Edited from Wikipedia