Zhu Xi was one of the most prolific writers in the history of Chinese philosophy. He developed the notion of the li and qi, roughly translated as principle and matter. While there is an inherent and eternal li as part of the nature of everything in the universe, the qi is what condenses the principle and allows for the particular and temporal things that exist in the world. But as the eternal li were as numerous as the things they endowed, there needed to be a ultimate standard in which to unite them, which for Zhu Xi was the Supreme Ultimate or the Tai Ji. This notion of the Tai Ji is something Zhu Xi developed from his predecessor Zhou Dun-yi. Feng You-lan gives an account of Zhu Xi’s description of the Tai Ji in his Short History of Chinese Philosophy (page 297):

“The Supreme Ultimate is simply what is the highest of all, beyond which nothing can be. It is the most high, most mystical and most abstruse, surpassing everything. Lest anyone should imagine that the Supreme Ultimate has bodily form, Lien-hsi (i.e. Zhou Dun-yi) has said of it: ‘The Ultimateless, and yet also the Supreme Ultimate.’ That is, it is in the realm of no things that there is to be found the highest li.”

Fung’s translation of Zhu Xi’s account is interesting as it shows perhaps the greatest Neo-Confucian was influenced by Zhou, who himself was clearly influenced by the content of the Dao De Jing. That being said, it is no secret that the Neo-Confucians took great pains to distance themselves from their Buddhist and Daoist influences. Once again, the highest ideal of a sage in Confucianism was one who took part in the aspects of human life, trying to forge a system where the ultimate goal of ‘peace under heaven’ could prevail. In this passage though, it is hard not to think about the metaphysical beginnings put forth in the Dao De Jing and how they have come to play a part in the development of all Chinese thought. While it may be a stretch to say that Zhu Xi’s cosmology of li, qi and the Supreme Ultimate were influenced directly by the Dao De Jing, I would like to take a look at the relationship between the Dao and De in the next section to outline an interaction between the metaphysical and the world of things much earlier in Chinese thought.