Zhou Dunyi 周敦頤 (1017-1073), original name Dunshi 敦實 (name change in order to avoid the tabooed personal name of Emperor Yingzong 宋英宗), courtesy name Maoshu 茂叔, style Lianxi Xiansheng 濂溪先生, also known as Zhouzi 周子 "Master Zhou", was and one of the five great Neo-Confucian scholars of the Northern Song period 北宋 (960-1126) (Beisong wu zi 北宋五子), the others being Shao Yong 邵雍 (1011-1077), Zhang Zai 張載 (1020-1077), and the brothers Cheng Hao 程顥 (1032-1085) and Cheng Yi 程頤 (1033-1107).
Zhou hailed from Yingdao 營道 in the prefecture of Daozhou 道州 (today's Daoxian 道縣, Hunan). He was recorder (zhubu 主簿), in the Directorate for the Palace Buildings (jiangzuo jian 將作監), then recorder in the district of Fenning 分寧, prefecture of Hongzhou 洪州, administrator for public order (sili canjun 司理參軍), in the military prefecture of Nan'an 南安軍, district magistrate of Guiyang 桂陽, prefecture of Chenzhou 郴州, controller-general (tongpan 通判) of Qianzhou 虔州, provisional prefect (sheshi 攝事) of Shaozhou 邵州, assistant transport commissioner (zhuanyun panguan 轉運判官) of the circuit of Guangnan-Dong 廣南東路, then superintendent of penal affairs (tidian xingyu 提點刑獄) of that circuit, and finished his career as military prefect (zhijun 知軍) of the military prefecture of Nankang 南康.
In 1120, Zhou Dunyi was posthumously awarded the honorific name Zhou Yuangong 周元公. In 1241, he was even formally invested as Earl of Runan 汝南伯, and his spirit tablets were put into Confucius temples. In 1314, his soul was honorifically promoted by granting Zhou posthumously the title of Duke of Dao 道國公.
As a philosopher, he was for a year the teacher of the brothers Cheng, the eventual heroes of Northern-Song philosophy. Zhou was an expert in a novel exegesis of the Classic Yijing 易經, and compiled a brief book explaining the cosmos on the base of Yijing concepts, Taiji tushuo 太極圖說 (original title Taijitu yishuo 太極圖易說), and a more methodological book on this matter, Tongshuo 通書. Zhou belonged to the school of symbols and numbers (xiangshupai 象數派) which was, according to Zhu Zhen 朱震 (d. 1138) and Hu Hong 胡宏 (1105-1161), influenced by the Daoist philosopher Chen Tuan 陳摶 (871-989) and his Xiantiantu 先天圖 "Chart of the Anterior Heaven" or Wujitu 無極圖 "Chart of the Zero-Dimension". The combination of Daoist cosmology and Confucian concepts brought about the emergence of Neo-Confucianism, which laid ancient ideas on the right order of society on a higher, metaphysical level. In the book Tongshu, for instance, Zhou described the cosmic (or "natural") origins of the human character (xing 性), the human mind (xin 心), and social relations (lunli 倫理). Many aspects of Zhou's philosophy were influenced by Buddhism and Daoism.
According to Zhou's theory, the cosmos emerged out of a zero-dimension or non-polarity (wuji 無極) which spontaneously expanded to an extreme dimension or "utmost extreme or polarity" (taiji 太極), in which movements (dong 動) first developed as Yang 陽 "energies" or potentials. These movements reached their zenith and then calmed down to tranquility (jing 靜) as Yin 陰 "energies" or potentials. As to what the zero-dimension and the Utmost Extreme were or meant, Zhou provided no explanation. The two conditions (liang yi 兩儀) Yin and Yang or quietness and movement alternated in circles. If the Yang status had reached is utmost point, it decreased and transformed into the Yin status. Out of these, the five types of matter (wuqi 五氣) formed which can be seen as the five agents water, fire, wood, metal, and earth. They had an interplay with the four seasons (sishi 四時) and brought about the ten thousand beings (wanwu 萬物), including mankind.
Of all objects, man was the most acute one (ling 靈), and among all humans, the perfect man or perfect ruler (shengren 聖人), who was able to discern between good and bad by returning to the status of quiescence. In this mode, the perfect man acted according to the golden mean and ruled with righteousness and propriety (ren yi 仁義). His sincerity (cheng 誠) was the root of the five types of social relationships (wuchang zhi ben 五常之本, i.e. sovereign – minister, father – son, husband – wife, older – younger brother, and friends), and the source of the hundred comportments (baixing zhi yuan 百行之原). The perfect man was enlightened by the refinement of his sincerity (cheng jing gu ming 誠精故明), he was marvelous because his divinity was responsive (shen ying gu miao 神應故妙), and he was mysterious because his explorations were subtle (ji wei gu you 幾微故幽). These tenets were a metaphysical transformation of the concept of sincerity as described in the Classic Zhongyong 中庸.
With the help of Yang, Heaven produced the ten thousand things (yi Yang sheng wanwu 以陽生萬物), and by means of Yin perfected them (yi Yin cheng wanwu 以陰成萬物). "Production" meant, to given them kindness (ren), and "perfection", to implant in them righteousness (yi). The perfect man (or prefect ruler) with his pure mind (chun xin 純心) would grow the ten thousand things by kindness (yi ren yu wanwu 以仁育萬物), and rectify the people by righteousness (yi yi zheng wanmin 以義正萬民). If the Heavenly Way was active, the ten thousand things would comply (shun 順), and if the perfect man exerted his virtuous government, the people would be transformed (hua 化). The perfect man or ruler was in possession of knowledge about the principles (li 理) of rituals (li 禮) by which the relations between sovereign and minister, father and son, and husband and wife were made harmoniously (he 和).
The natural character of sincerity was absolute quiescence, but human life meant movement, and therefore man's character had the active potential (ji 幾) of deviation from the original goodness and possessed good as well as bad aspects. The perfect man alone would focus on quiescence (zhu jing 主靜), abolish his desires (wu yu 無欲) and be cautious in movements (shen dong 慎動) in order to achieve congruence of man with the Utmost Extreme (renji 人極). In practice, this meant central harmony, uprightness, kindness, and righteousness (zhong zheng ren yi 中正仁義), obtained by perseverant learning and self cultivation. Only in this way, man would be able to discard evil aspects in his mind. For this reason, the position of teachers was very high. If teachers were able to establish the Dao 道 (the universal path), people would become good, and the more people became good, the imperial court would be rectified and the world governed in a harmonious way.
How much of Zhou Dunyi's philosophy influenced the Cheng brothers, is still under discussion. Even if the foundation of metaphysical concepts like the Utmost Extreme or the interplay of Yin and Yang was laid down by Zhou Dunyi, the Cheng brothers truly "invented" the concept of the universal or Heavenly principle (tianli 天理) by equalizing it with the Utmost Extreme or the Dao. It was only Zhu Xi 朱熹 (1130-1200) and Zhang Shi 張栻 (1133-1180) who studied the writings of Zhou Dunyi during the Southern Song period 南宋 (1127-1279), thus rediscovered this master, and aligned him with the genuine founders of Neo-Confucianism, the Cheng brothers.
Zhou Dunyi was convinced that literature was a mere tool to express the meaning of the Dao (wen suoyi zai dao ye 文所以載道也), and had no practical standing of its own.
Apart from the books Taiji tushuo and Tongshu, Zhu Dunyi wrote the brief text Ailianshuo 愛蓮說 on the love of flowers, as well as poems and rhapsodies, and some minor prose texts. The collected works of him are called Zhouzi quanshu 周子全書, edited by Dong Rong 董榕 (1711-1760). Another title is Zhou Lianxi ji 周濂溪集. His important philosophical texts are included in the collection Xingli daquan shu 性理大全書 by Hu Guang 胡廣 (1369-1418) and the imperial collection (Yuzuan) Xingli jingyi (御纂)性理精義 by Li Guangdi 李光地 (1642-1718) et al.