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Cheng Yi

1033–1107

A first way ina deliberate simplification – the portrait says more

One principle runs through all things in countless forms, and we come to know it by investigating things carefully, one after another.

Placement

East Asian Philosophy · East Asia · Metaphysics, Ethics, Epistemology

Younger of the Cheng brothers: principle is one, its manifestations many; it is known by investigating things one by one – the root of the Cheng–Zhu school.

Key ideas

  • Principle is one, manifestations many
  • Investigation of things
  • Reverence (jing)

Teachers: Zhou Dunyi

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Influence

Influenced by 3

  • Mengzi (Mencius)

    influenced by

    Cheng Yi upheld Mencius’ thesis that human nature is good by identifying the nature with principle and tracing evil to the endowment of material force (qi). Er Cheng yishu; W.-t. Chan, A Source Book in Chinese Philosophy (1963)

    Evidence: AI draft

    Mengzi (Mencius) › c. 372–289 BCE

  • Zhou Dunyi studied with

    studied with

    Attested in the brothers’ recorded sayings (a remark about once studying with Zhou Maoshu, Henan Chengshi yishu 2A), which do not say which brother is speaking; that Cheng Yi studied there with his brother as a boy is stated by Zhu Xi, who also made Zhou the founder of their school. Henan Chengshi yishu 2A (recorded by Lü Dalin); Zhu Xi, Yichuan xiansheng nianpu

    Evidence: AI draft

    Zhou Dunyi › 1017–1073

  • Zhang Zai

    influenced by

    Defending Zhang Zai’s Western Inscription against Yang Shi’s charge of Mohist universal love, Cheng Yi read it as teaching that principle is one but its manifestations many. Cheng Yi, reply to Yang Shi on the Ximing, in Er Cheng wenji; W.-t. Chan, A Source Book in Chinese Philosophy (1963)

    Evidence: AI draft

    Zhang Zai › 1020–1077

Influenced 2

  • Zhu Xi

    influenced

    Zhu Xi adopted Cheng Yi’s theses that the nature is principle and that investigating things means probing principle, the latter in his supplement to the Great Learning (1189). Zhu Xi, Daxue zhangju (preface 1189), supplement on the investigation of things; W.-t. Chan, A Source Book in Chinese Philosophy (1963)

    Evidence: also in InPhO · InPhO

    Zhu Xi › 1130–1200

  • Feng Youlan

    influenced

    Feng Youlan’s History of Chinese Philosophy (1934) made Cheng Yi, not his brother, the founder of the learning of principle that Feng renewed in Xin lixue (1939). Feng Youlan, Zhongguo zhexue shi (1931–34), tr. D. Bodde (1952–53); Xin lixue (1939); IEP “Feng Youlan”

    Evidence: AI draft

    Feng Youlan › 1895–1990

Criticism

Criticized by 1

  • Dai Zhen

    criticised by

    Dai Zhen charged that the Cheng–Zhu principle (li), set apart from human desires, had let the powerful put people to death in the name of principle (Mengzi ziyi shuzheng, 1777). Dai Zhen, Mengzi ziyi shuzheng (1777), tr. A. Chin & M. Freeman, Tai Chen on Mencius, 1990

    Evidence: AI draft

    Dai Zhen › 1724–1777

Works

Position

Cheng Yi gave Neo-Confucianism its classic framework. Principle (li) is one, its manifestations many: every thing has its principle, all principles are ultimately one, and human nature is principle (xing ji li), while differences in vital force (qi) account for good and bad conduct. Principle is known by investigating things – one today, another tomorrow – until understanding suddenly becomes comprehensive. Cultivation requires reverence (jing), learning the extension of knowledge. Zhu Xi followed him so closely that one speaks of the Cheng–Zhu school. Later critics made him a symbol of rigid morality, not least for his remark that for a widow starving is a small matter beside losing her chastity.

Life & context

Cheng Yi, known as Yichuan, was born in 1033, the younger brother of Cheng Hao. At the Imperial Academy he won attention with an essay on what Confucius’ disciple Yan Hui loved to learn. He long declined office and taught in Luoyang; in 1086 he became lecturer to the young emperor but soon fell victim to factional strife. Banished in 1097, pardoned in 1100, he died in 1107.

Further main works

  • What Master Yan Loved to Learn (Yanzi suo hao he xue lun, c. 1056)
  • Surviving Works of the Two Chengs (Er Cheng yishu, compiled by Zhu Xi, 1168, posthumous)

Sources: Wikipedia · Wikidata

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