Zheng Xuan (A.D. 127-200), born in Gaomi, was the grandson of Zheng Chong VIII, a master of Confucian classics in the Eastern Han Dynasty. He once studied Yi, Ram Chunqiu, San and Jiu Zhang Arithmetic in business studies, then studied under Zhang's Ancient History, Zhou Li and Zuo Zhuan, and finally under Ma Rong's Ancient Classics. After studying abroad, I returned to work in Donglai and gathered disciples to teach, with thousands of disciples. His family was poor and studious, and he eventually became a great scholar. The disaster of partisan struggle began, and he was imprisoned. Duman devoted himself to writing. Mainly engaged in the study of China's ancient classics, using China's modern classic theory to annotate the classics all over the world. He is the author of seven political works, including Astronomy and Loyalty, totaling more than one million words. He was called "Zheng Xue" by the world and was a master of Confucian classics in Han Dynasty.
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