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The early Western Han court simultaneously accepted the philosophical teachings of Legalism, Huang-Lao Daoism, and Confucianism in making state decisions and shaping government policy. However, the Han court under Emperor Wu gave Confucianism exclusive patronage. He abolished all academic chairs or erudites (bóshì 博士) not dealing with the Confucian Five Classics in 136 BC and encouraged nominees for office to receive a Confucian-based education at the Imperial University that he established in 124 BC. Unlike the original ideology espoused by Confucius, or Kongzi (551–479 BC), Han Confucianism in Emperor Wu's reign was the creation of Dong Zhongshu (179–104 BC). Dong was a scholar and minor official who aggregated the ethical Confucian ideas of ritual, filial piety, and harmonious relationships with five phases and yin-yang cosmologies. Much to the interest of the ruler, Dong's synthesis justified the imperial system of government within the natural order of the universe. The Imperial University grew in importance as the student body grew to over 30,000 by the 2nd century AD. A Confucian-based education was also made available at commandery-level schools and private schools opened in small towns, where teachers earned respectable incomes from tuition payments.

Where did teachers make their money from at private schools?
tuition payments