Li Chunfeng

Li Chunfeng (simplified Chinese: 李淳风; traditional Chinese: 李淳風; pinyin: Lǐ Chúnfèng; Wade–Giles: Li Ch'un-feng) (602–670) was a Chinese mathematician, astronomer, and historian who was born in today's Baoji, Shaanxi during the Sui and Tang dynasties. He was first appointed to the Imperial Astronomy Bureau to help institute a calendar reform. He eventually ascended to deputy of the Imperial Astronomy Bureau and designed the Linde calendar. His father was an educated state official and also a Taoist. Li died in Chang'an in 670.

The Sui Dynasty was integral for uniting China, so it was a good time for learning. But when Li was sixteen the Sui fell, and the Tang rose. Nevertheless, the Tang did not harm the conditions for education. Indeed, it rather strengthened it. The Imperial Academy's math teaching was formalized. He was appointed into the Imperial Astronomy Bureau as an advanced court astronomer and historian, in 627. Once several years had passed, he then was promoted to deputy director of the Imperial Astronomy Bureau in 641, and even director in 648. He was given these titles because the Chinese calendar of the era, despite that it had only been used for several years, was already having accuracy problems in predicting eclipses. In fact, Li was appointed partially because of his critique of the Wuyin calendar. Wang Xiaotong had been chosen to study the problem earlier. This was a very important job because of the Chinese belief in the Mandate of Heaven. So if one altered the calendar, that person would have some control over the connection between the heavens and the emperor.

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