Liú Xīn 劉歆
Style name Zǐjùn 子駿 (later changed his given name to Xiù 秀 and style to Yǐngshū 穎叔 during Wáng Mǎng’s regency, to avoid taboo). Native of Péi 沛 (modern Xúzhōu 徐州, Jiāngsū). Son of 劉向 Liú Xiàng (77 BCE – 6 BCE), the great Former-Hàn bibliographer. Conventional lifedates c. 50 BCE – 23 CE. CBDB c_personid 391688 has the name without dates entered; the dates given here are the consensus of standard reference works (Loewe, Biographical Dictionary of the Qin, Former Han and Xin Periods).
The principal scholar-statesman of the late Former Hàn and Xīn regime, and one of the foundational figures of Chinese bibliography, mathematics, and astronomy. Together with his father Liú Xiàng he completed the imperial bibliographic project that produced the Biélù 別錄 and Qīlüè 七略 — the seven-section classification of the imperial library that became the structural ancestor of the Hànshū Yìwén zhì 漢書藝文志 and ultimately of all subsequent Chinese bibliographic catalogs.
In the technical sciences, Liú Xīn is the designer of the Sāntǒng lì 三統曆 (the calendar adopted by Wáng Mǎng’s Xīn 新 dynasty, preserved in the Hànshū Lǜlì zhì and reconstructed by 李銳 in KR3fc051) and the principal architect of the metrological-cosmological system relating pitch-pipe lengths, weights and measures, and calendrical constants that occupies the same Lǜlì zhì. He is also a foundational figure in the Old Text (gǔwén 古文) classical movement: his memorial advocating the inclusion of the Zuǒzhuàn 左傳, Máoshī 毛詩, Yì lǐ 逸禮 and gǔwén Shàngshū 古文尚書 among the official Academy texts is the canonical origin point of the Old / New Text controversy that dominated Hàn classical scholarship.
His political fortunes were tied to Wáng Mǎng: he served as one of Wáng Mǎng’s senior officials and ideological architects, but conspired against him in 23 CE and was executed (some sources, suicide). His mathematical-calendrical work outlived the political débâcle and entered the standard Hàn historical record.