Bǔxiū Sòng Fèngyuán shù 補修宋奉元術
Supplementary Reconstruction of the Sòng Fèng-yuán Calendar by 李銳 (述并注)
About the work
李銳 Lǐ Ruì’s (1768–1817) supplementary evidential reconstruction in 1 juàn of the Fèngyuán lì 奉元曆, the official calendar of the Northern Sòng promulgated under Shénzōng 神宗 in Xīníng 熙寧 7 (1074), used for nineteen years until replaced by Wáng Sōng’s 王宋 Guāntiān lì 觀天曆 in 1093.
Abstract
The Fèngyuán lì was designed by Wèi Pǔ 衛朴 and a commission of imperial astronomers in response to the discovery of significant errors in the preceding Northern-Sòng calendrical system. It was adopted in Xīníng 7 (1074). The system was technically conservative — incremental refinement of the Chóngtiān lì 崇天曆 of 1024 — but introduced revised values for the fundamental mean-motion constants and revised eclipse procedures.
The Fèngyuán lì survives in summary form in the Sòngshǐ Lǜlì zhì 宋史律曆志, but the algorithmic procedures are less fully preserved than those of the leading Sòng calendars (the Tǒngtiān 統天 of Yáng Zhōngfǔ 楊忠輔 and the Shòushí 授時 of 郭守敬 Guō Shǒujìng). Lǐ Ruì’s 1-juàn reconstruction is explicitly bǔxiū 補修 (“supplementary reconstruction”) — filling out the algorithmic detail from the abbreviated Sòngshǐ presentation, drawing on parallel evidence from the preceding Chóngtiān and the following Guāntiān systems. The companion 1-juàn reconstruction of the Zhàntiān lì 占天曆 (in KR3fc055) does the same for one of the supplementary Northern-Sòng calendars.
The pair is the Sòng tail of Lǐ Ruì’s five-work calendrical sequence (KR3fc051–KR3fc055), extending his evidential-philological method from the Hàn calendrical foundations forward to the high-period Sòng systems. The systematic QiánJiā recovery of the historical Chinese calendrical tradition that the sequence represents was the technical-mathematical complement to the broader QiánJiā evidential project on the classical and historical canons.
Dating: composed during Lǐ Ruì’s mature productive period in 阮元 Ruǎn Yuán’s patronage circle. notBefore 1795; notAfter 1817.
Translations and research
- Sivin, Nathan. 2009. Granting the Seasons: The Chinese Astronomical Reform of 1280. New York: Springer. — Principal modern study of the Sòng-Yuán calendrical tradition.
- Qū Ānjīng 曲安京. 2005. Zhōng-guó lì-fǎ yǔ shù-xué 中國曆法與數學. Běi-jīng: Kē-xué chū-bǎn-shè.
- Wú Wénjùn 吳文俊, ed. 1985. Zhōng-guó shù-xué shǐ dà-xì 中國數學史大系, vol. 7.
Links
- Companion reconstructions: KR3fc051–KR3fc053 (Hàn), KR3fc055 Bǔxiū Sòng Zhàntiān shù
- CBDB (author): https://cbdb.fas.harvard.edu/cbdbapi/person.php?id=77136