Wùshēn lìchūn kǎozhèng 戊申立春考證
A Verification of the Lichun (Beginning of Spring) of the Wushen Year by 邢雲路 (撰)
About the work
The Wùshēn lìchūn kǎozhèng 戊申立春考證 is a focused empirical demonstration by the late-Wàn-lì commoner-astronomer Xíng Yúnlù 邢雲路 (jìnshì 1580) that the Míng official Dàtǒng lì 大統曆 was systematically out of step with observation: at the lìchūn 立春 (start-of-spring node) of the wùshēn 戊申 year — Wànlì 36 (1608) — the calendar’s predicted node fell hours away from the observed gnomon-shadow node. The work formed the empirical centrepiece of Xíng’s larger campaign for calendrical reform and was deployed as the practical demonstration of the more comprehensive critique developed in his Gǔjīn lǜlì kǎo 古今律曆考 (KR3f0008).
Abstract
The opening text is a third-party preface — the writer recalls seeing Xíng’s Lǜlì kǎo 律曆考 in the bǐngwǔ 丙午 year (Wànlì 34 / 1606) at Shàngjùn 上郡 in northern Shǎnxī, then having the work in hand the following year while travelling through Jìnzhōng 晉中 (central Shānxī). The preface enumerates in detail the contents of the parent work’s Lìyì 曆議 and Lìyuán 曆原 in 13 juàn: critiques of the Yuán Shòushí lì and the Míng Dàtǒng lì on (i) handling of the polestar; (ii) suìyú 歲餘 and suìchā 歲差; (iii) rìchán 日躔 (solar position); (iv) yuèlí 月離 (lunar elongation); (v) the white-path and node calculations; (vi) eclipse limits; (vii) the planets, with special attention to the 20-day error in the Mercury motion; and (viii) the propagation of the huánggōng 黃宮 / gōngchā 宮差 errors into the secondary divinatory systems (qīzhèng sìyú 七政四餘, tàiyǐ 太乙, liùrén 六壬, qímén dùnjiǎ 奇門遁甲, xīngmìng 星命, yīnyáng 陰陽, bǔshì 卜筮).
The Wùshēn lìchūn kǎozhèng itself is then presented as the empirical confirmation of these theoretical criticisms: observation at the lìchūn of wùshēn — Wànlì 36 (1608) — shows the Dàtǒng lì’s prediction to be in error, vindicating the larger corrective programme of Gǔjīn lǜlì kǎo. NotBefore is set at 1608 (the wùshēn observation itself); notAfter at 1610 (consistent with the preface’s reference to seeing the parent work bǐngwǔ–dīngwèi 1606–07 and to the demonstration of wùshēn 1608, and prior to Xíng’s 1611 court memorialisation of the matter).
Xíng Yúnlù’s broader role in the late-Wàn-lì calendrical reform agitation is documented in his person note: he was the leading independent calendrical critic of the period, his agitation alongside Zhū Zàiyù’s KR3f0007 and Lǐ Zhīzǎo’s the indispensable lobbying that ultimately produced the Chóngzhēn lìshū reform initiative of 1629.
Translations and research
- 陳美東 Chén Měidōng. 1986. Gǔ-lì xīn-tàn 古曆新探. Shěn-yáng: Liáo-níng jiāo-yù chū-bǎn-shè. — Sustained treatment of Xíng Yún-lù’s calendrical critique.
- 石雲里 Shí Yún-lǐ. Several papers on Xíng’s gnomon observations and the suì-shí 歲實 (tropical year) measurement programme.
- Hashimoto Keizō 橋本敬造. 1988. Hsü Kuang-ch’i and Astronomical Reform. Suita: Kansai University Press. — Background on the late-Míng reform agitation.
- Jami, Catherine. 2012. The Emperor’s New Mathematics. Oxford: Oxford University Press.
- 陳美東 Chén Měidōng. 2003. Zhōngguó kēxué jìshù shǐ: Tiān-wén-xué juǎn 中國科學技術史·天文學卷. Beijing: Kē-xué chū-bǎn-shè.
Other points of interest
Xíng Yúnlù’s dating of the wùshēn observation precisely localises this work to Wànlì 36 / 1608, an unusually crisp date for a calendrical-reform polemic. The fact that the third-party preface is signed in “Jìnzhōng” 晉中 — central Shānxī — corresponds to Xíng’s tenure as Magistrate of Línfén 臨汾 (Shānxī) and Vice Provincial Surveillance Commissioner of Shǎnxī, the Shānxī posts on which most of his observational work was carried out.