Yóu Yì 游藝
Style name Zǐliù 子六. Native of Jiànníng 建寧 (in modern Fújiàn). Birth and death years not securely recorded; flourished in the early-Kāngxī period (1660s-1670s).
A private Fú-jiàn-region scholar with strong interests in natural-philosophical-and-cosmographic exposition. His sole surviving work is the Tiānjīng huòwèn 天經或問 (KR3f0023), in 4 juàn (the Sìkù preserves only the Qiánjí 前集 / Earlier Collection of 4 juàn; the Hòují 後集 mentioned by the 提要 has been lost). The work is structured as a question-and-answer cosmographic primer covering the heavens-and-earth, the sun-and-moon-and-stars, eclipses, calendrical irregularities, and the meteorological phenomena of wind-cloud-thunder-lightning-rain-dew-frost-mist-rainbow.
The Sìkù 提要 praises Yóu Yì for explicitly excluding zhānyàn zhī shù 占驗之術 (divination-and-omen techniques) from the work — a “deeper recognition” (shēn shí 深識) of the proper boundary between scientific astronomy and astrological divination. The 提要 also frames the work as a corrective to the early-Qīng zhāozé (intellectual-faction) tendency to separate lìlǐ (calendrical principle) from lìshù (calendrical computation) — a tendency the editors explicitly criticize via Sūn Chéngzé 孫承澤’s Chūnmíng mèngyú lù 春明夢餘錄 (which had attributed the Yuán Shòushí lì’s success entirely to Xǔ Héng’s mínglǐ (clarifying-principle) while marginalizing Guō Shǒujìng’s measurement-and-computation). Yóu Yì’s Tiānjīng huòwèn, despite being itself somewhat weak in the technical bùsuàn (step-computation) procedures (the 提要 admits “[Yóu Yì] is also weak in step-computation”), nonetheless successfully demonstrates that jí shù jí lǐ, běn wú èrzhì “number and principle are inseparably one and the same — there is fundamentally no two-ness” — a position the 提要 holds against the kōngyán tiāndào (empty-talkers about the way of heaven) party.
The work draws substantially on the European cosmographic-and-meteorological doctrines transmitted by the late-Wànlì-and-early-Chóngzhēn Jesuits (Ricci, de Ursis, Dias, Schreck), filtered through the Chinese-language Xīnfǎ suànshū and related works. Yóu Yì himself appears to have had no direct contact with the Beijing Jesuit residence; his exposition is based on book-learning of the Jesuit-Chinese published corpus.