Yu Xi
Yu Xi (虞喜; fl. 307-345 AD), courtesy name Zhongning (仲寧), was a Chinese official, scholar, and astronomer of the Jin Dynasty (265-420 AD).
Background and official career
The life and works of Yu Xi are described in his biography found in the Book of Jin, the official history of the Jin dynasty.[1] He was born in Yuyao, Guiji (modern Shaoxing, Zhejiang province, China). His father Yu Cha (虞察) was a military commander and his younger brother Yu Yu (虞預; fl. 307–329 AD) was likewise a scholar and writer. During the reign of Emperor Min of Jin (r. 313-317 AD) he obtained a low-level position in the administration of the governor of Guiji commandery.[2] He declined a series of nominations and promotions thereafter, including a teaching position at the imperial university in 325 AD, an appointment at the imperial court in 333 AD, and the post of cavalier attendant-in-ordinary in 335 AD.[1]
Works
In 336 AD Yu Xi wrote the An Tian Lun (安天論; Discussion of Whether the Heavens Are At Rest or Disquisition on the Conformation of the Heavens).[3] He described the precession of the equinoxes (i.e. axial precession).[4] He also wrote a critical analysis of the huntian (渾天) theory of the celestial sphere,[1] arguing that the heavens surrounding the earth were infinite and motionless.[4] Yu Xi advanced the idea that the shape of the earth was either square or round, but that it had to correspond to the shape of the heavens enveloping it.[4] The huntian theory, as mentioned by Luoxia Hong (fl. 140-104 BC) and fully described by Zhang Heng (78-139 AD), insisted that the heavens were spherical and that the earth was like an egg yolk at its center.[5] Yu Xi's ideas about the infinity of outer space seem to echo Zhang's ideas of endless space even beyond the celestial sphere.[4]
Yu Xi is also known to have written commentaries on the various Chinese classics.[1] His commentaries and notes were mostly lost before the Tang dynasty, but the fragments preserved in other texts were collected in a single compendium by Qing-dynasty scholar Ma Guohan (1794-1857).[1]
See also
Citations
- ^ a b c d e Knechtges and Chang (2014), p. 2010.
- ^ Knechtges and Chang (2014), p. 2009.
- ^ The first English rendering is given by Needham and Ling (1995), p. 220, whereas the second translated title is provided by Knechtges and Chang (2014), p. 2010.
- ^ a b c d Needham and Ling (1995), p. 220.
- ^ Needham and Ling (1995), pp. 216-217.
References
- Knechtges, David R.; Chang, Taiping. (2014). Ancient and Early Medieval Chinese Literature: a Reference Guide, vol 3. Leiden: Brill. ISBN 978-90-04-26788-6.
- Needham, Joseph; Wang, Ling. (1995) [1959]. Science and Civilization in China: Mathematics and the Sciences of the Heavens and the Earth, vol. 3, reprint edition. Cambridge: Cambridge University Press. ISBN 0-521-05801-5.