The Planetary Model In Xinfa Suanshu And Its Interpretations By Chinese Scholars At The Early Qing Dynasty

During the late Ming Dynasty, the errors of the Datong calendar (大统历) became increasingly obvious, while the traditional Chinese astronomy had declined to such a level that nobody any longer knew its principles. Under such circumstance, a few cultural elite such as Xu Guangqi and Li Zhizhao cried for reforming the calendar vehemently and recommended the Jesuits such as Matteo Ricci, Nicolas Longobardi and Johann Terrenz to join in the affairs. The court at last accepted the Jesuits to undertake the calendar reform under the supervision of Xu Guangqi. After five years arduous efforts, the Chong Zhen Li Shu(崇祯历书)-- more than one hundred volumes in which Western astronomy is comprehensively introduced– was compiled. On the basis of Li Shu, the new calendar also came out. Unfortunately, during the transitional period from the Ming Dynasty to the Qing Dynasty, Li Shu was not published, and the new calendar was also not issued officially. It was not until Shunzhi's first year, when Johann Adam Schall von Bell revised Chong Zhen Li Shu to Xi Yang Xin Fa Li Shu (西洋新法历书)and devoted it to the Qing court, that Li Shu (the revised version) was printed through out the empire. Since then, it became the textbook of western astronomy for Chinese literate and produced strong influence on the intellectual currents of the Qing Dynasty. During the reign of Qianlong Emperor, Xi Yang Xin Fa Li Shu was again revised and renamed as Xin Fa Shuan Shu (新法算书)and gathered into the encyclopedia Si Ku Quan Shu(四库全书).The thesis attempts to reconstruct the planetary model for the Sun, the Moon and the superior planet, the Saturn, in Xin Fa Shuan Shu with modern terminology. Specifically, it involves the historical perspective of western planetary astronomy, the method for the determination of parameters and the procedure for the calculation of prothaphaeresis in each planetary model. On the basis of historical interpretation, the thesis differentiated those mixed models adopted by Xin Fa Shuan Shu according to three categories—the Ptolemiac, the Copernican and the Tychonic model, supplemented some missed links in Xin Fa Shuan Shu such as the procedure for the calculation of prothaphaeresis of the Tychonic model for the Moon, and thus obviated the difficulties for the further study of (月离表). Consequently, the thesis presented a whole landscape for the movement models of the Sun, the Moon and five planets introduced into China by the Jesuits.Inspired by Western cosmological system presented in Xin Fa Shuan Shu, Chinese scholars in early Qing Dynasty began to annotate and elaborate it with huge volumes. Western cosmological model achieved prominent success in"saving the phenomena", but it was content with Aristotelian physics and to some extent shunned to discuss the dynamical mechanism of celestial body. In contrast, Chinese cosmology placed much emphasis on the dynamical mechanism as was showed in the continuous controversy on the rotational direction of the Sun and the Moon in the Song and Yuan Dynasty, and to the large extent neglected to explain the celestial phenomena. During the late Ming and early Qing Dynasty, Chinese astronomer resumed to elaborate the left/right rotational mechanism. They not only tried to supply Western geometrical model with certain dynamical account, but also attempted to borrow the concept of"seven celestial bodies located at different spheres"from Western astronomy into Chinese debates on the rotational direction. Based on the comparative study of Western and Chinese cosmology, the thesis also discussed the possible reasons why Wang Xichan and Mei Wending adopted different attitudes towards the rotational directions of celestial bodies.Wang Xichan was one of the foremost Chinese scholars who achieved a thorough understanding of Xin Fa Shuan Shu. On the basis of his careful studies, including as well his own astronomical observations, he set out to realize Xu Guangqi's plan– to reinterpret the content of the Western calendar in the form of the Datong calendar. His Xiao An Xing Fa(晓庵新法) was just such a book. In response to Western cosmological model, he also wrote three important treatises, Li Shuo V (历说·五), Wu Xing Xing Du Jie (五星行度解), and Ri Yue Zuo You Xuan Wen Da (日月左右旋问答). In chapter five of this thesis, the author discussed once again the planetary theory for the Sun, the Moon and five planets in Xiao An Xing Fa and quasi-Tycholic system in Wu Xing Xing Du Jie, pointed out the inherent relation between them, and solved several long standing problems such as the reason why Wang Xichan reversed the rotational direction of three superior planets from right to left and why he changed the geometrical orbits into physical entities. Thus, the inherent consistency and relative progress of Wang Xichan's astronomical work compared with Xin Fa Shuan Shu is revealed.