三谈《周髀算经》中的盖天说

A FURTHER DISCUSSION ON THE GAITIAN THEORY IN ZHOU BI SUAN JING

本文同迄今为止的流行观点相反,认为盖天说比浑天说先进。这是因为:盖天说已经识破天地相连的假象,发现天地相互平行,因而有利于发展地圆观点;已经知道天上和地面上都有北极、赤道和南北回归线,因而有条件提出地理地带的概念;已经发现地面分为白昼区和黑夜区,并且力图解决白昼区的大小问题,凡此都先进于浑天说。

This article suggests that the Gaitian Theory is more advanced than the Huntian Theory for the following reasons: (1) The former recognizes that the heaven and the earth are apart from and parallel with each other, and so it is conducive to the establishment of the roundearth concept, but the latter does not. (2) The former discovers that the earth is always divided into a day-area and a night-area and attempts to know the diameter of the day-area, but the latter knows nothing about this. (3) The former is aware of the existence of the north pole, the equator and the tropics on the earth surface, and is thus able to propose the Concept of geographical belts, whereas the latter does not know anything about this.