法苑珠林 4.87

4.87

論衡曰。夫日月不圓。視若圓者。去人遠也。夫日火精。在地水火不圓。在天火何故獨圓。日月在天猶五星。五星猶列星不圓。光曜若圓。何以明之。春秋之時星霣宋都。視之如石。石也不圓。是知日月五星亦不圓也。

The Lunheng says: 'The sun and the moon are not spherical; that they appear spherical is because they are far from human beings. The sun is the essence of fire. On earth, water and fire are not spherical; why would fire alone be spherical in heaven? The sun and moon in heaven are like the five planets; the five planets are like the arrayed stars, which are not spherical, though their radiant gleam seems spherical. How do we know this? In the Spring and Autumn period, stars fell upon the capital of Song; when viewed, they were like stones, and stones are not spherical. Thus we know that the sun, the moon, and the five planets are also not spherical.'