《论衡·卷十一·说日篇》
日月合在一起，互相重迭，月亮在上面，太阳在下面，无法遮住太阳；太阳在上面，月亮在下面，太阳被月亮遮住了，月亮也遮住了阳光，所以称作 食 。太阳遮住月亮，就像阴云遮蔽了日月看不见一样。
日月合相袭，月在上日在下者，不能掩日。日在上，月在日下，障於日，月光掩日光，故谓之食也，障於月也，若阴云蔽日月不见矣。
The sun and the moon are combined and overlap each other, the moon is above, and the sun is below, which cannot cover the sun; the sun is above, and the moon is below, the sun is covered by the moon, and the moon also covers the sunlight, so it is called eclipse. The sun covers the moon, just like the overcast clouds cover the sun and the moon and cannot be seen.