《论衡·卷十八·自然篇》
天地，如同夫妇，地体没有口目，也就知道天没有口目了。
无地，夫妇也，地体无口目，亦知天口目也。
Heaven and earth are like husband and wife, the body of the earth has no mouth and eyes, so you can also know that the celestial vault has no mouth and eyes.