《论衡·卷二十二·纪妖篇》
人行走，每天不过一百里，魂与形体在一起，尚且不能走得很快，何况魂单独行走，怎么能走得快呢？
人之行，日百里。魂与体形俱，尚不能疾，况魂独行安能速乎？
People walk, and they can only walk a hundred miles a day. When the soul and the body are together, they still can't walk very fast. How can the soul walk fast when it is alone?