《吕氏春秋·纪·仲秋纪》
蛰伏的动物都藏在洞穴口。冬阴之气渐渐旺盛，阳气日新衰触，水开始干涸了。
杀气浸盛，阳气日衰，水始涸。
The hibernating animals all keep to the mouths of their holes. The Cold of winter gradually increases, while the Yang energy becomes daily more feeble. The water begins to dry up.