《淮南子·主术训》
正因为这些规定，保护了生态环境，所以草木生长如气一样蒸蒸升腾，禽兽归山如泉水一样奔流，飞鸟入林如烟云聚集，所有这些均归功于君主保护生物的措施得当。
是故草木之发若蒸气，禽兽之归若流泉，飞鸟之归若烟云，有所以致之也。
Because of these regulations, the ecological environment was protected, resulting in trees and plants growing vigorously like steam rising from a cauldron; birds and animals returning to the mountains like water gushing from a spring; and birds flying into the forest like gathering clouds and mist. All these were the result of the monarch's appropriate measures to protect animals and plants.