People were considered the same as animals, as expressed in the influential Qi theory, which said that people, like all things, came from Qi, and their nature differed little from the beasts: "Easy to get along with when things are good, fighting when angered, taking advantage of every chance for gain, and running away to avoid harm."
加上「氣化論」的影響，認為人與萬物都是氣之聚散，人「喜而合，怒而鬥，見利而就，避害而去」的天性，更與禽獸無異。