《黄帝内经·素问·六微旨大论》
所以说：天枢以上，天气主之，天枢以下，地气主之；在气交之处，人气顺从天地之气的变化，万物由此而生。
故曰： 天枢之上，天气主之；天枢之下，地气主之；气交之分，人气从之，万物由之。 
Therefore it is said: Tianshu and above, weather qi is in charge, Tianshu and below, earth qi is in charge; in the place of qi exchange, human qi follows the changes to the heavenly qi and earth qi, from which all things are born.