《黄帝内经·素问·六元正纪大论》
三之气，主气为少阳相火，客气为太阳寒水，司天之气布其政令，寒气大行，雨乃降下。
三之气，天政布，寒气行，雨乃降。
The air of the third step, the main air was the Shao Yang phase fire, the objective air was the sun and cold water, the air of presiding over the government of heaven governed its decree, cold air prevailed, rain fell.