《黄帝内经·素问·五常政大论》
所以火势炎热，但随之见冰雪霜雹，其灾害应于七，所主动物为鳞虫、伏虫、猪、鼠，所主气候为冬藏之气提早而至，于是发生大寒。
炎光赫烈，则冰雪霜雹，眚于七，其主鳞伏彘鼠，藏气早至，乃生大寒。
Therefore, there is a lot of heat, but ice, snow, frost, and hail can be seen, and the disaster should be seven, and the main animals are scaly insects, dormant insects, pigs, and rats. The main climate is the early arrival of the hidden qi in winter, so there is a lot of heat. cold.