《黄帝内经·素问·至真要大论》
岐伯说：其气散而不专。所以非司岁和司岁的药物相较，形质虽同，却有等级上的差别，气味有厚薄之分，性能有躁静之别，疗效有多少的不同，药力所及也有浅深之异。
岐伯曰：散也，故质同而异等也，气味有薄厚，性用有躁静，治保有多少，力化有浅深，此之谓也。
Qi Bo said: The climate is scattered and not specialized. Therefore, medicines that do not control the year and are compared to those that do control the year, although their forms and qualities are the same, there are differences in their levels, their qi and flavors are thick or thin, their nature is irritable or calm, their therapeutic effects are different, and their medicinal power has different depths.