《黄帝四经·称经·全文》
天属阳而地属阴，春属阳而秋属阴，夏属阳而秋属阴，白天属阳而黑夜属阴，大国属阳而小国属阴，强国属阳而弱国属阴，做事属阳而无为属阴，伸展属阳而屈缩属阴。
天阳地阴，春阳秋阴，夏阳冬阴，昼阳夜阴，大国阳，小国阴。重国阳，轻国阴。有事阳而无事阴。信者阳而屈者阴。
Heaven belongs to Yang and earth belongs to Yin, spring belongs to Yang and autumn belongs to Yin, summer belongs to Yang and autumn belongs to Yin, day belongs to Yang and night belongs to Yin, a big country belongs to Yang and a small country belongs to Yin, a strong country belongs to Yang and a weak country belongs to Yin, doing things belongs to Yang and doing nothing belongs to Yin, stretching belongs to Yang and shrinking belongs to Yin.