《文心雕龙·程器》
人附有金木水火土五种性情，但在长短上各有不同，要不是圣贤，很难苛求完备。
盖人禀五材，修短殊用，自非上哲，难以求备。
People have five kinds of temperament gold, wood, water, fire, and earth, but there are different lengths and lengths. If it is not a sage, it is difficult to be demanding for perfection.