It is in the nature of the flower to fade and wither, but "fallen flowers are not unfeeling, for they turn to Spring earth and protect [the next generation of] flowers." Thus people of the Song discovered flowers 'continued existence after death, and the illusory nature of color.
因此花的本質其實是從有到無，「落紅不是無情物，化作春泥更護花」，宋人發現了花在消失之後的存在，以及顏色的幻滅性。