This is the immortal famous saying of Zhang Zao, a painter in the Tang Dynasty. These eight words sum up the whole process of objective phenomenon-artistic image-artistic image. In other words, art must come from the beauty of reality and take the beauty of reality as its source. But this kind of realistic beauty must be melted and recreated by the painter's subjective feelings before it becomes artistic beauty. It must be the organic unity of the form and spirit of objective reality and the painter's subjective feeling. The objective reality reflected in the works must be branded with the painter's subjective feelings. Zhang Zao briefly broke all the secrets of the formation of artistic image in one sentence, and even spread to this day, lasting forever.