Chinese characters were created by ancient Chinese based on the 'pictographic symbols'. Consequently, the model of 'Imagery' has been popular in calligraphy criticism since ancient China. However, new critical views proposed by Mi Fu and Zhu Changwen, which focused more on clarity than rhetoric, came into being in the Song Dynasty. These views were echoed by contemporary calligraphy monographs which advocated the style of simplicity and clarity. There are various causes for this phenomenon. The exogenous cause is the popularization of knowledge and the Ancient Prose Movement launched by Liu Kai and Ouyang Xiu. As an endogenous cause, the pictographic element had declined with the maturity of Chinese characters, and the ambiguity and uncertainty caused by 'Imagery' became unfavorable for the appreciation and inheritance of calligraphy. In sum, it may be said that the decline of 'Imagery' is a historical inevitability as well as a good progress in the history of Chinese calligraphy.