Why is Liu Yong called Prime Minister of Thick Ink?

Liu Yong served as an official for a cabinet college student, equivalent to the "prime minister" of the Qing Dynasty. At the same time, Liu Yong is also a great calligrapher. During the Qianlong period, Weng Fanggang, Liang, Liu Yong enjoyed the reputation of being a calligrapher. At that time, people called Weng, Liang, Wang and Wei Liu "four great masters". On the artistic achievements of calligraphy, Liu Yong was the highest. So I personally infer that this is the reason why Liu Yong has this name.

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