Use a pen in your heart, your heart is regular, and your pen is correct. This refers to calligraphy, which means to write with your heart. Only by using your heart correctly can you write good words.
Mu Zong asked Liu Gongquan how to use a pen, and Gong Quan replied: Use a pen in your heart, your heart is always there, and your pen is correct. When Mu Zong was lonely, he changed his face and realized his own remonstrance.
Interpretation: The original meaning is calligraphy. You should write with your heart. As long as the mentality is correct, writing is a good word. In fact, it is a metaphor, saying that the emperor should be upright and do things that benefit the country and the people. It can also be extended to being a man and doing things, having a correct heart and acting naturally.
Liu Gongquan is a summarizer and innovator of regular script. On the basis of learning and inheriting the regular script styles of Zhong You, Wang Xizhi and others, he read modern calligraphy, learned from Yan Zhenqing, absorbed his new ideas, and created his own unique "six-style" regular script, which was imitated by later generations and became one of the outstanding representatives of "Tang Shu Shang Fa".
His handwriting is even, thin and hard, and he pursues Wei Bei firmly. His stippling is crisp and beautiful, with thick bones and tight body. "Books are expensive, thin and hard, and the spirit is clear." Compared with his face, his regular script is slightly flat and thin, so it is called "Yan Gu".