This sentence comes from "Liu Gongquan's calligraphy practice"
Introduction to the story:
Liu Gongquan was often criticized by his teacher and father for his poor handwriting when he was a child. He listened to their teachings with an open mind. After a year of hard work, his calligraphy has made great progress and was praised by the teacher. The number of praises has increased, and Liu Gongquan also feels great. One day, Liu Gongquan and several friends held a big print writing competition.
He quickly wrote an article, thinking that he would definitely win the championship, and his face showed a smug look. An old man selling tofu saw that Liu Gongquan was so immodest and wanted to throw some cold water on him. He went up to him and said, "There is a man who writes with his feet in Huayuan City, and he writes better than you." Liu Gongquan was a little unconvinced and arrived at Huayuan City early the next morning.
He saw with his own eyes that the old man with a broken arm was pressing the paper lying on the ground with his left foot, and his right foot was holding a writing brush. He was writing couplets while flying, and the words he wrote were many times better than those he didn't know. He calmed down and thought his little achievements were nothing. He sincerely said to the armless old man, "Liu Gongquan is willing to worship you as a teacher and ask the teacher to tell the students the secret of writing."
The armless old man pondered for a moment and wrote him four sentences: "Write eight jars of water, and the inkstone will blacken the waterlogged pool, and the dragon and phoenix will win over a hundred parents before flying."
The old man explained, "This is the secret of my writing. I have practiced writing with my feet for more than 50 years. I used eight cylinders of water mill ink to practice calligraphy. After writing every day, I wash the inkstone in a pond of half an acre, and the water in the pond is dyed black. But the sky is behind, the mountains are behind, and my handwriting is far from perfect! " Liu Gongquan firmly remembered the old man's words. Since then, he has practiced calligraphy more diligently.
Liu Gongquan is a summarizer and innovator of regular script. On the basis of learning and inheriting the regular script styles of Zhong You and Wang Xizhi, 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".
Since the end of Tang Chaoyuan, Liu Gongquan's reputation has become higher and higher. Emperor Xuanzong of the Tang Dynasty especially cherished Mo Bao of Liu Gongquan. Liu Gongquan was called to the front of the temple, and the military commander ordered Simon Xuan Ji to hold the inkstone, and the Tang Dynasty envoy Cui Juyuan wrote it. Liu Gongquan wrote the cross of "Mrs. Wei's brushwork" on a piece of paper with a real book. On a piece of paper, he wrote eleven words, "A thousand words are true grass, the family law of Yongchun Temple".
On a piece of paper, I wrote "How can predicates help others?" Xuanzong gave him brocade, bottles and jars and other silverware. And let him write a thank-you letter, whether it is a real book or a cursive script.
At that time, the minister's family set up a monument to his ancestors. If there is no inscription by Liu Gongquan, people will think it is unfilial. Moreover, Liu Gongquan's reputation spread far and wide overseas. When he went abroad to pay tribute, he specially prepared money to buy Liu Gongquan's calligraphy. Tang Wenzong once praised his calligraphy, even the rebirth of Zhong You and Wang Xizhi.
Baidu Encyclopedia-Liu Gongquan