What is the earliest real ancient calligraphy in China?

This is a reply. About the author: Lu Ji (AD 26 1-303) was born in Suzhou, Jiangsu, and Huating, Shanghai. He was born in a family with outstanding priests for generations. His grandfather Lu Xun and his father Lu Kang were both famous Dongwu players in the Three Kingdoms period. Lu Ji's greatest achievement in his life is writing, and he is good at literary criticism. Wen Fu, written by him at the age of 20, is the first systematic and complete speech in the history of China's literary criticism. "Reply Post" is actually a letter written by Lu Ji to a friend. The content of the article says that the disease is "difficult to calm down", so later people call it "calming paste" Ping Fu Tie has 9 lines and 84 words, which is a typical book in the evolution of cursive script. It shows a strong Cao Li style, but it is not as bright as Li Shu, and its font is between Cao Zhang and Jin Cao. Looking closely at this post, we can see that the style of this book is Gu Zhuo-style, vigorous and simple. Although the words are not connected, they are magnificent and pleasing to the eye. "Ping Fu Tie" is a bit old-fashioned and difficult to understand from words to cursive methods. When you use a pen, you use a bald pen and dry ink, just like the taste of "Long live the withered vine" pursued by some painters, which is completely different from the sweet and vulgar, showing the unique face of a bald pen. The reply is a paper book with a length of 23.8 cm and a width of 20.5 cm. At first glance, most of the calligraphy strokes are round and muddy, and the vertical pens are often inclined; The font is high on the left and low on the right, with neither a silkworm head nor a silver hook tail. However, the full text is scattered in form but not in spirit, and the strokes are self-contained, with the wave brushwork of official script; The lines are short and plump, and the strokes are simple and simple. The words used are not as continuous as today's grass, but they are not completely independent. The strokes are closely linked and echo up and down. This work combines the characteristics of Cao Zhang and Cao Jin, and its structure is natural and relaxed. It has a simple, elegant and natural style, which may be the regional calligraphy style in Wu area at that time. It has a special position in the history of the development of Chinese characters, which fully embodies the author's profound artistic accomplishment of calligraphy. As a treasure of China's calligraphy, Pingfu Post was plundered by imperialism in old China. It was during the War of Resistance against Japanese Aggression period that Japanese imperialism not only plundered China's wealth, but also turned its attention to China's ancient treasures. At the head of the national disaster, someone wants to dedicate "Ping Fu Tie" to the Japanese. At this critical moment, Zhang Boju, a great calligrapher and collector, learned about it. He was angry and anxious, and worried that this famous post would go abroad. In desperation, he sold all his possessions and bought back ancient paintings and calligraphy treasures such as Reply Post with huge sums of money. Only the "reply post" cost 40 thousand yuan. After liberation, Mr. and Mrs. Zhang Boju gave this priceless treasure and all their ancient calligraphy and paintings to the country for free, and Mao Dun, then Minister of Culture, personally presented him with a letter of commendation.