The two official changes in China's calligraphy are two landmark calligraphy revolutions.
(1) The first official change: from Xiao Zhuan to Li Shu.
China's calligraphy began in Oracle Bone Inscriptions, and after Qin unified China, according to the requirement of "cars on the same track, books of the same origin", Prime Minister Li Si created a standardized and unified calligraphy style "Xiao Zhuan" on the basis of six languages, and promoted it as an official calligraphy style throughout the country.
Perhaps Li Si's Xiao Zhuan is too hard to read. In fact, Qin bamboo slips, the earliest official script, came into being almost at the same time after the emergence of Xiao Zhuan, which lasted until the Three Kingdoms period.
The official script developed from bamboo slips, and the Eastern Han Dynasty was a watershed, that is, the official script before the Eastern Han Dynasty had the meaning of seal script, and the official script after the Eastern Han Dynasty began to appear, which was called "eight-part essay". In order to distinguish the "ancient writing" before the Eastern Han Dynasty, this kind of official script is also called "modern writing".
(2) The second official change: from official script to regular script and cursive script.
The second official change of calligraphy took place from the Three Kingdoms to the Wei and Jin Dynasties, which was more significant than the first official change, because this official change produced cursive script and regular script, which made a qualitative leap in the writing skills and speed of Chinese characters and was an important revolution in the history of calligraphy culture.
The evolution from official script to cursive script is not the content involved in this topic. Let's just talk about the emergence of regular script here for the time being.
The transition from official script to regular script experienced the transitional style of Weibei. Lishu developed to the Northern Wei Dynasty, and calligraphy began to develop to Fang Bi's angular calligraphy. Horizontal painting no longer emphasizes "silkworm head and goose tail", but the brushwork of lifting pressure appears. Basic strokes such as skimming, lifting and hooking are much more complicated and rich than the original official script.
The development of Weibei to the Western Jin Dynasty, or the era of Wang Xizhi, has basically taken shape. For example, at this time, Wang Xizhi's small script has basically broken away from the official script, and a brand-new regular script image has appeared.
Regular script developed in the Tang Dynasty and reached its peak. Today, Tang calligraphy is still the highest level of regular script development.