What does the idiom "take an image from money" mean?

This achievement is complete: take the image from the money, the outer circle is inside.

It means that a person should be like an ancient copper coin, with an outer circle (a person should adopt an appropriate way to deal with problems flexibly, not too rigid) and an inner circle (he should stick to his own principles and not waver).

Money carries and covers almost all the cultural information in the historical process, which is irreplaceable by any other cultural elements such as literature and art, utensils, scientific and technological inventions. For example:?

In shape, it is a round square hole. It is generally believed that it contains China's cosmology and philosophy of ancient heaven and earth, and it is the concrete embodiment of the ancient theory of Yin and Yang gossip. The philosophical ideas of "the outer circle is the inner side" and "the harmony between man and nature" advocated by him are an important part of the ancient culture of China, which has had a far-reaching impact on later generations. ?

In the unit, it was cast with face value in the early days, especially weighing coins, such as Qin Banliang and Han Wuzhu. In the Tang Dynasty, when the Kaiyuan Bao Tong coin was minted, it was no longer important. It is stipulated that every ten Kaiyuan coins weigh one or two, each Kaiyuan coin weighs one or two, and ten coins weigh one or two. This is the origin of the unit of weight "money" and the key to changing China's weighing method to decimal. Commonly known as "half a catty and eight taels" gradually lost its original meaning, and coins directly affected the implementation of measurement units and decimals. ?

In the picture decoration, characters or animal patterns are not used, but words are used. The characters on coins used to be the so-called big seal script before the Qin Dynasty, and the small seal script after the Qin Dynasty. After the Six Dynasties, official scripts were mostly used. In the Tang Dynasty, official script was used to open up Bao Tong's money. The literature and art in the Song Dynasty were unprecedentedly prosperous, which was manifested in Qian Wen's calligraphy, and it was even more colorful with different calligraphy styles. The History of Coins presents the history of ancient calligraphy in China. In addition to Chinese characters, there are various minority languages on coins minted by minority regimes, and a coin history is the complete works of ancient minority languages.