1, we started from Oracle Bone Inscriptions, the ancestor of Chinese characters. In Oracle Bone Inscriptions, we can see the word "row" written on the outside of the word "de", which is an pictograph, referring to the crossroads, just like our current crossroads. In the middle of Oracle Bone Inscriptions's word "virtue" is the image of eyes, and a straight line is drawn above the eyes, indicating that people should see the direction clearly when walking, and walk in the middle of the road to avoid encountering sundries or wrestling.
2. In the bronze inscriptions of the Zhou Dynasty, a word "heart" was added under the eyes, which obviously means that not only the eyes should be straight, but also the heart should be straight. Although the eyes are staring straight ahead, it is still easy to have an accident mentally. As can be seen from the writing of the word "de" above, the word "line" other than the word "de" has changed from completely left and right to only one side, and from complexity to simplicity.
Let's look at the writing of the word "de" in official script. The first one in the above picture is written in silk script, which is also the handwriting of official script in Han Dynasty. The last exaggeration of the word "heart" shows that the aesthetic consciousness of calligraphy has been greatly improved. We can also see that the two sides of the word "De" are sometimes written as one side, and a horizontal picture is added between the two official scripts.
There is a horizontal picture between seal script and official script in Qing dynasty. Let's take a look at the writing of the word "de" in Weibei. Weibei is the font of the Southern and Northern Dynasties. Jia Qiang found a horizontal picture in the middle of the word "de" in the Southern and Northern Dynasties. It is the third word in the picture above.
5. The third word in the above picture is the word "De" in Wang Xizhi's "Monument to the Filial Piety", and there is a horizontal picture in the middle. Therefore, from the Wei and Jin Dynasties, the word "de" gradually evolved into an additional horizontal painting. Judging from the above two words with horizontal paintings, it should be to supplement the blank.