Impartiality (Gongzheng) or in simpler terms, fairness, is important to the progress of human beings down the ages. It forms part of human nature.
Public anger will be aroused if any person or a people is treated or deemed to be treated unfairly. There are many instances of such cases occurring during modern times not unlike happenings in ancient China. Take for instance that of Hurricane Katrina and the floods of the Yellow River. (The only difference is there were no executions of culprits in modern times.)
If rulers or their laws are not impartial not only will the people suffer needlessly, the unfairness will also make them angry. Therefore the ancient sages exhort rulers to cultivate cardinal virtues in order that public laws and taxes of the land can be fair to the multitude.
The holy sages through the Yi (Book of Changes) teach the Junzi how to cultivate these virtues, so did Confucius and Laozi in the Analects and the Tao Te Ching respectively.
According to Laozi in TTC 16, acceptance of the principle of returning to destiny leads to impartiality which in turn leads to completeness. Impartiality also relates to Centered Harmony. (To know more about centered harmony, refer to the Doctrine of the Mean).
Fellow students of the Tao and the Yi can also learn more about public sentiment on impartiality, and the cardinal virtues, by watching the Taiwanese series of the trials of Justice Bao Zheng better known as Baogong of the Song Dynasty. (Readers in Malaysia can currently follow the series, dubbed in Cantonese, shown on the Astro network on weekdays.) Any fair or impartial trial has to be based on the grounds of confirmed facts and verified evidence, and not based on mere assumptions or false beliefs.
Mere assumptions and false beliefs can lead to bypaths and not the Way.
If we do not know how to sit and forget, we cannot be empty like Heaven. If we do not cultivate virtues, we cannot be still like Earth. When we do not know how to become empty and still, can we venture to talk about the ancient Way? But people still do!
If someone is partial to Heaven and talks nothing about Earth, it would be perfectly alright to ignore his teachings, even if he happens to be an ancient sage.
Since the three great sages – Laozi, Confucius, and Buddha – taught about Heaven and Earth and so did the holy sages in the Yi. That is being impartial, and a bit more on TTC 16, if you catch the drift.