These were two types of writing in ancient times aimed at criticizing errors, upholding virtue, and inspiring philosophical thought. Ming (铭), meaning epigraph, is a brief account of merits and virtues inscribed on a vessel. Its sacredness and exemplary nature means such writing should be aspirational and visionary. Zhen (箴), meaning maxim, on the other hand, is intended to admonish or warn. In Chinese, it is pronounced as zhen, meaning an acupuncture needle, a traditional device for preventing or curing disease. Therefore, a zhen, should perform the role of preventing an error. Both ming or an epigraph and zhen or a maxim aim to admonish people against evildoing, promote virtue and punish vice. In the view of Liu Xie (465?-520) of the Southern Dynasties, both types of writing should offer true and reliable information and convincing arguments and be succinct in wording and profound in significance.

Thus, ming, meaning “inscription” here is equivalent to appellation. When examining a utensil or an artifact, one should name it on the basis of its nature. The purpose of such scrutiny is to promote moral behavior. (Liu Xie: The Literary Mind and the Carving of Dragons)

Zhen here means to perform acupuncture for a curative effect. To offer a maxim is, like using an acupuncture needle, to criticize wrongdoing to prevent a disaster. (Liu Xie: The Literary Mind and the Carving of Dragons)

Zhen, or maxim, is cited by an official to advise the emperor face to face, whereas ming, or epigraph, is inscribed on a vessel. Although different in name, they both perform a function of admonition. Zhen is used mainly to prevent an error, so it should rely on factual presentation and be precise in wording. Ming, on the other hand, also commends fine deeds, so it should be profuse and elegant in style. All the instances cited should be perfectly reliable and can stand up to close scrutiny. They should be concise and exert a profound social influence. These are the basic rules for writing ming or zhen. (Liu Xie: The Literary Mind and the Carving of Dragons)