"Xin" means to keep one's word and "zheng" means having evidence that can be checked. "Xin er you zheng" says that what a person says should not only be kept once spoken but should also stand up when set beside the facts.
The Zuo Tradition (Duke Zhao, year 8) records Shuxiang saying: "A gentleman's words are trustworthy and verifiable." The sentence uses the test of verification to tell credible speech from speech that is not.
Confucius said: "A person without good faith, I do not see how he can manage." Without trust, he said, one cannot see how a person is to live and act; Confucius thus made trust the foundation of personal conduct.
In the Western Han Dong Zhongshu named benevolence, righteousness, ritual, wisdom and trust the Five Constants, and trust passed from personal conduct into the framework of state ethics.
Trust is the class in the chapter on Values on good faith: the rule of keeping one's word and speaking what can be verified, in one's own conduct and in dealing with others. The Zuo Tradition records Shuxiang saying "a gentleman's words are trustworthy and verifiable", Confucius took trust as the foundation of personal conduct, and in the Western Han Dong Zhongshu listed it among the Five Constants.
