《贞观政要·卷五·论诚信》
信任对于治理国家至关重要。过去，齐桓公对管仲说： 我想使酒在酒器中变坏，肉在锅中腐烂，这样做对治国无害吧？ 管仲说： 这样做不好，但对治国也无害。 齐桓公问： 那么什么会危害国家呢？ 
上不信，则无以使下，下不信，则无以事上，信之为道大矣。昔齐桓公问于管仲曰： 吾欲使酒腐于爵，肉腐于俎，得无害霸乎？ 管仲曰： 此极非其善者，然亦无害于霸也。 桓公曰： 如何而害霸乎？ 
Trust is a vital element in the government of a country. Of old, Duke Huan of Qi said to Guan Zhong: "I wish to make the spirits change and the flesh rot: would this harm my government?" Guan Zhong said: "It would not be well, but still it would not harm your government." Duke Huan said: "What then would harm my government?"