东汉著名的史学家班固在《汉武故事》中,向世人讲述一个“郎潜白发”的故事。说的是,有一天,汉武帝刘彻退朝后,偶然来到郎中令官署,看到里面坐着一位须发皆白的老郎官。武帝带着几分好奇问老者:“你是什么时候担任郎官的?为什么年纪这么大了,还没有得到升迁?”老者低声回应道:“陛下,臣姓颜名泗,在文帝时就入宫为郎,至今已历三世。因为文帝主政欣赏 A famous historian in the Eastern Han Dynasty, Ban Gu, told the story of a Chinese man in the Han Wu story. That is, one day, Han Ju Di Liu Che quit after the accident, came to Langzhong government offices, saw inside a whistle-blowing officer. Wudi asked the old man with a bit of curiosity: ”When did you serve as an officer? Why old so big, have not been promoted?“ The old man whispered: ”Your Majesty, surnamed Yan Yan name Si, On the palace for the Lang, has been for three years because of the Emperor Wen dynasty admire