《资治通鉴·汉纪·汉纪三十四》
刘秀喜好运用隐语或预言占验吉凶的图谶，和郑兴讨论到郊外祭祀的事，说： 我想用图谶来推断，怎么样？ 
帝好图谶，与郑兴议郊祀事，曰： 吾欲以谶断之，何如？ 
Liu Xiu enjoyed using secret language or the Tai Xiang, a kind of picture prophecy, to predict good or bad fortune. He discussed the matter of sacrificing to the suburbs with Zheng Xing, saying, "I intend to use the Tai Xiang to make a prediction, what do you think?"