《宋史·列传·卷一百九十六》
杜范力言郑清之误国，认为其贪婪狡诈较史弥远更为严重。真德秀则认为 ：追根溯源，还是史弥远擅权所造成的恶果，这与扁鹊继庸医之后，一药之误，便代为庸医受责是一样的道理。 真德秀之议论与杜范看法之不同由此可见一斑。
杜范方攻清之误国，且谓其贪黩更甚于前，而德秀乃奏言： 此皆前权臣玩悽之罪，今日措置之失，譬如和、扁继庸医之后，一药之误，代为庸医受责。 其议论与范不同如此。
Du Fan strongly condemned Zheng Qingzhi’s betrayal of the country, believing him to be even more greedy and treacherous than Shi Miyuan had been. Zhen Dexiu maintained, however, that the blame lay with Shi Miyuan’s original usurpation of power. He compared the situation to a skilled physician who is unjustly blamed for the mistakes of a quack predecessor. Zhen Dexiu’s differing view on this issue can be seen here.