顧頡剛發表於民國十九年的〈五德終始說下的政治和歷史〉，奠定了其日後在「漢代學術史」上的崇高地位。在該文中，顧頡剛詳細地分析漢莽之際的劉歆如何利用「終始五德」改造古史系統，因此學者們多以為此論點為顧頡剛先生獨創的見解，忽略了其曾自言〈五德終始說下的政治和歷史〉一文的形成，其實是受到崔適《史記探源》中關於「終始五德」論述的啟發。而本文即依循著顧頡剛對崔適《史記探源》推闡的脈絡，分析崔適「終始五德」學說的要點，以及論述顧頡剛在〈五德終始說下的政治和歷史〉該文中對崔適學說的「修正」，從而發現〈五德終始說下的政治和歷史〉除了闡述劉歆與「終始五德」之關係，尚有一隱含的要義，即：顧頡剛旨在論證「劉歆佐莽篡漢」。

Cui Shi was a famous classical scholar and historian in modern china. In his opinion, "Five Elements" was falsified by Liu Xin for supporting Wang Mang to usurp han dynasty. Therefore, the records of "Five Elements" are fake in Shi Ji and Han Shu. Gu Jiegang, Cui Shi's student, considered there are some points in Cui Shi's study that are worthy of discussion. In Gu Jiegang's opinion, "Five Elements" that recorded in the history was believable. Liu Xin just use the popularity of "Five Elements" for supporting Wang Mang to usurp han dynasty.