歷來學者根據有限文獻，對於漢代經學發展之描述，堪謂完備。然在兩漢經說文獻多半亡佚的情況下，如欲建立漢儒之經說體系，除董仲舒、京房、戴德與戴聖外，其餘儒生幾不可得。故論述多聚焦於博士家法增立，或是官員之儒生背景。漢代崇經重儒，雖始乎武帝。不過武帝只視儒術為文飾帝國氣象的儀節而已，未必真以儒學治國。而宣帝自云漢家制度乃王霸雜用，非議時為太子之元帝純用儒術之舉，顯然表現出漢代帝王之治術立場，並不完全接受儒學。綜觀西漢經學議政之命題：前論五德歸屬、次辯鹽鐵義利，後議宗廟制度。其中讓各經學者一致大倡議論者，實為後世學者所鄙夷之災異說。因此，災異說可謂西漢純粹經學爭議之外，一個另類的學術戰場。尤其在元帝以後，西漢各個經學流派所衍生的災異說，幾已完備。正顯示經學與災異說之昌熾。如再詳加考察，更可發現西漢經學重要之轉捩點，泰半與災異說有密切關係。是以即便後人對災異說牽附荒誕，甚不苟同；亦不當漠視此一獨特之現象。否則對於西漢經學發展之論述，就恐有誤解，甚至失實。作者基於以往對春秋公羊災異說、洪範五行傳說、京氏易學說的研究心得，以西漢宣、元、成三朝為討論核心。希望透過帝王對災異之態度、學者對災異詮釋的爭議，以及災異理論之建立，做為西漢經學史的側面觀察與再詮釋

Many scholars study the development of Confucian classics studies in the Han dynasty. Because most of related texts were lost, the system of Han Confucian classics studies can only be seen with records of Dong Zhong-Shu, Jing Fang, Dai De, and Dai Sheng. Thus most discussions of the development focus on the appearance of theory schools and the intellectual background of the officials in the Han dynasty. In fact, Confucianism was not really used politically in the Han until Emperor Yuan. The political issues that Han scholars discussed were the Five Elements, salt and iron monopoly, national sacrificial system, and especially the anomalies theories. Therefore, anomalies theories have to be considered to correctly understand the development of Former Han Confucian classics studies. Based on the author's previous studies of anomalies theories, this article reinterprets Former Han classics studies with the attitudes of Emperors Xian, Yuan, and Cheng toward anomalies and other scholars' interpretations and disputes about them