漢代今、古學的實質性分歧，在近代學者廖平的《今古學考》中被歸納為禮制的問題，即今學主先王禮，古學主周禮。廖氏並以〈王制〉、《周禮》分別為今、古學之總綱。這一認識是建立在廖氏研究許慎《五經異義》，以及《穀梁傳》與《禮記‧王制》相闡發的基礎上，並對後世經學産生了深遠影響。不過，廖平以《穀梁》為《春秋》別傳、素王改制之書，以及有關〈王制〉的論述卻包含了諸多邏輯問題，其主要原因是不以何休《公羊》禮作為今學禮的代表。本文通過《今古學考》、許慎《五經異義》及何休《公羊》禮的相互比照，一方面認為廖平以禮制分今、古，深具創見，另一方面也認為，今、古學的禮制之分，不僅如其所言，今學主先王禮，古學主周禮，而且，今學也主周禮，今、古學在周禮觀的歧異是不容忽視的現象。文章進一步以《公羊》禮為基礎對許慎的《五經異義》重作分析，以表明區分今、古學應以何休《公羊》禮為據。並進而認為，探討漢代今、古學家的先王禮和周禮觀，對於理解漢代今、古學的實質性分歧，將開闢新的途徑。

In Jin Gu Xue Kao 今古學考, modern scholar Liao Ping views the essential difference between the New Text and the Old Text of the Han Dynasty as a question of ritual system: the New Text emphasizes the ritual system of the ancient sage sovereigns, while the Old Text emphasizes the Rites of Zhou. In addition, Liao uses Wangzhi 王制 and Zhouli 周禮 as the general principle for the New and Old Texts respectively. This understanding is based on Liao’s research of Xu Shen’s explication of Differences between the Five Classics 五經異義, Guliangzhuan 穀梁傳, and Wangzhi, and has greatly influenced the study of Confucian classics of later generations. However, Liao Ping’s view of Guliangzhuan as unofficial commentaries of Chunqiu 春秋, the book on Confucian reforms, and theories about Wangzhi contain various logical problems, the main reason being that He Xiu’s Gongyang 公羊 rites are not viewed as representative of the New Text ritual rites. This paper compares Jin Gu Xue Kao, Xu Shen’s Differences between the Five Classics and He Xiu’s Gongyang rites. On one hand, the author believes that Liao Ping’s use of ritual forms to distinguish between the Old and New Texts is profoundly original. On the other hand, the author also believes that the distinction between the ritual forms of the Old and New Texts is not merely that the New Text emphasizes the rites of the ancient sovereigns while the Old Text emphasizes the Rites of Zhou: the New Text also emphasizes the Rites of Zhou. The distinction between the Old and New Texts concerning their views on the Rites of Zhou is a phenomenon which must not be overlooked. Furthermore, using the Gongyang rites as a foundation, this article re-analyzes Xu Shen’s Differences between the Five Classics, clearly indicating that the Old and New Text studies should use He Xiu’s Gongyang rites as textual evidence. Finally, this article explores how the Old and New Text scholars of the Han Dynasty viewed the ritual system of the ancient sage sovereigns and the Rites of Zhou. This approach opens a new path for understanding the essential differences between the Old and New Text studies of the Han Dynasty.