《资治通鉴》作为不朽的史学巨著，对宋代以降的史学产生了广泛、深远的影响。既有研究主要局限于历史编纂学层面，且研究理路不乏值得反思之处，有必要从新的视角加以检讨、考察。其中知识史的研究范式能够提供有益的借鉴。

《通鉴》历来被奉为不可不读的经典，但又素以难读著称，于是不断有学者尝试改编《通鉴》，以便阅读。自隋唐以降，类书的范围不断扩展，编纂手法日益丰富，应用逐渐广泛。宋人读书治学，应付科考，普遍借助类编之法。在这种历史背景下，袁枢苦《通鉴》浩博，欲加以改编，便自然而然地取法类书。同时又稍变其分类标准，创造性地将同属一个事件的诸条归并为一类，使一事即为类书之一类，一类即如著述之一篇，从而无意间开创了纪事本末体。

编年体既有难读的一面，也有易读的一面，纪事愈简则愈彰显易读的一面，愈详则愈彰显难读的一面。《通鉴》之所以难读，主要原因是内容浩博、篇帙宏富，若欲避难趋易、化繁为简，删繁节要自然就是行之有效的办法。通过摘录节要的方法辅助阅读内容浩繁的编年史，唐人已付诸实践。《通鉴》问世后，亦不断有学者用此法阅读是书，其中朱熹提倡尤力，条例也最为严谨。按照朱熹的方法，在读《通鉴》的过程中会形成一略一详两种节本，两者分别近似司马光《通鉴目录》和《通鉴举要历》。朱熹将两种节本融为一体，并加以整齐，从而形成了《资治通鉴纲目》，纲目体亦由是生成。

不过，真正坚持阅读《通鉴》原书并自行节要的只是极少数读者，更多读者则利用他人所编节本。南宋以后，一系列名目纷繁的《通鉴》节本大量刊印，广泛传播，经久盛行。初学者视之为读《通鉴》进阶，科考士子则赖其简便易读而有益后场，元明两朝官方也加以推广。在相当普遍的阅读实践中，《通鉴》节本完全替代了原书应有的位置，历代大部分读者所阅读、使用、理解的《通鉴》，实乃《通鉴》节本。

《通鉴》节本在删削原书之余，亦因应读者需求，不断增补附益，其内容和功用很快超出原书之外，衍生出“简明编年史”的著述体系。这类史书传播极为广泛，对明代历史演义小说的兴起和发展，对明清时期历史知识的普及，对近世读书人知识世界的塑造，皆影响至深。

以知识史的视阈考察《通鉴》对中国近古史学的影响，提醒我们在学术史的讨论中，要从古人读书治学的日常出发，注意回归具体的历史情境，落实具体的历史联系。在探讨经典的流传和影响时，应进一步扩大视野，不能将目光局限于经典本身。

The immortal masterpiece Zizhi Tongjian has exerted extensive and profound influence on the study of historiography since the Song dynasty. Previous research has mainly focused on the aspect of historical compilation, in which the history of knowledge can provide beneficial insights, but mostly the methodology and perspectives employed are worth reevaluating.

The Tongjian has always been regarded as a must-read classic, but it is also known for its difficulty. For easier reading, scholars have continuously attempted to adapt and simplify it. Since the Sui and Tang dynasties, the scope of reference books (leishu) has expanded, and their compilation techniques have become more sophisticated and widely applied. During the Song dynasty, scholars commonly used reference books to aid their study and preparation for examinations. Yuan Shu drew inspiration from reference books when facing the monumental task of the Tongjian, and modified the classification criteria, creatively consolidating multiple entries related to the same event into a single category, making each event a category within the reference book and each category resembling a chapter in a written work. Inadvertently, he pioneered the genre of chronological records.

The chronological style has both easy and difficult aspects. The more concise the record, the easier it is to read, while the more detailed it is, the more challenging it becomes. The main reason for the difficulty of reading the Tongjian lies in its extensive content and voluminous texts. To make it more accessible and concise, condensing and summarizing the essential parts has been an effective approach. The method of excerpting essential passages to facilitate the reading of extensive chronological records was already practiced during the Tang dynasty. After the publication of the Tongjian, scholars continuously used this method to read the book, with Zhu Xi being a prominent advocate and his regulations being the most rigorous. Following Zhu Xi’s method, the process of reading the Tongjian would result in the creation of two types of abridged versions: one resembling Sima Guang’s Tongjian Catalog and the other resembling Sima Guang’s Tongjian Juyao. Zhu Xi merged these two abridged versions into a single work and organized them systematically, thus forming the Zizhi Tongjian Gangmu, which also follows the format of reference books.

However, only a small number of readers truly insist on reading the original Tongjian and summarizing it themselves, while most readers rely on the abridged versions compiled by others. Since the Southern Song dynasty, numerous editions of abridged versions of the Tongjian were printed and widely circulated, becoming popular reading materials. Beginners considered these editions as a stepping stone to reading the Tongjian, and scholars preparing for examinations found them convenient and beneficial. The official authorities during the Yuan and Ming dynasties also promoted their usage. In the widespread practice of reading, the abridged versions completely replaced the original book in the position of being read, used, and understood by the majority of readers throughout history. Therefore, the abridged versions became the de facto Tongjian for most readers.

In addition to omitting content from the original book, the abridged versions also expanded and supplemented certain aspects according to readers’ needs. Their content and functions soon surpassed that of the original book, giving rise to a genre of “concise chronological history.” Such historical books spread widely and had a profound impact on the rise and development of historical fiction in the Ming dynasty, the popularization of historical knowledge in the Ming and Qing dynasties, and the shaping of the intellectual world of modern readers.

Examining the influence of the Tongjian on ancient Chinese historiography through the lens of the history of knowledge reminds us that in discussions of academic history, we should start from the daily practices of ancient scholars in reading and studying, pay attention to concrete historical contexts, and establish specific historical connections. When exploring the transmission and influence of classics, we should broaden our perspectives and not limit our focus solely to the classics themselves.