The Historian’s Fingerprint: A Computational Stylometric Study of the Zuo Commentary and Discourses of the States

AbstractPrevious studies suggest that authorship can be inferred through stylistic features like func-tion word usage and grammatical patterns, yet such analyses remain limited for Old Chinese texts with disputed authorship. Computational methods enable a more nuanced exploration of these texts. This study applies stylometric anal-ysis to examine the authorship controversy be-tween the Zuo Commentary and the Discourses of the States. Using PoS 4-grams, Kullback-Leibler divergence, and multidimensional scal-ing (MDS), we systematically compare their stylistic profiles. Results show that the Zuo Commentary exhibits high internal consistency, especially in the later eight Dukes chapters, supporting its integration by a single scholarly tradition. In contrast, the Discourses of the States displays greater stylistic diversity, align-ing with the multiple-source compilation the-ory. Further analysis reveals partial stylistic similarities among the Lu, Jin, and Chu-related chapters, suggesting shared influences. These findings provide quantitative support for Tong Shuye’s arguments and extend statistical vali-dation of Bernhard Karlgren’s assertion on the textual unity of the Zuo Commentary.