Stylistic Changes of Academic Discourse in Chinese Foreign Linguistics: A Diachronic Analysis of Thematic Evolution, Syntactic Complexification, and Evaluative Positivization in CSSCI-Listed Journal Abstracts (2004–2023)

Academic discourse is evolving rapidly under the dual pressures of global scientization and local academic capitalism, yet how these systemic forces reshape the stylistic norms of non-Anglophone communities remains underexplored. To address this gap, this study investigates the diachronic evolution of Chinese Foreign Linguistics (CFL) discourse over two decades based on a corpus of 13,658 abstracts from CSSCI-listed journals (2004–2023). We employ a multi-dimensional analysis combining topic modeling, dependency parsing, and sentiment analysis to map the trajectories of research themes, syntactic structures, and evaluative stance. The results reveal a discipline in profound transformation, characterized by three distinct trends: (a) an “Empirical Turn” in thematic foci, transitioning from introspective inquiry to data-driven science; (b) a “Syntactic Rationalization,” evidenced by a universal increase in syntactic complexity to accommodate higher informational density; and (c) an “Evaluative Marketization,” where a general rise in positive sentiment masks a “Promotional Paradox”—applied fields embrace promotional rhetoric to demonstrate relevance, while theoretical core fields retreat into neutrality to signal epistemic integrity. Interpreted through the dual theoretical lenses of Communities of Practice and Activity Theory, these shifts represent a collective renegotiation of the discipline’s joint enterprise toward scientization, while simultaneously creating a stratified activity system. We argue that rhetorical style in this field has evolved into a means of distinction: while elite scholars maintain a stance of confident simplicity, emerging scholars are compelled to adopt complex syntax and promotional evaluation as symbolic passwords to navigate the competitive publication system. These findings highlight the inherent tension between scientific rigor and market visibility in the modern academic ecosystem.