Epistemic and Deontic Modality: A Linguistic Indicator of Disciplinary Variation in Academic English

We present a pragmatic analytical framework to explore the reasons underlying the differences in the use of modal verbs in English research articles (RAs) in three different academic disciplines: medicine, biology and literary criticism. Sentences may be either modalized or unmodalized. The use of modalized statements is a key feature of academic writing, and this expression of modalization has been widely researched. However, most of this investigation has not considered the linguistic distinction of types of modalization: epistemic modality (questioning the certainty or probability of a statement) and deontic modality (laying obligations or giving permission to the reader/audience). This linguistic dichotomy may be an important tool to describe disciplinary variations in academic writing. It is hypothesized that different disciplines favor different types of modality. Results in this study indicate that scientific RAs (i.e., in medicine and biology) mostly use epistemic modality, whereas literary criticism RAs combine the use of both epistemic and deontic modality. It is our contention that the selection of one specific type of modality (i.e., epistemic or deontic) is a matter of a deliberate stylistic choice of writers influenced by the pragmatic context of their specific and distinct academic discourse communities.