Metaphors matter: The effect of biological dehumanizing language on indirect aggression

Biologization – a form of dehumanization in which others are considered as disease carriers rather than humans – is common in the political debate; however, its effects have been understudied. To fill this gap, we conducted three pre-registered experimental studies in which biological language was manipulated through vignettes. We found that using disease metaphors (vs. negative but non-dehumanizing language) to describe others increased biologization, indirect (vs. direct) aggression, and exclusionary intentions. Study 1 (N = 201) provided initial evidence of these associations. Study 2 (N = 204) and Study 3 (N = 248) deepened these results, indicating that the effect of biological language on indirect aggression via biologization (Study 2) and accessibility of aggressive thoughts (Study 3) was bigger and significant for participants with high and medium (vs. low) levels of disgust sensitivity. This research highlights how framing groups as biological threats can intensify aggression and exclusion, shedding light on this dehumanizing rhetoric.