We're not of the same feather: Disgust sensitivity and reduced perceived similarity to unknown others

Perceptions of interpersonal similarity are accompanied by attraction and bonding, often leading to physical contact. Given that physical proximity to social beings increases the odds of catching infectious diseases, we propose a reverse relationship, whereby sensitivity to the presence of pathogens results in perceiving unfamiliar others as less similar to oneself. Four studies involving 980 participants and operationalizing others in three different ways confirm that individual differences in propensity to feel disgust (i.e., react emotionally to potential sources of pathogens in the environment) are associated with perceptions of interpersonal similarity to strangers. Study 1 showed that individuals who score higher in disgust sensitivity perceive themselves as less psychologically similar to visually displayed social targets. Study 2, using vague descriptions of hypothetical figures, found that high-disgust-sensitivity participants tend to assume that others' personal preferences contrast with their own. Study 3 demonstrated that the disgust–dissimilarity association holds for prototypical members of social groups. Finally, Study 4 confirmed that this link reflects pathogen-related (above and beyond sexual or moral) disgust. In all studies, controlling for participants' gender, religiosity, and illness recency did not change the results. We discuss our findings and propose novel directions for future research.