How Disgust Becomes Law

Patrick, Carlton and Lieberman, Debra, How Disgust Becomes Law (August 24, 2017). Forthcoming in The Moral Psychology of Disgust, Nina Strohminger & Victor Kumar (Eds.), London: Rowman & Littlefield, 2018. https://ssrn.com/abstract=3025885

Abstract: This chapter provides a psychological examination of the many ways in which disgust permeates the law. Using an evolutionary lens, the chapter explores the various adaptive functions of disgust, and shows how those functions can be co-opted by psychological systems designed to generate and enforce moral norms. In doing so, the chapter also provides an explanation for why and how many of the behaviors we view as "disgusting" tend to become behaviors we label "wrong."

Keywords: evolutionary analysis in law, legal theory, disgust and the law, law and psychology, behavioral biology, morality, evolutionary psychology

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A second way that disgust is used by systems sensitive to alliance formation and group condemnation relates to communication. When individuals broadcast signals of disgust, they provide a means to infer the likelihood of alliance formation in the service of condemning a particular behavior. Personal disgust, when echoed by another person and then another person and then another, is a cue of mental alliance that can facilitate the formation of a coalition targeting particular individuals engaging in the disgust eliciting act. Disgust is not unique in this respect. Hearing the terms “I hate people who tailgate on the highway” can rally the troops as well. President Trump (and he is hardly the first) has continually attempted to incite fear and anger in an attempt to marginalize Mexicans seeking to immigrate to the US. These kinds of phrases give an indication of others’ willingness to form an alliance condemning others. In this way, disgust language and facial expressions can either be or not be actual felt disgust. One can personally feel disgust and communicate this, or one can merely use the language of disgust.