Is purity a distinct and homogeneous domain in moral psychology?

Abstract

No" is our answer to the question in our title. In moral psychology, a purity violation (defined as an immoral act committed against one's own body or soul) was theorized to be a homogeneous moral domain qualitatively distinct from other moral domains. In contrast, we hypothesized heterogeneity rather than homogeneity, overlapping rather than distinct domains, and quantitative rather than qualitative differences from other hypothesized domains (specifically, autonomy, which is harm to others). Purity has been said to consist of norms violations of which elicit disgust and taint the soul. Here we empirically examined homogeneity: whether violations of body (e.g., eating putrid food) belong in the same moral domain as violations of the soul unrelated to bodily health (e.g., selling one's soul, desecrating sacred books). We examined distinctness: whether reactions to purity violations differ in predicted ways from those to violations of autonomy. In four studies (the last preregistered), American Internet users (in Studies 2 and 4, classified as politically conservative or liberal; Ns = 80, 96, 1,312, 376) were given stories about violations based on prior studies. Nonhealth purity violations were rated as relatively more disgusting, but less gross (the lay term for the reaction to putrid things) and more likely to taint the soul than were health-related ones. Surprisingly, both health and nonhealth purity violations were typically judged as only slightly immoral if at all. Autonomy violations were rated as more disgusting and tainting of the soul than were purity violations.

The puritanical moral contract: purity, cooperation, and the architecture of the moral mind

“…We introduced the notion of puritanical morality, however, because purity seemed too vague of a notion to provide a good explanatory target. Our target article converges with recent recommendations to abandon or at least reconceptualize the notion of purity in moral psychology (Crone, 2022;Gray et al, 2022;Kollareth et al, 2022). We and other commentators see three reasons to do so.…”

“…People don't cite these behaviors as typical moral violations (Gray & Keeney, 2015). And it's not even clear whether people perceive them as really immoral (Kollareth et al, 2022).…”

Moral disciplining: The cognitive and evolutionary foundations of puritanical morality

“…This constellation of moral values gained popularity in psychological and evolutionary approaches to morality as part of the so-called "Purity" moral concerns (Graham et al, 2013;Haidt, 2012Haidt, , 2007Haidt & Joseph, 2004. The Purity category, however, is a murky concept with no clear definition (Crone, 2022;Gray et al, 2022;Kollareth et al, 2022).…”

“…Autonomy violations occur when a perpetrator intentionally harms another person and thereby elicits anger in a witness, whereas purity violations occur when the perpetrator, intentionally or not, defiles his or her own body or soul and thereby elicits disgust in a witness . However, more recent research questions whether purity is distinct from autonomy Kollareth, Brownell, Durán, & Russell, 2023).…”

“…Examples include: thinking of scriptures while expelling excrement (Haidt, 2003) or cleaning a bathroom with the national flag . When studies de-confound purity violations from pathogens, those alleged purity violations are not perceived as disgusting Kollareth et al, 2023;.…”