By Olivia Solon, Wired UK

A new study shows that people feel morally cleansed when they are physically clean, and as such are more inclined to judge others more harshly.

The study, with the somewhat Victorian-sounding name of "A clean self can render harsh moral judgment" was led by Chen-Bo Zhong at ﻿﻿﻿the University of Toronto Rotman School of Management and appears in the Journal of Experimental Social Psychology.

Some 58 undergrads were invited to a lab filled with spotless new equipment. Half of the students were asked to clean their hands with antiseptic wipe, so as not to soil the shiny surfaces. Afterward all the students rated the morality of six societal issues – smoking, illegal drug use, pornography, profane language, littering and adultery – on an 11-point scale ranging from very moral to very immoral. Those who’d wiped their hands made far-harsher judgments than those who didn’t.

“Participants who cleansed their hands before rating the social issues judged these issues to be more morally wrong compared to those who did not cleanse their hands,” the researchers report.

In a follow-up study, hundreds of participants were told to read a short passage that began, “My hair feels clean and light. My breath is fresh. My clothes are pristine and like new,” made harsher moral judgments about 16 social issues compared to those primed to feel dirty by reading a passage that read, “My hair feels oily and heavy. My breath stinks. I feel so dirty.”

A third study was identical to the second, except that after reading either the dirty or clean passage of text, the 136 undergrad participants also ranked themselves against their peers on several factors including intelligence, attractiveness and moral character.

Those who held a self-image of cleanliness and purity made more harsh moral judgements on social issues. Crucially, this association was entirely mediated by their having an inflated sense of moral virtue compared with their peers. (By contrast, reading the clean vs. dirty text made no difference to self -rankings on the other factors).

“Acts of cleanliness have not only the potential to shift our moral pendulum to a more virtuous self, but also license harsher moral judgment of others,” Zhong and his team concluded.

Image: Flickr/Arlington County

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