Psychologists reveal our "blatant dehumanisation" of minority groups

Participants used a sliding scale under an image like this
to indicate “how evolved” they believed an average
member of various racial and ethnic groups to be

Ghanaian footballer Emmanuel Frimpong’s match in Russia last Friday ended nastily: “When the match was stopped,” he said, “the fans started shouting ‘monkey’ at me.” Redefining human beings as animals in this way, or as vermin, or insects, is no small thing; time and again it’s augured the worst that our species has to offer.

In the wake of the Holocaust, early researchers sought to understand blatant dehumanisation, such as people’s greater willingness to apply an electric shock to subjects who were depicted as inhuman. More recently, researchers have turned to studying “infrahumanisation”: a more subtle variant where certain groups are assumed to be less prone to embarrassment, compassion or other more sophisticated human emotions. But blatant dehumanisation is still with us, and a new paper suggests that by measuring it we can better predict people’s intentions (especially when they’re feeling threatened) towards degraded minority groups.

Across several online surveys, hundreds of US and British participants were asked a host of attitudinal questions and asked to rate different ethnic groups on how evolved they were, using a graphic depicting the famous “Ascent of Man” (see picture). By setting a slider somewhere between the two ends, participants were free to consign ethnic groups to being less than human.

Initial results found US citizens dehumanise Arabs and Muslims the most, so the paper focuses on these groups, although a similar, weaker pattern of results was also for the other groups, such as South Korean or Mexican people.

Where the US participants placed the Arabs on the Ascent scale turned out to be revealing of their wider attitudes: it correlated with their desire for reducing Arab immigration, lack of sympathy towards an unjustly treated delinquent teen of Arab ethnicity, and endorsement of acts of violence, such as advocating torture or bombing an entire Arab country (this was true even after controlling for measures of infrahumanisation).

The scale seems particularly useful when the in-group feels under direct threat of violence. In the two weeks following the Boston Marathon bombing, US participants showed significantly higher Arabic dehumanisation on the Ascent scale than in data collected two months before. This was again a strong predictor of many of the measures described above and of eliminativist attitudes such as agreeing with a tweet that all Muslims should be wiped off the face of the earth. A similar result was obtained with a British sample following the murder by Islamic converts of the off-duty British soldier Lee Rigby: dehumanisation of Muslims was high, and this time correlated with support for drone strikes, punitive treatment of the perpetrators, and aggressive counterterrorism policy against Arabs and Muslims.

In this paper’s initial surveys, the measures of more subtle dehumanisation (infrahumanisation) had offered some explanatory value, sometimes overlapping with the Ascent scale results, sometimes complementing them. This was much less so in these last two post-crisis situations. Pre versus post Boston Marathon, the participants’ subtle dehumanisation scores didn’t budge, failing to reflect the overt changes in attitudes evinced by the participants (on immigration etc), or the hostile advocacy of the US-Boston participants and the UK-Rigby participants.

This is not to say that measures of infrahumanisation are redundant – they capture a different aspect of “Othering”, one that could occur in low-stakes, everyday interactions. But this more subtle dehumanisation appears to shift more slowly – perhaps through the drip-drip of culture – whereas blatant dehumanisation, as measured by the Ascent scale, seems to better capture our states of mind in volatile contexts. In an age where nationalism and ethnic identity are returning to the political centre stage – from the rise of the European far-right to the emergence of the so-called Islamic State which treats those unlike themselves as non-human – it’s important that we are able to measure and understand this treatment of “the other.”


Kteily, N., Bruneau, E., Waytz, A., & Cotterill, S. (2015). The Ascent of Man: Theoretical and Empirical Evidence for Blatant Dehumanization. Journal of Personality and Social Psychology DOI: 10.1037/pspp0000048

further reading
Seeing others as less than human
Robot prejudice
The psychology of violent extremism digested
Committed nurses cope with stress by dehumanising themselves and their patients

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

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