What we know about people is WEIRDer than we think
Updated: Mar 18
Studies in psychology have discovered many things: people in social situations tend to conform to group norms; they have a propensity to be obedient to those in authority; the signalling of happiness, surprise, anger and joy, which anyone can do, can be read by others; kinship is a powerful mechanism for structuring society; individuals’ fear of parasites, spiders and snakes is widespread. Are these characteristics true for everyone?
In one of my degrees I did a major in psychology, and as a consequence I’m supposed to know something about human behaviour such as this, and what makes people everywhere tick. But I know less about people than I’d like to think – and so it seems, do most psychologists.
That’s because a famous study in 2010 has pulled away at the threads of the cloak of respectability that the discipline of psychology once proudly wore. This research said the people enrolled in psych studies were so different from everyone else that it put at risk any claim to know about human propensities as universal characteristics. In fact almost all people in such studies were WEIRD – that is to say, Western, Educated, Industrialised, Rich, and Democratic.
Few people in the past had, or even in the present world have, these characteristics. It is very true to say that through the course of the entire length of human history, dating from when Homo sapiens first evolved from Homo erectus or Homo heidelbergensis some 200,000 years ago, even though some would have been weird, almost no-one amongst all those in that long period who were born and died were WEIRD. A tiny proportion of everyone who ever lived had a Western-style education, no-one until the mid-eighteenth Century was industrialised, very few in past societies were educated, even fewer were rich and it is only in the blink of an eye, over the last hundred years, starting with the earliest experimentation in 5th Century BC ancient Greece, that any society has been remotely democratic.
Even today, reports the Pew Research Center, a non-partisan ‘fact tank’, 57% (96 of 167) countries in the world are democracies – and only 12% (20) are rated as full democracies, according to the Democracy Index of The Economist’s Intelligence Unit. So, for all these reasons the cohort of people who have been experimented on in psychology is laughably low in number, laughably proscribed historically and contemporaneously, and laughably strange in characteristics.
Yet there was more. The WEIRD study said that the vast majority of psychological experiments ever conducted – around 96% of them – were essentially on 18- or 19-year-old university students enrolled in first- or second-year undergraduate psychology classes, who were participating in the experiment to earn credit towards their degree. This, of course, is a very small sliver of the range of groups that make up society, and it forces these young participants, or at the very least provides an undue influence on them, to join in the studies. The notion of a ‘unbiased sample’ – so treasured in science – was being completely and systematically disregarded.
And these students predominately hail from a mere five countries – the United States, Canada, Britain, Australia, and New Zealand – but mostly, America. I don’t know about you but I’m not an 18- or 19-year-old undergraduate psychology student. They are becoming adults having developed through the early and mid-teens, are maturating, and their brains are re-wiring, but they are not there yet. I share some human characteristics with them, such as being bipedal, conscious, reflective and constantly thinking, and I and all those psych students are both riven with all the usual strengths and weaknesses of Homo sapiens, but I’m not much like that group, nor do I identify with it much, perhaps especially psychologically.
Yet if you read the psychology literature it almost all either implies or directly asserts that what we know from these studies is generalisable to the entire human population. This truly cannot be the case.
WEIRD people mostly live in the modern world of towns and cities, with access to technology, housing, schools, education, pubs, sporting arenas, hospitals, libraries, shopping malls, and the law. More importantly, they hold specific views on how society functions, marriage works, and who can own private property. Joseph Henrich, the leading proponent of the WEIRD hypothesis, blames a lot of this on the Catholic Church dating back to the middle ages. But such views are not held by those in kinship-based, small-scale societies, which is where humanity came from, and which many non-Western populations still favour today – and those people are not nearly so prosocial, individualistic, and rationally- and analytically-minded. Kin-based groups are less individualistic, more conforming, obedient to others in the hierarchy, supportive of the in-group, and share a greater sensitivity to relationships and the ecosystems in which they live than WEIRDos.
Just so we can see how different WEIRD people are, even in a test as seemingly universal as how people perceive two lines, such as in the Müller-Lyer Illusion, striking differences are found – and American undergraduates are most radical of all groups. Both lines at the top of the diagram are the same length, as shown by the identical red lines below.
US undergraduates need for the first line to be a fifth longer than the second before they are prepared to consider them equal. By way of sharp contrast, the San people of the African Kalahari Desert don’t even see the lines being at different lengths, so there is no illusion for them. So saying the results of this test shows a universal attribute, and that the study is generalisable to the whole of humanity, is indefensible.
Other experiments, when conducted cross-culturally, reinforce this lack of generalisability. Testing WEIRD undergraduates in the laboratory for how much money they would share with others (e.g., in the Ultimatum Game and the Dictator Game), shows they differ markedly from non-WEIRD cohorts. Undergraduate freshman would offer to a stranger 32% of an amount allocated to them to share, whereas other Americans would offer on average 47%. Other non-WEIRD groups would offer different amounts again. In other examples, WEIRD people, asked to self-rate their own performance at chess or driving, markedly view themselves terribly favourably, and rate themselves as above-average, even exceptional, on such tasks – even if they are mediocre performers. The difference can be profound: some East Asian groups, for example, rather than be self-promoting, are way, way opposite, and strongly self-effacing.
All-in-all, WEIRD people are extreme, especially Americans. Seymour Martin Lipset, a famous sociologist, as early as 1996 in his book American exceptionalism: a double-edged sword, noted how Americans, contrasted to every other group, were the most intense patriots, litigants, philanthropists, populists, optimists, and have the least class-consciousness. They also have amongst the lowest voter turnout, the highest crime rates, the longest working week, the shortest vacations, higher GDP, more inequality, greater levels of divorce, more volunteerism, and were least supportive of government as a societal solution than almost all other groups. Highly educated US college students are even stranger on many variables: more individualistic, more autonomous, more supportive of racial diversity, and less conforming than other Americans. WEIRDer than the WEIRDest, you might say.
What does this mean and what are the implications for our understanding of people? At my most belligerent, I could push an argument that we should consign to the trashcan almost the whole of the psychological literature to date and start again, with researchers who are much more willing to engage with different populations than English-speaking late teens leading privileged lives.
I could be a more generous critic than this and argue that psychologists shouldn’t jettison everything, but, with great humility, do a whole suite of replication or confirmatory experiments by enrolling other groups outside of undergraduate psychology, with the widest spread possible of races, ages, education levels and societal features.
The aim should thereby be to explore the full gamut of human experience. In what ways do humans have similar or different natures, behaviours and minds than we think people have to date based on that narrowly-constructed literature, is a key outstanding question.
Either way, psychology has work to do in its appreciation of human nature and how differently the mind works across different cultures. Put that way it’s not a negative to say that the exciting journey of the behavioural sciences in understanding that most complex of subjects, us, is not so much at a crossroads but in the foothills, with Everest in front, challenging every researcher worthy of the name psychologist to climb higher.
But there’s a residual problem: psychologists doing all those research studies are WEIRD too. For genuine understanding, that must change, also.
DeSilver, Drew (2019). Despite global concerns about democracy, more than half of countries are democratic. Pew Research Center, Fact Tank. May 14. https://www.pewresearch.org/fact-tank/2019/05/14/more-than-half-of-countries-are-democratic/
Henrich, Joseph, Heine, Steven J, Norenzayan, Ara (2010). The weirdest people in the world? Behavioral and Brain Sciences. 33(2-3):61-83.