A massive new study indicates that people with higher cognitive abilities are more likely to engage in behaviors that benefit society. The research links higher intelligence scores to higher rates of voting, charitable giving, and purchasing environmentally friendly vehicles. The findings offer a rare real-world look at how general mental capacity relates to cooperative actions. The study was published in the journal The Economic Journal.
Human beings are exceptionally cooperative animals. We routinely share resources with strangers and contribute to public goods. A public good is a shared resource that benefits everyone, even those who do not help pay for or maintain it. Finding a rational explanation for human cooperation has long puzzled evolutionary biologists.
Some prior academic theories suggested that generous actions might just be optimization errors. Under this idea, people act generously because they miscalculate the personal costs of their actions. Other theorists proposed that higher intelligence gives people a better capacity for ethical reasoning. A well-developed brain might allow a person to better understand the perspectives of other people.
If the ethical reasoning theory holds true, a higher cognitive capacity would naturally lead to stronger altruistic principles. People would want to act in ways that match their inner moral compass. Going against those principles could create mental discomfort. This psychological discomfort is known as cognitive dissonance.
Mikael Elinder and Oscar Erixson, economists at Uppsala University in Sweden, wanted to investigate whether intelligence directly predicts prosocial behavior. Prosocial behavior encompasses any action intended to help other people or society as a whole. Past research on this topic often relied on self-reported surveys or small laboratory games.
These traditional research methods have known limitations. People sometimes exaggerate their good deeds in surveys to look better in the eyes of researchers. In laboratory settings, the artificial nature of a game might not reflect how a person acts with their own money. To avoid these issues, the economists turned toward objective national government records.
The researchers analyzed a massive sample of 1.2 million individuals using Swedish administrative registers. Most of the subjects were men born between 1951 and 1979. These men underwent mandatory psychological and cognitive testing during military enlistment in their late teens. The researchers also looked at a large sample of about 3,000 women who voluntarily enlisted.
The military cognitive tests measured logical, verbal, spatial, and technical abilities. These scores are highly predictive of an individual’s intellectual capability throughout adulthood. The economists then linked these historical test scores to three objective measures of adult behavior. Validated government databases tracked the subjects decades after their original enlistment.
The researchers defined charitable giving using national tax agency records. During the specific study period, the Swedish government offered tax reductions for donations to approved humanitarian charities. The tax agency automatically recorded any gifts over a certain monetary threshold. This automatic recording eliminated the need for donors to actively file complex tax paperwork.
To track civic engagement, the researchers looked at validated voter turnout records from a European Parliament election. Voting takes time and effort, but an individual vote rarely decides an election. Political scientists often view modern voting as a civic duty that strengthens democratic institutions. Finally, the researchers checked national vehicle registries to see who owned cars powered by alternative fuels like electricity or ethanol.
The researchers found a strong positive association between cognitive test scores and all three behaviors. For men, a one standard deviation increase in cognitive ability was linked to a 40 percent increase in the likelihood of making a charitable donation. The same increase in cognitive ability was associated with a 31 percent higher chance of voting. It was also linked to a 14 percent higher chance of owning an eco-friendly car.
The female enlistees showed very similar patterns. Higher test scores predicted a robust swell in charitable giving and voting. The only difference was that the female data yielded results for eco-friendly car ownership that were not statistically significant.
The researchers found that scores on the logical and verbal portions of the military tests were the strongest predictors of generous behavior. Psychologists consider these specific sections to be the best proxies for general intelligence. General intelligence represents the overarching ability to reason, solve problems, and adapt to new situations.
Finding a statistical link between intellect and good deeds does not establish a direct cause. Intelligent individuals often grow up in wealthier households or better neighborhoods. These environments could independently foster prosocial habits. Parents might pass down an expectation of charity, or orderly neighborhoods might simply provide better conditions for a developing brain.
To account for these overlapping background factors, the researchers isolated a large group of 5,786 pairs of male twins within their data. Twins generally share the same upbringing, schools, and genetic background. Comparing one twin to another allows researchers to filter out the influence of shared family environments.
When the researchers compared twins, the mathematical estimates dropped but remained positive. A twin who scored higher on the cognitive tests was consistently more likely to vote and donate to charity than his brother. The relationship with owning an eco-friendly car also remained positive, though the difference between the siblings was not statistically significant.
This specific comparison suggests that unmeasured childhood environments explain about half of the initial association. Even so, subtracting those background influences left a robust mathematical relationship intact. The researchers interpret this as evidence of a genuine, direct link between intelligence and cooperative actions.
Elinder and Erixson also investigated whether other adult life outcomes explained the connection. They adjusted their statistical models for income, education level, marital status, and municipality of residence. Higher education partially explained why smarter people acted more generously. Schools often teach civic duties and explicitly expose students to broader societal issues.
Surprisingly, a person’s adult income did not explain the relationship. One might normally assume that smarter people earn more money, making it easier for them to afford charitable gifts or expensive vehicle purchases. The data did not support this specific idea. The link between intelligence and prosocial acts stood strong regardless of an individual’s personal wealth.
To verify their administrative findings, the economists also studied a smaller subset of enlistees who answered modern surveys. They found that individuals with higher cognitive scores explicitly described themselves as more altruistic. Altruism is the unselfish desire to help others without expecting a reward.
The researchers note a few caveats regarding their conclusions. The study primarily focused on monetary donations, voting, and car purchases. These distinct actions do not encompass every type of goodwill. Less intelligent individuals might simply express cooperative tendencies in other unmeasured ways, such as local community volunteering or manually helping neighbors.
Future research should explore exactly how related mental traits like empathy interact with general intellect. Understanding these mental mechanisms could help policymakers design better public awareness campaigns. If cognitive capacity dictates how people approach public dilemmas like climate change, governments might have to tailor interventions to different segments of the population. Environmental campaigns might eventually need to lean on simple behavioral incentives rather than relying solely on abstract moral arguments.
The study, “An Inquiry Into the Relationship Between Intelligence and Prosocial Behaviour: Evidence From Swedish Population Registers,” was authored by Mikael Elinder and Oscar Erixson.