BY THE OPTIMIST DAILY EDITORIAL TEAM
In a standardized behavioral experiment run with more than 100,000 people across 125 countries, 69 percent of participants chose to cooperate with an anonymous stranger on behalf of a shared goal, even when doing so meant taking a personal financial loss. Those same participants, when asked how many of their fellow citizens would make the same choice, guessed 47 percent.
The research, led by a German team and published in Science, is the first globally representative study of human cooperation. Participants were drawn from 125 nationally representative country samples.
What the experiment measured
Each participant was paired with an anonymous person from their own country and given a choice. The non-cooperative option guaranteed $100. The cooperative option paid only $70, but if both parties independently chose it, $400 would be donated toward climate action. Choosing cooperation meant accepting a $30 personal loss in exchange for a $400 contribution to a common cause, contingent on a stranger making the same call without knowing the other had.
On average, 69 percent of participants cooperated. That figure held consistently across the full range of countries in the sample.
The gap between what people do and what they expect
The same participants were asked to estimate what share of their fellow citizens would cooperate. The average guess was 47 percent. That 22-point gap between actual behavior and expected behavior appeared in 124 of 125 countries surveyed, making it nearly universal.
Lead author Armin Falk at the University of Bonn put the implication directly: “If we were less pessimistic and therefore more realistic, we could live in a better world.” The researchers describe the gap as a form of cognitive self-deception, a tendency to assess others too negatively while behaving more generously than expected. “And in doing so, we weaken ourselves.”
Why this matters beyond the laboratory
Collective action on problems that require coordination, from climate change to public health, depends in part on what people believe others will do. If most people assume most others will not participate, the incentive to participate weakens. The pessimism becomes self-fulfilling.
The researchers frame cooperation as a basic prerequisite for social well-being. Many challenges can only be overcome if people contribute to the common good beyond their immediate interests. The data suggests most people already do. They just do not know that most other people are doing the same.
Source study: Science— Homo cooperans: Understanding the nature of human cooperation
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