+- Scivillage.com Casual Discussion Science Forum (https://www.scivillage.com)
+-- Forum: Science (https://www.scivillage.com/forum-61.html)
+--- Forum: Chemistry, Physics & Mathematics (https://www.scivillage.com/forum-77.html)
+--- Thread: Research New study finds a simple rule behind how social norms spread (society as math) (/thread-20263.html)
New study finds a simple rule behind how social norms spread (society as math) - C C - Apr 23, 2026
https://www.eurekalert.org/news-releases/1125579
INTRO: A paper in Proceedings of the National Academy of Sciences (PNAS) offers a strikingly simple answer to a longstanding question: How do people learn and settle on shared social conventions, from everyday habits to workplace norms?
Researchers from the CUNY Graduate Center, the University of Pennsylvania, and Stanford University found that people do not primarily learn by copying others or by calculating the most likely choice. Instead, they follow a two-stage process — sampling behaviors at first, then committing once enough evidence accumulates.
The study shows that this shift is governed by a simple mathematical rule known as the Tolerance Principle, which predicts when people have seen enough regularity to treat a pattern as a rule despite some exceptions. Originally developed to explain how children learn the grammar of their native language, the researchers found, it also predicts how adults adopt shared behaviors — and even how competing norms can overturn one another.
“People often assume that social learning is about imitation or careful optimization,” said Spencer Caplan, Linguistics professor at the CUNY Graduate Center and co-lead author of the study. “What we found is something more basic and more human: People explore different options, but once a pattern crosses the threshold of ‘good enough,’ they commit to it — and stick with it even when there’s some conflicting evidence.” (MORE - no ads)