The magic number of people needed to create social change

Your voice is louder, and more meaningful, than you think. This new research visualizes its impact.

[Source Image: Photobank/Shutterstock]

This is not the prettiest data visualization of the year–not remotely–but it may be the most important. A new study published in Science has quantified the number of people who need to take a stand before they can affect societal change on important topics like sexual harassment and human rights.


And that number? It’s a mere 25% of any group. Only 25% of people need to adopt a new social norm to create an inflection point where everyone in the group follows.

You don’t need to read the full paper to get the gist of the research, thanks to this video explainer put out by the University of Pennsylvania, which ran the study. As you can see visualized in simple cartoons, the researchers created a series of small online communities of 20 people and actually paid them to agree on a social norm (in this case, it was the name of a person in a picture). Once each group was in agreement, they paid a select few people in those groups to push for change. This group varied in size, but trial after trial, if 25% of people pushed for a new label, it was adopted, quickly, en masse.

Here’s the crazier part: The social pressure to change was so great that even though the remaining 75% of members were paid double and triple the amount of money to stick with old conventions they gave into the “network dynamics” (aka peer pressure).

In the era of #MeToo, #BlackLivesMatter, and other movements organized through grassroots groups on social media, the research adds fascinating insight into the social dynamics of protest. And in one sense, it’s an encouraging thought–that some people may be closer to changing their minds than you think. “When a community is close to a tipping point to cause large-scale social change, there’s no way they would know this,” says lead author Damon Centola, who is associate professor at the University of Pennsylvania, in a release. “And if they’re just below a tipping point, their efforts will fail. But, remarkably, just by adding one more person, and getting above the 25% tipping point, their efforts can have rapid success in changing the entire population’s opinion.”

In other words, sharing that story with a personal take on Facebook, Twitter, or real life may be more worth it than you think. Because social pressure is, in fact, measurably meaningful. And you might be the one person who stands between business as usual and real change for our world.

About the author

Mark Wilson is a senior writer at Fast Company. He started, a simple way to give back every day