The Science of Tipping Points: How 25% Can Create a Majority

Do you have to wait for more than 50% of the group to agree with a minority opinion before it can take over? It turns out, you need far less than that.

Sabrina Stierwalt, PhD
5-minute read
Episode #307

Around 100 years ago, women were legally banned from wearing pants. In fact, women were not allowed to wear pants on the floor of the United States Senate until 1993. In the 17th century, men commonly wore high heels. In the '80s and '90s, you could expect to be greeted with a thick cloud of cigarette smoke when you entered public spaces, like restaurants and even offices. As a child, I rarely rode in a car seat and always slept on my stomach in a crib surrounded by soft, padded bumpers—all things that would get a parent ostracized if not arrested today.

As much as we feel bound by them, our societal norms are usually fluid.

Less than 10 years ago, marriage was not a privilege extended to everyone—and now we have viral videos of two grooms doing incredibly impressive lifts and mashup dances for their first dance. I can now get a care package of cookies delivered to my friend who just had surgery at her door in less than 48 hours and they’ll look better than any that I could make myself anyway. Public opinion is even turning on climate change. In the United States, the majority believes not only that global warming is real but that we should be doing more to combat it.

As much as we feel bound by them, our societal norms are usually fluid. Sometimes that fluidity comes about because of advances in our knowledge about safety or public health or the irrefutable science behind a warming atmosphere. Sometimes our societal norms are adapting to new technologies. And sometimes we see changes in public perspective because we begin to allow ourselves to accept change and the associated risk.

But where does that tipping point happen? When does a minority opinion begin to become the majority? It turns out that you don’t have to wait for 50% of the group to be on board with an idea for that idea to have any hope of becoming the majority opinion.

From minority to majority—a tipping point study

In a study published in the journal Science, Dr. Damon Centola of the University of Pennsylvania and his collaborators found that the tipping point comes at only 25%. In other words, once a minority view is held by at least one quarter of the group, that minority view will take over and eventually become the majority.

The fact that this so-called tipping point comes into play far below a 50% majority is not a new discovery. In a ground-breaking study from 1977 led by Dr. Rosabeth Kanter, the treatment of women in the workplace was seen to improve only when they reached a critical population of at least 35%. Researchers have also long relied on computational models to test where minority views begin to gain traction. In a 2011 study based on models, researchers found that only 10% of the group had to hold an opinion before it caught on with the others. The Centola study then allows the ability to see the tipping point play out in a fairly large group of people within the controlled environment of their experiment.  

When at least 1/4 of the group was in favor of going against the status quo, the rest of the group began to follow.

In Centola’s study, 194 people were divided into ten groups and instructed to play an online game where they worked together to develop their own societal norms. As an example, two players would be shown a face and asked to assign a name to that face. They were rewarded with points or money if their names agreed, while the same amount of points were deducted if their names were not a match. Pretty quickly, naming conventions and norms set in that were followed by almost all of the players.

The masterminds behind the study then sent in actors who were committed to names that went against the status quo. Researchers were able to test how many of these actors were needed before they could flip popular opinion in their favor. It turned out that number was around 25% of the group. When at least 1/4 of the group was in favor of going against the status quo, the rest of the group began to follow. If the rabble rousers only made up one-tenth or even one-fifth of the group, however, their alternate opinions would not gain traction against the preset norms.

So what was happening? The study's authors suggest that most likely, the original, uncommitted players begin to encounter seemingly larger groups of otherwise committed actors (those sent in to stick to their dissenting views), and begin to flip. Once more and more flip, it no longer feels risky to join in the group attempting to change the status quo.

For example, I would love to wear my pajamas to work but I realize this is, unfortunately, socially unacceptable. However, if a few of my coworkers wore their pajamas to work and were steadfast in the opinion that it was okay to do so, I’d feel more secure in not being the only one, and I would be more likely to join them. (Ahem, I hope some of my coworkers are listening. Let’s make this happen!)

There are two important caveats to note, however, when thinking about the results of this study in the context of the political issues that divide our societies today. First, the players in this study were just that—players. It is very reasonable to expect that you can more easily convince someone playing a game to change their opinion on an arbitrarily-assigned name than, say, convincing your uncle to change his mind on universal healthcare.

Centola and his colleagues attempted to address this potential bias by providing incentives for community members in virtual communities they created via models to not change their minds. In that case, it does become harder to shift public opinion, but only by a little bit. The models predict that a higher minority percentage of 30% is needed for a tipping point, which, while higher than 25%, is still intriguingly far below a majority at just above 50%.

The second important difference between the study and reality is that all participants in the study approach the decisions with the same amount of power. There is no established hierarchy of race, gender, sex, wealth, etc., that lends more sway behind some opinions over others as there is in real life.

How does minority opinion become majority?

The results of these tipping point studies remind me of one of my favorite TED talks called How to Start a Movement by Derek Sivers. If you want to check it out, the whole talk is only three minutes long. In the talk, he shows footage of a lone dancer at an outdoor concert, flailing away as everyone else around him remains seated. He is alone in this pursuit for quite a while until finally one other person joins him. Soon after the second dancer has joined, others follow, until the majority of concert-goers are on their feet and moving their bodies to the rhythm.

As Sivers points out, sure, the first dancer had to be brave and had to choose an action that wasn’t hard for potential followers to do, but until the second dancer joins him, he’s just a lone weirdo. The second dancer is really the one who starts a movement because now the risk is lowered for others to join, as they soon do.

So next time you see a lone weirdo doing something that looks like fun or doesn’t actually seem that weird to you, consider joining them. You may just be the person that tips the minority scale from 24% to 25%.

Image from Shutterstock (Bigone). 

Citations +
Please note that archive episodes of this podcast may include references to Ask Science. Rights of Albert Einstein are used with permission of The Hebrew University of Jerusalem. Represented exclusively by Greenlight.

About the Author

Sabrina Stierwalt, PhD

Dr Sabrina Stierwalt earned a Ph.D. in Astronomy & Astrophysics from Cornell University and is now a Professor of Physics at Occidental College.