Social Proof

The Basic Idea

Think back to the first day of classes at college. Everything is new to you as you nervously enter the lecture hall and pick a seat. Not sure whether to use your laptop or a notebook, you likely looked around to see what your peers were doing. You might have even looked at what they were wearing to know whether your attire was appropriate. Maybe you checked if people were drinking coffee or eating a snack to know if that was acceptable and acted according to the behavior of those around you.

This kind of conformity to socially acceptable behavior is known as social proof. Social proof is both a psychological and social phenomenon where we tend to copy the actions of those around us to try and conform to a behavior that we believe to fit the situation. Essentially, we are looking to those around us for clues about the ‘right’ way to behave, especially in ambiguous circumstances. At times, social proof is a stronger influence than rules – if other people are not following the guidelines, we don’t feel like we have to either. For example, if you saw that everyone was crossing a crosswalk when the light was red, you might follow their footsteps and do the same.

Lack of skepticism is often the result of our social beliefs. No one would believe such absurd nonsense as a moon made of cheese or a flying teapot when it is proposed in such an unfamiliar way. However, when we encounter equally absurd belief systems in socially or historically-familiar contexts, they seem to have a measure of proof and be established or valid. In other words, a lot of people believing some total bullshit creates a form of social proof.

– Sia Mohajer, an educational psychologist, in his book I’m Right – You’re Wrong: How to Think Clearer, Argue Better and Stop Lying to Yourself1

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Key Terms

Social norms: Collectively held beliefs on what kind of behavior is appropriate/acceptable for a given circumstance or community.

Normative conformity: conformity influenced by our desire to be liked/accepted.2 

Informational conformity: conformity influenced by our desire to be correct.2

Informational social influence: the change of behavior/action that happens when we conform to people who we believe know better 3; what occurs as a result of using social proof to guide our behavior.

Herd Behavior: behaviors of individuals in a group who act collectively without explicit, centralized direction.


One of the first series of experiments to study social proof was conducted all the way back in the 1950s by Solomon Asch, a pioneer of social psychology, especially with regards to conformity.

His first conformity experiment, which went on to be widely replicated within social psychology, was conducted in 1951. In this experiment, 50 college-age participants were told that they were going to participate in a vision test. Unbeknown to the participants, they entered a room with who they assumed to be other participants, but who were actually seven confederates. Each person in the room was then shown a picture of a target line next to three lines A, B, and C, and asked which line was most similar in length to the target line. The answer was always fairly obvious, however, the seven confederates would purposefully give the wrong answer. The real participant was the last to give his/her answer, after they had heard all the other answers. Asch found that over 12 different trials, participants conformed at least once 75% of the time, showing that people will often look to others for evidence and proof of what the correct answer is.4

To further investigate this notion, Asch continued to conduct experiments throughout the 1950s, which are known usually holistically referred to as the Asch conformity experiments. While the 1951 study showed that people will use social proof for answering a question, Asch was also curious to see whether it would change the way people behaved outside of an experiment. In 1962, he conducted the “Face the Rear” experiment. In this experiment, which was a stunt conducted in collaboration with the Candid Camera show which often recorded pranks on unassuming people,5 Asch examined people’s behavior getting into elevators. Confederates were already in the elevator and faced the back (an unusual behavior). Asch found that some people followed this backwards behavior and stood in the same direction as the confederates when they entered the elevator. These people did not know that they were being watched, suggesting that even outside of the laboratory, people look for social proof to know how to behave.

However, at the time, Asch named this social and psychological phenomenon herd behavior. It wasn’t until 1984 that the term social proof became popular, when Dr. Robert Cialdini, professor of psychology, coined it in his book Influence: The Psychology of Persuasion.1 In this book, Cialdini suggested that social proof was one of six key principles of persuasion. The book is now one of the cornerstone texts of marketing and social proof has become a phenomenon widely studied to better understand how to nudge and manipulate consumerist behavior.6


There are both positive and negative consequences to our tendency to use social proof to guide our behavior. It can inform us of the acceptable norms of a particular culture, or the standards that our employers want us to adhere to. It can help push people to wear masks during the COVID-19 restrictions because they don’t want to feel out of place. However, it can also cause people to disregard rules, regulations, or even science, as the influence of social proof is often stronger than other rules that govern behavior.

When we use social proof to inform our behavior, we are not necessarily acting rationally. Take Asch’s 1951 experiment – people were willing to go against obvious logic because of their desire to conform. Participants allowed social proof to completely change their answer and go against visual facts. Instead of thinking for ourselves, we passively adopt the behaviors of those around us, which can lead to something known as pluralistic ignorance. Pluralistic ignorance suggests that even though people might privately hold a belief different from the norm, they believe they are the only person who feels this way, so they continue to follow the norm.7 For example, even if you agree with the science that climate change is a pressing problem and people’s behavior needs to change, you might not actively do anything if those around you believe it is a hoax. This means that social proof can silence any voices or behavior that go against the grain.

When social proof occurs outside of an experiment, there can be really dire consequences. For example, it can motivate a mob mentality, where people act in ways they normally wouldn’t because of perceived group pressures. Even if someone intended to attend a protest peacefully, if everyone around them is being violent, they might be driven to do the same. Another scary outcome of social proof is known as copycat suicides. Copycat suicides are thought to be caused by social proof, where individuals read about a suicide in the media and it influences others to take the same action.8


Although various experiments show that people tend to bend their behavior in response to what people are doing around them, not everyone follows the crowd, or else we’d never have any kind of progress. Even in Asch’ 1951 experiment, 25% of people never conformed to the confederates.

John Berger, a social psychologist, realized that not all people tend to follow the crowd. He conducted a range of experiments to try and identify what factors influence whether someone or not uses social proof to inform their own behavior. In one study, he asked participants to choose an option from various consumer products that included paper towels, clothes, laundry detergents and music. Participants were told a peer would witness the choices that they made and form an impression about them as a result. Half the participants were told how another participant, who was a couple of years older, had chosen before them.9

Participants who were told that someone older than them had made certain choices were slightly more likely to follow their lead. However, the opposite was found when it came to their decisions on music and clothes – they were less likely to pick the same options as the older person.9

Although Berger’s experiment doesn’t negate the influence of social proof altogether, it does show that at times, our desire not to be like someone else (perhaps someone we find uncool or that we believe to have outdated views) is stronger.

Social Proof and E-Commerce

Social proof is often used as a marketing technique to get people to buy particular products. As marketers have come to learn about how strong a persuasive power social proof has on consumer behavior, they ensure to make their consumers believe that other people also purchase and like their product.

When in a physical store, consumers might decide to purchase a product based on the type of customer they see in the store or other people they see looking at the product. This kind of social proof isn’t possible when online shopping, so businesses have come up with other ways to suggest social proof. That can mean emphasizing customer reviews on your website, enabling a function that shows people on the site how many people currently have this item in their basket, or by including certifications on the web page to vouch for the credibility of the product. In fact, these days, there are a number of plugins that businesses can use that will help them perpetuate social proof, like Proof which personalizes the website for each individual that visits it.10

Social Media’s Role in helping contain COVID-19

Although we’ve discussed many instances where social proof can cause people to engage in irrational behavior, social proof can also be employed to try and encourage people to follow scientific health protocols.

Gaging what other people are doing has become increasingly difficult in light of the COVID-19 pandemic. Amidst work-from-home orders and lockdowns, one of the places that people turned to in order to see how others were behaving was on social media. Sometimes, this behavior wasn’t productive; people seeing pictures of empty shelves at the grocery store pushed them to go out and load up on what they deemed as necessary items. Remember the toilet paper shortage in April?11

However, in knowing that social media is a breeding ground for social proof, health officials can also be proactive in finding ways to encourage people to wear masks. They might ask celebrities to post a picture of themselves wearing a mask or following guidelines, or as we’ve seen pop up over the course of the pandemic, can ensure that anytime the virus is mentioned, users can see a link that guides them to official websites with official procedures and recommendations.

Related TDL Content

Three Thought Patterns that Let Advertisers Influence You on Social Media 

In this article, our writer Hannah Potts examines the different ways that we might be being manipulated on social media. The second reason that Potts identifies has to do with informational influence/conformity, where advertisers use testimonials and reviews to help us decide to purchase their product because we tend to seek out validation from others.

A Nudge For Coverage: Last-Mile Problems For Health Insurance

Prompted by a Wall Street Journal article that showed that despite the 2010 Obama Care Act, 30 million Americans are still uninsured, our writer Timothy Murphy examines ways that people’s participation in health care coverage can be increased through behavioral science nudges. More generally, Murphy examines how social proof can be used for various political agendas, from compliance to health coverage all the way to pushing people to vote a particular way.


  1. Farnam Street. (2017, May 19). Social Proof: Why We Look to Others For What We Should Think and Do
  2. Social Conformity Definition: Normative vs. Informational. (n.d.). Retrieved January 8, 2021, from
  3. Informational social influence: Conforming to be accurate. (2016, January 15). Open Textbooks.
  4. McLeod, S. (2018, December 28). Asch conformity experiment. Simply Psychology.
  5. Popova, M. (2012, January 13). The Psychology of Conformity. The Atlantic.
  6. Schenker, M. (2019, June 29). How to Use Cialdini’s 6 Principles of Persuasion to Boost Conversions. CXL.
  7. The Decision Lab. (2020, September 11). Social norms
  8. Miller, D. N. (2011). Copycat suicides. Encyclopedia of Child Behavior and Development
  9. Martin, S. (2017, July 7). The Science Behind Why Some People Don’t Follow the Crowd. Influence at Work.
  10. WooKeeper. (2020, December 14). 10 Best WooCommerce Social Proof Plugins of 2020
  11. Naeem, M. (2020). The role of social media to generate social proof as engaged society for stockpiling behaviour of customers during COVID-19 pandemic. Qualitative Market Research: An International Journal

About the Authors

Dan Pilat's portrait

Dan Pilat

Dan is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. Dan has a background in organizational decision making, with a BComm in Decision & Information Systems from McGill University. He has worked on enterprise-level behavioral architecture at TD Securities and BMO Capital Markets, where he advised management on the implementation of systems processing billions of dollars per week. Driven by an appetite for the latest in technology, Dan created a course on business intelligence and lectured at McGill University, and has applied behavioral science to topics such as augmented and virtual reality.

Sekoul Krastev's portrait

Dr. Sekoul Krastev

Sekoul is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. A decision scientist with a PhD in Decision Neuroscience from McGill University, Sekoul's work has been featured in peer-reviewed journals and has been presented at conferences around the world. Sekoul previously advised management on innovation and engagement strategy at The Boston Consulting Group as well as on online media strategy at Google. He has a deep interest in the applications of behavioral science to new technology and has published on these topics in places such as the Huffington Post and Strategy & Business.

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