People will do things they see other people are doing.

Social proof, a term coined by Robert Cialdini in his 1984 book, Influence, is also known as informational social influence. It’s a cognitive bias that describes how we tend to be heavily influenced by what others around us are doing.

Social proof is considered prominent in ambiguous social situations where people are unable to determine the appropriate mode of behavior, and is driven by the assumption that the surrounding people possess more knowledge about the current situation.

Human beings are one of many social species, along with bees, ants, and chimps, among many more. We have a DNA-level instinct to seek safety in numbers and will look for social guidance of our behavior. This instinct creates a cohesive sense of cooperation and culture which would not otherwise be possible but also leads us to do foolish things if our group is doing them as well.

Sometimes referred to as Herd Mentality, Social Proof is a heuristic (or shortcut) where we rely heavily on the thoughts and actions of our peers when making decisions. This tendency is even stronger when we are feeling uncertain.

The key idea is that in any given situation, and especially when we are confused or under stress, our choices will lean towards following the crowd.

  • People instinctively queuing up in a line to wait for something
  • The peer pressure felt by teens when their friends are doing something
  • The tendency for people to stop and look at something when other people are already looking at it
  • How articles or images on the Internet that have many likes or shares tend to get even more
  • The tendency to outwardly agree with something we actually disagree with when in a group setting

Social Proof is one of the major cognitive biases and can be used by salespeople and other persuaders to heavily influence our decisions.

The canned laughter you hear in some TV comedies is designed to make you think the show is funnier than it otherwise might be. As annoying as it is, many studies have shown that simply adding canned laughter can increase the perceived funniness of a show.

Automobile commercials that say things like “The number one selling car” are using Social Proof to make you think more favorably about that particular car. All those people couldn’t have chosen poorly, right?

Product testimonials are another example of Social Proof in advertising. Ideally, you will be presented with an ad that lists people just like you that the product has already helped.