Pluralistic Ignorance – Why Crowds Make You Stupid

Pluralistic Ignorance and Social Proof

The topics of social proof and pluralistic ignorance are explored by Dr. Robert Cialdini in his excellent book Influence: The Psychology of Persuasion. In the book, Dr. Cialdini reveals the six things that influence human behavior and decisions, and social proof is undoubtedly one of the most powerful.


Kitty's demise

One particularly riveting section of the book is where he tells the tragic story of Kitty Genovese, a young woman who was chased and brutally murdered on the street in New York City as she returned home in the early morning in 1964. What makes this story even more tragic is the fact that the incident was punctuated by multiple attacks over the course of about 30 minutes. Even worse, several of Kitty’s neighbors heard her screams and even looked out the window to see what was going on, but no one did anything about it until it was too late. While the initial newspaper reports claiming that there were 37 witnesses proved to be inaccurate, the police investigation revealed that there were at least a dozen people who had witnessed at least some part of the prolonged attack.

Dr. Cialdini describes how pluralistic ignorance affected the witnesses to Kitty’s murder. Our brains constantly scan our environment for data, and then our brains try to interpret what the data mean, and whether it has any relevance to us. The primary way it does this is by comparing the incoming information against patterns already stored in memory. When your brain encounters a situation that is unfamiliar, it starts working to figure out what is the most appropriate response. And, one of the primary ways it does that is to look for clues in the environment. Without a doubt, the type of clue that your brain places the most emphasis on is the reaction of other human beings who witnessing the same event.

What is going on?

In the case of Kitty Genovese, it is likely that many of the witnesses weren’t really sure what was happening. In fact, some of the witnesses testified as much, stating that they weren’t sure if she was just having a fight with someone, or was just coming home from a bar and was being generally loud and obnoxious. So, without sufficient information to determine what the appropriate response was, what would the witnesses naturally do? What would you do? If you’re like them, you would look into the windows of your neighbors to see how they are reacting. Unfortunately, those neighbors are watching the same unfamiliar situation and are looking back at you for clues on how to respond.

This phenomenon is what’s known as pluralistic ignorance. It is a situation where something happens in front of multiple people but, because it is unclear whether that situation requires action, no one does anything. Unfortunately, there are many examples of this phenomenon where people have died unnecessarily with people who could easily have helped them standing all around.

News magazine fodder

You have likely seen examples of this, conducted as social experiments on news magazine shows, where they test the good samaritan effect in cities. In one example, there is an actor lying on the ground in a crowded area with people walking all around, to see how many people actually stop to see if he is ok.

Dr. Cialdini describes experiments testing this same phenomenon in his book and found that, the more people who witness the event, the less likely it is that someone will do something. This is due to an effect known as diffusion of responsibility, which compounds the problem of pluralistic ignorance. In that scenario, even when a few people recognize that something needs to be done, it’s not clear who should be the one to do it. So no one does anything, because everyone is expecting someone else to.

I hope you liked this first part of my social proof series. If you did, please leave a comment below.