The 6 Principles of Persuasion

Today I want to share with you what I learned from a book that I recently finished: Influence: The psychology of persuasion by Robert Cialdini. His book goes through the six ways to persuade others: reciprocation, commitment & consistency, social proof, liking, authority and scarcity. Here, I will quickly summarize each concept.

1) Reciprocation

Do you like having the feeling that you owe someone something? Probably not. When someone has done us a favor, we tend to reciprocate. This has always been the case, even in tribal times. This has allowed for the division of labor and the exchange of goods. To prove this a university professor did a small experiment by sending out Christmas cards to many random people. While he expected a couple of letters back, he was perplexed to find out that almost everyone – people he didn’t know – responded with plentiful of best wishes.

We feel social pressure to reciprocate. Have you ever helped a friend move into a new place? You know very well that when you move you can call on their help. Reciprocation. If you want to have more people come help and you think you won’t find enough people, send all your targets a card a week in advance telling them how much they mean to you. I promise you it will increase the chance of them showing up to help you move.

We often reciprocate disproportionally; large reciprocal responses can be triggered by providing someone a small favor. This is why a woman allowing a man to buy her drinks (willingly or unwillingly) is seen as sexually more available (by both genders) to the man buying drinks. Reciprocity forces uninvited debt.

This is one of the reasons you should always be good to the people close to you. Doing them small unsolicited favors are likely to be returned disproportionally. Some people call this Karma. Give, and you shall receive.

2) Commitment and Consistency

In general we stick with our commitments. Now, obviously you can think of many moments where this isn’t true, but generally speaking we remain consistent with what we say we will do. We like to be consistent with what we say and do; it’s a socially appealing characteristic. If I were to ask you whether you would give money to the homeless, you might be tempted to say yes in order to look good. What then happens is that next time we walk by a homeless person all I need to do is look at you and you will reach for your wallet.

One study showed this phenomenon by calling households to ask if people were willing to volunteer for a couple of hours if asked by charity. Many people responded positively, not knowing they would be called a week later to be asked just that. It turned out that the group who had been asked beforehand whether they would commit had a much higher chance of actually volunteering. The number of volunteers was 700% higher than the control group in which people weren’t called beforehand to ask about the hypothetical situation.

You can use this too. Let’s say you want to go to a movie of which you know your best friend doesn’t want to go. Instead of saying “Can you please come watch that movie with me?” you could try asking a different question first: “Would you go see a movie with me that you might not enjoy as much as I do?”. Your unsuspecting friend will probably answer with yes, to which you can then respond with your request for the movie. As they have just agreed, they will find it a lot harder to now say no.

3) Social Proof

People are influenced by the behavior of others. Especially when we are not sure how to respond to a certain situation, we tend to look around and copy others’ behavior. At an unfamiliar event or situation, we look to others for correct etiquette. Tip jars are usually ‘salted’ by having money already placed. This effect is amplified by how similar the person whose actions we are watching are to ourselves.

I once saw the effect of this in a Youtube clip, which I unfortunately cannot find anymore. The situation was that of a waiting room of a doctor. 8 people that were actors in the experiment stood up from their seats every time a certain sound went off. They all did this quietly, without talking and continued doing what they were doing once they sat back down. The one or two individuals who had no idea what was going automatically copied the behavior of the actors. It was interesting to the faces of the subjects. You could see the bewilderment on their faces, but they still complied. We conform in groups, even if we don’t understand or agree with the behavior a group demonstrates.

4) Liking

We are more easily influenced by those we like. If your best friend tells you you NEED to buy a certain product, the chance of you actually buying it is a lot higher than when a person who you dislike tells you. You trust those who you like, and it makes you more susceptible to being influenced.

Studies have demonstrated that we automatically attribute positive traits such as intelligence, honesty and talent to attractive people. It is therefore no co-incidence that ‘attractive’ political candidates often beat unattractive rivals. Have you ever read up on the first televised American Presidential debate? It was the year 1960 and it was Nixon up against Kennedy. Nixon didn’t want to have any make up put on him, whereas Kennedy understood the concept of liking. Kennedy understood that looking good helps being interpreted as being capable. Nixon famously ended up as the loser of the debate; many would agree because he was sweating and looked awkward. Funnily enough, people who listened to the radio rather than watching it on TV found that Nixon won the debate.

We like people who seem similar. They are like us, so they understand us and it feels safe. This is why we try to find areas of shared interest when we want people to like us more.

5) Authority

Perhaps the most straightforward one to understand, but we are influenced by people who have perceived authority. My favorite example is that of the Stanley Milgram experiments, where participants willingly delivered seemingly deadly shocks to people.

If your boss or manager asks you to do something, there is a high chance you will do it, simply because they are your superior. It’s harder to refuse a demand from a superior rather than your peer, simply because of authority.

6) Scarcity

When we fear losing something, we tend to comply with a request much easier than if we are trying to gain something. The result is that we see something as more desirable when it is scarce.

I’m trying to buy a house in Rotterdam, where the housing market is booming. Everyone knows that you need to overbid in order to acquire a house here. To add pressure real estate sales men organize “open house days” for popular houses, where you don’t need to make an appointment to view a house; everyone can walk in. They say they do it because it’s easier, but there is a smart mechanism behind this decision. The sales men know that when I see 10 other buyers in the house that I want I am willing to pay a lot more than if I thought I had little competition.

On top of that, they tell everyone that they have 3 days to place a bid and that the buyer with the most favorable conditions for the vendor will get the house. Not only do I have to be scared of my competition, I now have time pressure as well.

In these high pressure environments an item will be sold for a higher price because of fear of losing out. No longer am I focused on carefully evaluating whether this house is my dream house. Rather I am focused on the desire to own the place and as a result I bid a lot higher than I would rationally want.