Blog 2022 12 03 Influence: The Psychology of Persuasion by Robert B. Caldini

Influence: The Psychology of Persuasion by Robert B. Caldini

An easy-to-read book for those who want to learn about how influencing others works. It’s not only useful to learn how to influence other people but also to understand how others try to manipulate you.

Organized around seven chapters, seven main ideas.

  • Weapons of Influence
  • Reciprocation: The Old Give and Take and Take
  • Commitment and Consistency
  • Social Proof: Truths are Us
  • Liking: The Friendly Thief
  • Authority: Directed Dereference
  • Scarcity: The Rule of the Few

Let me pick three of them to explain a little bit more in detail.

Reciprocation: The Old Give and Take… and Take

I included this rule because it’s so evident and at the same time I already wrote about a similar effect, but the other way around. In The Seniority Trap I wrote that if you ask for something small and people give it to you, they will find you more likeable. They will do so because they want to stay consistent with themselves, they want to justify the help they provided.

This rule approaches giving and taking from the other direction. Give something so you can take back - a lot more. We all know that there is no free lunch. This expression has many slightly different meanings, but they essentially all boil down to this: if someone gives you something seemingly for free, you can rest assured that you’ll be expected to give something in return.

I remember that during university we were invited by a classmate of ours to a presentation about a multi-level marketing scheme.** We liked the guy, we didn’t want to turn him down (Chapter 5, Liking: The Friendly Thief) so we went. Of course, we were invited to take some drinks, and have some crackers at a moderately nice hotel. It was clear to us that we didn’t want anything from that spectacular opportunity. In the end, we said so. They said no problem, but maybe we can just share some friends’ phone numbers who we thought would be interested.

As they already gave something, it was difficult to resist. I knew I could, I don’t remember the others. But on another occasion, where all this happened one on one, even though I really didn’t want, I gave in and shared a bunch of numbers. For a beer basically…

If you are the influencer, it’s a good idea to offer some tokens, buy some drinks, share some free content before you ask your potential customers to buy something. They will feel they owe you something.

If you are on the other side and you recognize what’s going on, just turn down, don’t buy, don’t give. As the aothor says, “simply take whatever the inspector is willing to provide — safety information, home extinguisher — thank him politely and show him out the door. After all, the reciprocity rule asserts that if justice is to be done, exploitation attempts should be exploited”

Commitment and Consistency

As already mentioned in the previous section, we will even make ourselves like someone more just to stay consistent. But there are even funnier studies. Apparently, “after placing a bet at a horse track, gambles are much more confident of their horse’s chances of winning than they are immediately before laying down that bet. Of course, nothing about the horse’s chances actually shifts; it’s the same horse, on the same track, in the same field; but in the minds of those bettors, its prospects improve significantly once that ticket is purchased.”

When you commit to something, you’ll feel more sure about your decision.

The author shared some other examples. For example, toy manufacturers often understock toys at the same of running some serious ad campaigns before Christmas. Your kid asks for a specific gift, you commit, you want to buy, but as it’s out of stock, you come home with something different. Then in January, or February, they restart the ads. Your kiddo still wants it and asks you to get it. As you already promised… Horrible, isn’t it?

Another form of this commitment consistency is related to initiation ceremonies. Whether such ceremonies are for tribal or fraternal societies, usually they are not funny and enjoyable, but rather rough and aggressive, maybe even barbaric. Authorities often try to do against them, but it doesn’t matter. They will not disappear. Those who gain access to a group in such a difficult way will convince themselves that the group is more worthy and valuable than otherwise. Such rites and ceremonies are vital for the survival of a group. The more difficult to get in, the more valuable it will be regarded and the more loyal the members will be.

Scarcity: The Rule of the Few

The last rule I wanted to mention is about scarcity. When you think that there is difficult to get something, because all the other instances were taken, or simply not many were constructed you’ll attribute more value to that thing. When you think it’s a never returning opportunity to visit a place, you’ll often want to visit it even if otherwise you’d not be interested at all.

The author shared a story about when he wanted to visit a Mormon church. It turned out that he had no interest in it all. But it was advertised as once in a lifetime opportunity. Normally you cannot enter the most sacred part, if you’re not a Mormon, only during major (re)constructions. He got really excited about the possibility. Finally, a friend asked him some questions and realized it was only about the scarcity of such opportunities, not his interest in the architecture of the church.

When you’re selling something, you can take benefit of this mindset. Try to invite everyone at the same time and then queue them. People who are not the first will be very excited and even stressed hoping that the previous person in the queue won’t take the good they came for. And they will be also more inclined to make an offer because they know that in a few minutes there might not be any good to make an offer.

Another interesting manifestation of the scarcity mindset is related to revolutions. Interestingly revolutions don’t break out when people are kept in the most severe deprivation. They suffer, but they usually take it. Then someone comes who is either weak or just believes that people should be given more freedom. Society gets a bit of fresh air.

Then usually the ruling class is unhappy, why give more freedom than necessary? So someone else will take over and start hardening the order. And that’s the moment when people are getting furious and trying to overthrow the order. When they felt that a resource (freedom) they just got started to become scarce commodity.


Influence is an easy to read and entertaining book about how our minds work, how persuasion works. I find it a very useful read for everyone. Maybe you don’t want to influence others and you think you don’t need this book. Still, I think it’s useful to understand how others try to influence you! Understand what kinds of games they are playing on you and you’ll be able to recognize their tricks, resist and reject only seemingly advantageous deals.

A recommended read!

Connect deeper

If you liked this article, please

This post is licensed under CC BY 4.0 by the author.

C++23: auto(x) and decay copy

C++23: std::out_ptr and std::inout_ptr

Comments powered by Disqus.