How to Persuade People

I recently read Influence: The Psychology of Persuasion by Robert B. Cialdini. It is a short and interesting book. Considering the things happening in Romania in the last weeks I thought it would be a good idea to summarize here some of the ideas from the book.


Cialdini talks about 6 ways of persuading people:

  1. Reciprocity
  2. Consistency
  3. Sympathy
  4. Authority
  5. Social proof
  6. Scarcity


Think about the free food sample you get in the supermarket. There are a lot of reasons for companies to offer them. Even if you refuse them or if you don’t like them that much, afterwards the chances to buy that product are pretty big.

A good¬†example from the book is a little experiment a professor made. On Christmas he sent greetings cards to random people. Most of them responded back, even though they didn’t knew him.

Another important thing to have in mind is that when you get a small gift you will probably feel indebted to return the favour. And often you will give that person a bigger gift or favour.
There is nothing wrong to receiving and giving gifts. The thing is that when you receive something from someone, without an apparent reason, they choose what to give to you. And afterwards they ask for something from you, maybe a particular thing or a favour. They choose what to give to you and they also choose what to receive in return. Doesn’t seem fair.

I like to think that there are no free stuff.


I usually see consistency as a good thing, but you really need to be careful with this.
When you take a decision you do it based on what you know and expect in that particular moment. A lot of times things change afterwards. Maybe you receive a new information, maybe one of the initial factors change. When something new appears, it would be a good moment to rethink your decision and see if you are still ok with it. It is alright to change your mind.

I know, easier said than done.
Have you ever received a phone call from a company doing some research about their product or about one of their services ? Or maybe someone knocked on your door ?
They usually say they have 2 or 3 questions to ask and it won’t take longer than 2 minutes. And you say “yes”. After the first 15-20 questions you start thinking that maybe it would have been a good idea to say “no” instead.


Multi-level marketing (MLM) organizations work based on this one.
It’s hard to say no to people you know, people you like, or to your family.
“You don’t need to buy anything, just come and listen to them”. “You don’t need to sell these products to other people. Just buy what you need and you will get a discount. Maybe from time to time you can also help a friend and get them something they need”.

Don’t ask your friends to buy something from you just because you know them.
Sure, I know it works, but it is wrong. Think about Avon, Amway, Herbalife, Oriflame, etc.

Another good example would be the different public figures (so called stars – athletes, singers, actors, etc.) you see on commercials on TV. This is also the reason you hear about them supporting some politician.
It makes you buy a product or vote for a particular politician just because someone you like supports it.


The best example would be the Milgram experiment.

The best method of defense against this is to ask ourselves two questions:

  • is that authority figure an expert on that subject?
  • how is he?

Social proof

This is a bit tricky. An easy example would be the laughters you hear while watching a comedy series.
Hearing other people laughing at some jokes makes you also laugh. Laughing at something makes you think that that thing is funnier than it really is.

Other darker examples would be from small religious cults. Being part of a group makes you do things that you wouldn’t do if you were alone. You can read about the Seekers cult from Chicago. I also recommend watching the movie The Joneses.


I think everybody knows about this but for some reason all people choose to ignore it.
If something is rare (or appears to be rare) we expect for it to also be expensive and we also expect it to be a good deal.
Best examples ? “Huge one day sale”, “Limited offer”, “Black Friday”, “if you don’t buy it now I have another customer that is ready to pay good money for it” ..


Is hard to defend against all of these. The first step is to know about them. It is also really important to observe how we act when we are under these kind of influences. Afterwards it will be easier to avoid them or to see some red flags when we are acting in a certain way.