Influence: The Psychology of Persuasion — Book Notes

Robert B. Cialdini

Published: 2006

Image for post
Image for post

Persuasion vs. Coercion


  • communicators try to convince other people to change their own attitudes/behaviours about an issue through transmission of message with free choice


  • Freedom of choice is removed


Fixed-Action Patterns

  • all of us have it

Why We Have It

  • automatic, fixed-action pattern of response is efficient most of the time

Weapon of Influence #1: Reciprocity

Rule of reciprocation: we should try to repay, in kind, what another person has provided us.

  • there is no human society that does not subscribe to the rule

The rule is overpowering:

  • Even if you dislike someone, you’ll still find the need to reciprocate.

Reciprocal concessions

  • general rule of reciprocity: a person who acts in a certain way towards us is entitled to a similar return action

Rejection-then-retreat Technique

  • Make a larger request of me, one that I will likely turn down

Weapon of Influence #2: Commitment & Consistency

  • we have a nearly obsessive desire to be consistent with what we have already done

Why consistency:

  • valuable and adaptive

What produces the automatic tape of consistency?

  • commitment

Foot-in-the-door technique:

  • start with a small request then gain eventual compliance over larger requests.

Commitment conditions:

  • you look at a person’s actions to decide what kind of a person he is


  • an exploitative individual can offer us an inducement for making the choice, then after the decision has been made, remove that inducement, because he knows that the commitment we have made will stand on its 2 legs.

Weapon of Influence #3: Social Proof

  • one way we use to determine what is correct is to find out what other people think is correct

Optimal Condition for Social Proof: Pluralistic Ignorance

  • in the process of examining the reactions of other people to resolve our uncertainty, we are likely to overlook a subtle but important fact — those ppl are probably examining the social evidence as well

Bystander Effect

  • failure of entire group of bystanders to aid victims in agonizing need of help

Why Bystander Effect occurs:

  • Diffusion of Responsibility — personal responsibility of each individual is reduced when more and more people are around

Optimal Condition for Social Proof: Similarity

  • we are more inclined to follow the lead of an individual who is similar to us

Weapon of Influence #4: Liking

  • We most prefer to say yes to the requests of someone we know and like.

Compliance professionals just need to get us to like them. How?

Factor 1: Physical Attractiveness

  • there is a click, whirr response to attractive people

Factor 2: Similarity

  • we like people who are similar to us

Factor 3: Compliments

  • You like people who like you

Factor 4: Contact and Cooperation

  • we like things that are familiar to us

Factor 5: Conditioning and Association

  • people blame the weathermen when the weather turns bad; people kill the messenger (in ancient times) when they brought bad news

Weapon of Influence #5: Authority

  • a multilayered and widely accepted system of authority has an advantage: allows the development of sophisticated structures for resource production, trade, defence, expansion and social control that would otherwise be impossible

There are factors that can convey authority, which affects us.

Factor 1: Titles

  • people can adopt the label without putting in effort and receive a kind of automatic deference

Factor 2: Clothes

  • cloak of authority is fakable

Factor 3: Trappings/Expensive Items

  • e.g jewelry, cars

Weapon of Influence #6: Scarcity

  • opportunities seem more valuable to us when their availability is limited

Scarcity Works Because:

  • 1) Familiar: we have a mental shortcut that tells us that things that are difficult to possess are typically better than those that are easy to possess.

Psychological Reactance Theory:

  • whenever free choice is limited or threatened, the need to retain our freedoms make us desire them significantly more than previously.

Scarcity Applies To Information:

  • we find a piece of information more persuasive if we think we can’t get it elsewhere

Limited Number Tactic:

  • customer is informed that a certain product is in short supply that cannot be guaranteed to last long.

Deadline Tactic:

  • some official time limit is placed on the customer’s opportunity to get what the compliance professional is offering

Like what you’re reading? Then join my monthly reading recommendations newsletter where you’ll get more of such book notes (+ what I think you should read!):

Written by

Marketing @ahrefs

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store