Notes from 'Influence: The Psychology of Persuasion'

The 6 principles of persuasion are Reciprocation, Commitment and Consistency, Social Proof, Liking, Authority, Scarcity.


These 6 ways to influence people were first put forward by Robert B. Cialdini in his 1984 book called “Influence: The Psychology of Persuasion.”


Here is a summary of 6 principles of persuasion, which from James Beswick’s customer review:

  • Reciprocation

    I do you a favor, and you are predisposed to do the same thing for me. Those free food samples at Costco aren’t so free after all.

    Contrast: Extreme positions make less extreme positions more palatable - You are more likely to spend $100 on a shirt if you already spent on a suit, and the good cop is more likely to win your confession after the bad cop has done his work.

  • Commitment and Consistency

    Studies show that gamblers are more convinced of a horse’s capability to win after placing the bet versus before the bet. Placing a commitment causes more loyalty to an idea.

    People will defend a position once they take it - Competitions that ask you to describe the virtues of a product in 15 words or less essentially convert you to promote positive messages of that product to other people, since you will aim to be consistent with yourself.

  • Social proof

    People will look to others to aid their decision-making process. If “people like you” claim to like an idea, chances are that you will too (hence canned laughter in TV shows).

  • Liking

    You are more likely to accept an idea from a person you like. Studies show that attractive people have twice the likelihood of con vicing others than average-looking individuals, and salespeople are frequently trained to feign interest in your hobbies and mirror your body language for the same reason.

  • Authority

    If those we respect take a position, we’re more convinced by its validity. From the sales frenzy over Sarah Palin’s glasses to the use of celebrities to endorse products, authority is a trump card in persuasion.

  • Scarcity

    We are driven to ideas that seem scarce - Hence the use of the “Buy now, offer won’t last!” approach to sales, or the use of high prices to create exclusivity.


After reading the book “Influence”, I have gained a psychological level of understanding of some business activities and social phenomena. In the future, when facing similar psychological manipulation, I should be able to keep a clearer head and think independently to avoid being easily misled.