• David de Souza

'Yes!: 50 Scientifically Proven Ways to Be Persuasive' Summary

Updated: Sep 3



Due to our desire to be consistent, our beliefs don't often change, even when it is not in our self-interest. The most interesting takeaway from this book was the idea of helping people to free themselves from this consistency bias by telling them: "your decision was correct at the time you made it" and "the precious decision was the right one given the evidence and information you had". Want to dig deeper than the core principles? Check out: • 80/20 Text Notes 80/20 Mind Map




Core Principles:


I have taken the lessons from 'Yes' and distilled them into 18 core principles:


  1. To overcome the effects of peoples' consistency bias, avoid framing their commitment as a mistake. Tell them: "Their decision was correct at the time they made it"

  2. Free them from the previous commitment. Tell people: "The precious decision was the right one given the evidence and information they had".

  3. There are 3 major factors that influence reciprocity: • Significant: When a waiter gave two candies with the bill it increased tips by 3.3% (compared to no candy) to 14% with 2 candies. •Unexpected: One candy was expected and so when a second was given it inflated the tip. • Personalized: The more personalized the request, the more likely the person will agree.

  4. A recipient places more value on a favor compared to the person who gave the favor initially. However, as time goes on the value decreases in the receiver's mind but increases in the givers.

  5. Before you get to the toughest request (On a call to a customer service agent) tell the person how happy you are with their service and that you are going to write a letter of appreciation. After you have their manger's details, ask for one final request.

  6. Mirroring increases Trust. In negotiations mirroring resulted in deals 67% of the time compared to 13% (without mirroring).

  7. Matching Verbalization: Repeating back what a customer ordered increased tips by 70%.

  8. Due to loss aversion, it is usually more persuasive to mention what you would lose instead of what you'll save.

  9. Sad buyers are willing to pay 30% more on average compared to neutral buyers. Sad sellers are willing to sell an item for 33% less than a neutral buyer.

  10. Increased choice can result in increased frustration.

  11. If you have an area in which your leverage is weak, mention it during negotiations, to make you seem more trustworthy.

  12. Mentioning a drawback (or something against your self-interest) makes you more trustworthy which puts you in a better position to promote your strengths.

  13. The word "because" acts like an automatic reflex to get someone to do something.

  14. When given a bonus gift for purchasing a product, the value of the bonus gift will decline. To overcome this instead of writing: "Receive a free Ecourse" change it to: "Receive a $500 Ecourse at no cost to you.

  15. People are more likely to be persuaded if they have taken a small step in the right direction as long as the first step was made voluntarily and without coercion. The momentum will propel them to carry on.

  16. Give a person the label of a certain trait and then make a request consistent to that trait (and provide examples of when they have done that).

  17. After a person has answered a question favorably, say "I'll let the others know" to increase commitment as their decision has now been publicly declared.

  18. Ask someone why they support an initiative. This will reinforce to themselves the reasoning.


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The 80/20 of Worldly Wisdom: