• David de Souza

Contagious: Why Things Catch On


If I were to sum up this book in one sentence it would be: People share things that make them look good. Keep this in mind when you are writing an article or building a product and it will go a long way in making people talk about it.

Want to dig deeper than the core principles? Check out:



Core Principles:


I have summarised 'Contagious', distilling the book into 12 core principles:

  1. People share things that make them look good. We don't share things that make us or others look bad.

  2. Remarkable things make people who talk about them remarkable and give them social currency.

  3. Create surprise by breaking a pattern that people have come to expect.

  4. Voting location has a big impact on how people vote. More than 10,000 people voted for school funding when the voting location was at a school.

  5. Most conversation is small talk. We are simply looking for something to say to avoid silence and to keep the conversation going. We usually talk about whatever is at the forefront of our mind.

  6. Useful, interesting, and awe-inspiring articles are shared 30% more.

  7. High arousal emotions make people share more because they motivate them to action. High Arousal/Positive Emotions: Awe. Excitement. Amusement (humor) High Arousal/Negative Emotions: Anger. Anxiety. Disgust. Low Arousal/Positive Emotions: Contentment Low Arousal/Negative Emotions: Sadness

  8. Focus on feelings instead of functions (of the product).

  9. Be careful when your heart is racing, such as after a crash or during turbulence, you may share more than you should.

  10. Stories are more perusable than facts for 2 reasons: 1. It's difficult to argue against something that happened to a specific person unless we were there. 2. We become distracted in the drama of the story and don't have the cognitive resources to reason or question, and we are therefore more likely to be persuaded.

  11. Remember STEPPS: Social Currency - We share what makes us look good. Triggers - What's top of the mind, will be on the tip of our tongue. Emotion - High arousal = Shareable Public - Design your product so that it can be shown. Practical Value - Content that is useful. Stories - It is harder to argue against a story.


Let me know how these summaries can be improved? Contact me via Email (david@thisdomain.co) or on Twitter.



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