Book notes: Contagious by Jonah Berger

Contagious by Jonah Berger book summary review and key ideas.

Contagious: Why Things Catch On by Jonah Berger


“Why do some products get more word of mouth than others? Why does some online content go viral? Word of mouth makes products, ideas, and behaviors catch on. It’s more influential than advertising and far more effective.

Can you create word of mouth for your product or idea? According to Berger, you can. Whether you operate a neighborhood restaurant, a corporation with hundreds of employees, or are running for a local office for the first time, the steps that can help your product or idea become viral are the same.

Contagious is filled with fascinating information drawn from Berger’s research. You will be surprised to learn, for example, just how little word of mouth is generated online versus elsewhere. Already praised by Dan Ariely and Dan Gilbert, and sold in nine countries, this book is a must-listen for people who want their projects and ideas to succeed.” -Audible

Opening thoughts:

I forgot why this was on my list but perhaps it was recommended by Audible. As a default for a clear majority of my choices, it had a high number of reviews and a high average rating. I also think I chose this book because this past year and this upcoming year I’m going to be creating more content with project a few projects I’m currently planning out. I figured this would be a good subject to study and learn about this month.

Key notes:

  • One reason why things take off is because they’re simply better
    • Another reason is attractive pricing
    • In similar products, cheaper one wins out 
  • Advertising also plays a role
  • Social transition: social influence and word of mouth
    • Word of mouth has a significant impact on what we think, read, but, and do
    • Word of mouth is the primary factor behind 20-50% of all purchasing decisions
    • Word of mouth is more persuasive for 2 key reasons:
      1. It’s more persuasive
      2. Word of mouth is more targeted
    • Despite the rush to social media by companies, only 7% of word-of-mouth happens online
      • We spend at least 8x more with off-line interactions then online ones, but it’s hard to keep track of and quantify
  • Contagious content is like a good joke
    • It is inherently viral that it spreads regardless of who is doing the talking

Reader’s note: Okay, he just spent 45 minutes of the six hour book on pure set up and hasn’t really given any substantive ideas yet. The author could have definitely whittled down all of the set up and gotten to the meat faster.

Six Key Principles / Steps to Contagious Content

  • Principle 1: Social currency
    • How does it make people look to talk about a product or idea?
    • Make people feel like insiders
    • Leverage game mechanics to give people ways to achieve and provide visible symbols of status that they can show to others
  • Principle 2: Triggers
    • How do we remind people to talk about our products and ideas?
    • Triggers are stimuli that prompt able to think about related things
  • Principle 3: Emotion
    • When we care, we share
    • Craft ideas and messages that make people feel something
  • Principle 4: Public
    • Can people see when others are using our product or engaging in our desired behavior? 
  • Principle 5: Practical value
    • How can we craft content that seems useful?
  • Principle 6: Stories
    • What broader narrative can we wrap our idea?

Chapter 1: Social Currency

  • If something is supposed to be secret, people are more likely to talk about it
  • Social currency: people share things that make them look good to others 
    • We are hardwired to get pleasure from sharing our experiences and talking about ourselves
    • People use social currency to achieve desired positive impressions among their families, friends, and colleagues
    • Talking about remarkable things provides social currency
      • Remarkable things are defined as unusual, extraordinary, or worthy of notice or attention
        • The Blair Witch Project: $35,000 budget, $248 million gross worldwide
    • Emphasize what’s remarkable about a product or idea, and people will talk
  • Game mechanics are the elements of a game including rules and feedback loops that make them fun and compelling
    • Good game mechanics keep people engaged, motivated, and always wanting more
    • People don’t just care how they’re doing, they care about their performance in relation to others
      • Like many other animals, people care about hierarchy
        • Humans like feeling high status, but status is inherently relational
  • Third way to generate social currency: make people feel like insiders
    • The fact that something isn’t readily available can make people value it more
    • The moral of something like fantasy football and people investing time into it for free is that people don’t need to be paid to be motivated
      • As soon as you offer to pay people to refer other customers, any interest they had in doing it for free will disappear

Chapter 2: Triggers

  • Immediate and ongoing word-of-mouth is important
    • Sights, smells, and sounds can trigger related thoughts and ideas, making them more top of mind
  • Consider the context – think about whether the message will be triggered by the everyday environments of the target audience
    • Strong and unusual links are better – It is important to pick triggers that happened near where the desired behavior is taking place
    • Awe is the sense of wonder and amazement that occurs when someone is inspired by great knowledge, beauty, sublimity, or might
      • It’s the experience of confronting something greater than yourself
      • Awe expands one’s frame of reference and drives self transcendence
      • It encompasses admiration and inspiration and can be evoked by everything from great works of art, music, religious transformations, breathtaking natural landscapes, human feats of daring and discovery

Chapter 3: Emotion

“The most beautiful emotion we can experience is the mysterious. It is the power of all true art and science. He to whom this emotion is is a stranger, who can no longer pause to wonder and stand wrapped in awe is as good as dead”

Albert Einstein
  • Studies show that positive articles were more likely to be highly shared than negative ones
    • Another study showed that articles that evoked anger or anxiety were more likely to be shared 
    • Arousal is a state of activation and readiness for action
      • Humor is a high arousal emotion
      • Sadness and contentment are low arousal emotions
  • Focus on feelings
  • Book reference: Made to Stick by Chip & Dan HeathThe Three Why’s to find the emotional core of an ideaWrite down why you think people are doing something, then ask “why is this important?” 3 times
    • Arousal of any kind, emotional or physiological, can boost transmission and sharing

Chapter 4: Public

  • Public visibility – If something is built to show, it is built to grow 
    • People tend to conform to what others are doing
      • This is called social proof
    • Social proof is why some people turn down kidney transplants even though they need it because other people have rejected it, or why people assume the restaurant with a long line has the best food
    • Social influence is stronger when behavior is more observable
      • Observable things are also more likely to be discussed
      • A product, idea, or behavior advertises itself when people consume it

Chapter 5: Practical Value

  • People like to pass on practical, useful information
    • News others can use
    • Passing on useful things strengthens our social bond
  • Judgments or decisions aren’t always rational or optimal
    • Instead they are based on psychological principles of how people perceive and process information
  • Reference points make some deals seem better than others

Reader’s note: This is the same as the Contrast Principal referenced in other books like Never Split the Difference or Influence I believe,

  • Diminishing sensitivity reflects the idea that the same change has a smaller impact the farther it is from the reference point
    • Content that is obviously relevant to a narrow audience may actually be more viral
  • Just like the false information about autism and vaccination in 1998, bad information can spread just as quickly as good information
    • Therefore it’s always best to verify before you share

Chapter 6: Stories

  • The key is making valuable virality
    • Virality is most valuable when the brand or product benefit is integral to the story
      • In stories, critical details stick around while irrelevant details fall off
  • If you want to craft contagious content, try to build your own Trojan horse, but make sure you think about valuable virality
    • Make sure the information you want people to remember and transmit are critical to the narrative
  • Similarly to the effect of influencers, big forest fires aren’t caused by big sparks
    • Lots of individual trees have to catch fire and carry the flames
      • Contagious products and ideas are like forest fires

6 Principles that Drive Things to Catch On

  • Social currency – we share things that make us look good
  • Triggers – top of mind, tip of tongue
  • Emotion – when we care, we share
  • Public – built to show, built to grow
  • Practical value – news you can use
  • Stories – information travels under the guise of idle chatter

Main ideas / Themes:

Contagious content is like a good joke

  • Contagious content, like a good joke, is inherently viral because it spreads regardless of who is doing the talking
  • Social currency – people share things that make them look good to others
  • People don’t just care how they’re doing, they care about their performance in relation to other
  • Consider the context – think about whether the message will be triggered by the everyday environments of the target audience
  • Focus on feelings – Things that arouse us are more likely to be shared
  • Public visibility – If something is built to show, it is built to grow. Social influence is stronger when behavior is more observable
  • People like to pass on practical, useful information
  • Make sure the information you want people to remember and transmit are critical to the narrative

Closing thoughts:

This was a solid book about crafting contagious content that’s designed to go viral. I really enjoy how it breaks down the principles of what makes something viral, and then goes into detail on the 6 principles for things catching on.

There are a lot of concepts in this book that I’ve definitely heard of before when it comes to viral content and what makes things more shareable than others (i.e. things that arouse us, things with practical value, things that give us social currency, etc.) but this put it into words and a framework that was easy to digest.

I wouldn’t recommend this book to everyone because it deals with a very specific field / topic. This is definitely a great resource if you’re in a position where you are creating content or work in some sort of marketing/advertising aspect. While it’s not very nuts-and-bolts, and if you’re familiar with this subject you might not get a ton of value, but it does cover the topic broadly enough for anyone just getting into it.

For me, one of the big themes this year and next year is going to revolve around creating content, so this is very useful for me to keep in mind. I’m also going through an online course for creating a YouTube channel called Viral Academy from the company Jumpcut, and it talks about many of the same principles for viral content.

Overall, great read if this subject is something you want to learn more about. There may be other, better books out there, but this is a great starting point.

One Takeaway / Putting into practice:

Since the content I want to create in the future will most likely focus on either 1) adding value through knowledge/information or 2) value in the form of humor/entertainment, my one takeaway for this book will be:

  • Awe is the sense of wonder and amazement that occurs when someone is inspired by great knowledge, beauty, sublimity, or might

I think if I focus on creating content that truly opens people’s eyes and brings insightful/useful information to them, or even a look into a world/subject/field they never knew about, I’ll be able to grow the brand. In context, I’m thinking about applying this to building out my upcoming podcast for this next year in 2020. I also want to expand my Yolocruz Book Club brand out a bit more with this too and find ways to create awe in what people will learn.

The second focus would be creating hilarious content that focuses on creativity and funny concepts that will strike up the same emotion in people. I imagine it would be a sort of awe, because I don’t want my style to be just shallow humor. I also want to have some depth and thought put into the content.


Six principles about creating contagious content revolving around a product or idea.

Similar books:


Rating: 3 out of 5.


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