Contagious: Why Things Catch On

by Jonah Berger

People share more than 16,000 words per day and every hour there are more than 100 million conversations about brands.

A word-of-mouth conversation by a new customer leads to an almost $200 increase in restaurant sales. A five-star review on Amazon.com leads to approximately twenty more books sold than a one-star review. Doctors are more likely to prescribe a new drug if other doctors they know have prescribed it.

But want to know the best thing about word of mouth? It’s available to everyone.

The actual number is 7 percent. Not 47 percent, not 27 percent, but 7 percent. Research by the Keller Fay Group finds that only 7 percent of word of mouth happens online.

we forget that people also spend a lot of time offline. More than eight times as much, in fact. And that creates a lot more time for offline conversations. We also tend to overestimate online word of mouth because it’s easier to see.

To use an analogy, think about jokes. We all have friends who are better joke tellers than we are. Whenever they tell a joke the room bursts out laughing. But jokes also vary. Some jokes are so funny that it doesn’t matter who tells them. Everyone laughs even if the person sharing the joke isn’t all that funny. Contagious content is like that—so inherently viral that it spreads regardless of who is doing the talking.

Principle 1: Social Currency How does it make people look to talk about a product or idea?

So to get people talking we need to craft messages that help them achieve these desired impressions.

Principle 2: Triggers How do we remind people to talk about our products and ideas? Triggers are stimuli that prompt people to think about related things.

We need to design products and ideas that are frequently triggered by the environment and create new triggers by linking our products and ideas to prevalent cues in that environment.

Principle 3: Emotion When we care, we share. So how can we craft messages and ideas that make people feel something? Naturally contagious content usually evokes some sort of emotion.

Principle 4: Public Can people see when others are using our product or engaging in our desired behavior?

We need to design products and initiatives that advertise themselves and create behavioral residue that sticks around even after people have bought the product or espoused the idea.

Principle 5: Practical Value How can we craft content that seems useful? People like to help others, so if we can show them how our products or ideas will save time, improve health, or save money, they’ll spread the word.

Principle 6: Stories What broader narrative can we wrap our idea in? People don’t just share information, they tell stories.

we need to build our own Trojan horses, embedding our products and ideas in stories that people want to tell. But we need to do more than just tell a great story. We need to make virality valuable. We need to make our message so integral to the narrative that people can’t tell the story without it.

These are the six principles of contagiousness: products or ideas that contain Social Currency and are Triggered, Emotional, Public, Practically Valuable, and wrapped into Stories.

Harvard neuroscientists Jason Mitchell and Diana Tamir found that disclosing information about the self is intrinsically rewarding. In one study, Mitchell and Tamir hooked subjects up to brain scanners and asked them to share either their own opinions and attitudes (“I like snowboarding”) or the opinions and attitudes of another person (“He likes puppies”). They found that sharing personal opinions activated the same brain circuits that respond to rewards like food and money. So talking about what you did this weekend might feel just as good as taking a delicious bite of double chocolate cake.

The result? People were willing to forgo money to share their opinions. Overall, they were willing to take a 25 percent pay cut to share their thoughts. Compared with doing nothing for five seconds, people valued sharing their opinion at just under a cent.

So to get people talking, companies and organizations need to mint social currency. Give people a way to make themselves look good while promoting their products and ideas along the way. There are three ways to do that: (1) find inner remarkability; (2) leverage game mechanics; and (3) make people feel like insiders.

The key to finding inner remarkability is to think about what makes something interesting, surprising, or novel. Can the product do something no one would have thought possible (such as blend golf balls like Blendtec)? Are the consequences of the idea or issue more extreme than people ever could have imagined?

One way to generate surprise is by breaking a pattern people have come to expect.

Mysteries and controversy are also often remarkable. The Blair Witch Project is one of the most

But it’s possible to find the inner remarkability in any product or idea by thinking about what makes that thing stand out.

Experts estimate that as many as 10 trillion frequent flier miles are sitting in accounts, unused. Enough to travel to the moon and back 19.4 million times. That’s a lot of miles.

A few years ago, students at Harvard University were asked to make a seemingly straightforward choice: which would they prefer, a job where they made $50,000 a year (option A) or one where they made $100,000 a year (option B)? Seems like a no-brainer, right? Everyone should take option B. But there was one catch. In option A, the students would get paid twice as much as others, who would only get $25,000. In option B, they would get paid half as much as others, who would get $200,000. So option B would make the students more money overall, but they would be doing worse than others around them. What did the majority of people choose? Option A. They preferred to do better than others, even if it meant getting less for themselves. They chose the option that was worse in absolute terms but better in relative terms.

Jim Meehan at Please Don’t Tell addresses this problem explicitly by instructing his staff that if they need to say “no” they should try to figure out a way to say “no, but.” Such as, “No, we are all booked up at eight-thirty, unfortunately, but how about eleven?” or “No, we don’t have brand X but we have brand Y, would you like to try it?” By managing the disappointment, they maintain the allure while also maintaining customer satisfaction.

immediate word of mouth. This occurs when you pass on the details of an experience, or share new information you’ve acquired, soon after it occurs. Ongoing word of mouth, in contrast, covers the conversations you have in the weeks and months that follow. The movies you saw last month or a vacation you took last year.

As we suspected, interesting products received more immediate word of mouth than boring products.

interesting products did not sustain high levels of word-of-mouth activity over time. Interesting products didn’t get any more ongoing word of mouth than boring ones.

Sights, smells, and sounds can trigger related thoughts and ideas, making them more top of mind. A hot day might trigger thoughts about climate change. Seeing a sandy beach in a travel magazine might trigger thoughts of Corona beer.

Using a product is a strong trigger. Most people drink milk more often than grape juice, so milk is top of mind more often. But triggers can also be indirect. Seeing a jar of peanut butter not only triggers us to think about peanut butter, it also makes us think about its frequent partner, jelly. Triggers are like little environmental reminders for related concepts and ideas.

Back in mid-1997, the candy company Mars noticed an unexpected uptick in sales of its Mars bar. The company was surprised because it hadn’t changed its marketing in any way. It wasn’t spending additional money on advertising, it hadn’t changed its pricing, and it hadn’t run any special promotions. Yet sales had gone up. What had happened? NASA had happened. Specifically, NASA’s Pathfinder mission. The mission was designed to collect samples of atmosphere, climate, and soil from a nearby planet. The undertaking took years of preparation and millions of dollars in funding. When the lander finally touched down on the alien landscape, the entire world was rapt, and all news outlets featured NASA’s triumph. Pathfinder’s destination? Mars.

Take a look at the number of daily searches for “Rebecca Black” on YouTube in March 2011, soon after the song was first released. See if you notice a pattern. Searches for “Rebecca Black” on YouTube March 2011 Notice the spike once every week? Look closer and you’ll see that the spike happens on the same day every week. There was one on March 18, seven days later on March 25, and seven days later, on April 1.

One way to combat this inequality is to transform a weakness into a strength: by making a rival’s message act as a trigger for your own. A famous antismoking campaign, for example, spoofed Marlboro’s iconic ads by captioning a picture of one Marlboro cowboy talking to another with the words: “Bob, I’ve got emphysema.”

some stimuli are better triggers than others. As we discussed, one key factor is how frequently the stimulus occurs.

Frequency, however, must also be balanced with the strength of the link.

Linking a product or idea with a stimulus that is already associated with many things isn’t as effective as forging a fresher, more original link.

It is also important to pick triggers that happen near where the desired behavior is taking place.

Triggers and cues lead people to talk, choose, and use. Social currency gets people talking, but Triggers keep them talking. Top of mind means tip of tongue.

The results showed that education articles were more likely to make the Most E-Mailed list than sports articles. Health pieces were more viral than political ones.

More interesting articles were 25 percent more likely to make the Most E-Mailed list. More useful articles were 30 percent more likely to make the list.

science articles frequently chronicle innovations and discoveries that evoke a particular emotion in readers. That emotion? Awe.

More than any other emotion, awe described what many readers felt after looking at science pieces from The New York Times.

More recently, however, psychologists have argued that emotions can also be classified based on a second dimension. That of activation, or physiological arousal.

Some emotions, like anger and anxiety, are high-arousal. When we’re angry we yell at customer service representatives. When we’re anxious we check and recheck things. Positive emotions also generate arousal. Take excitement. When we feel excited we want to do something rather than sit still. The same is true for awe. When inspired by awe we can’t help wanting to tell people what happened.

Other emotions, however, have the opposite effect: they stifle action. Take sadness. Whether dealing with a tough breakup or the death of a beloved pet, sad people tend to power down. They put on some cozy clothes, curl up on the couch, and eat a bowl of ice cream. Contentment also deactivates.

HIGH AROUSAL LOW AROUSAL POSITIVE Awe Excitement Amusement (Humor) Contentment NEGATIVE Anger Anxiety Sadness

So together with the Creative Lab team, Cafaro developed a video entitled “Parisian Love.” The clip tells a budding love story, using Google searches that evolve over time. No images of people, or even voices—just the phrases entered in the search bar and the results that emerge.

In their wonderful book Made to Stick, Chip and Dan Heath talk about using the “Three Whys” to find the emotional core of an idea. Write down why you think people are doing something. Then ask “Why is this important?” three times. Each time you do this, note your answer, and you’ll notice that you drill down further and further toward uncovering not only the core of an idea, but the emotion behind it.