Emotion: When we share, we care (Contagious, part 3)

I’m in the middle of a writing few posts about Jonah Berger’s book Contagious: Why things catch on. Berger describes six reasons that products, ideas, and behaviors spread. Here is #3.

Emotion: when we care, we share

Do you remember when a dumpy middle-aged woman took the stage on the TV show Britain’s Got Talent? The judges smirked—until she opened her mouth and sang “I Dreamed a Dream”–in a voice that made people’s jaws drop.

I’m guessing you didn’t watch Susan Boyle sing on TV (especially since it’s a British show). You saw it because someone sent you the link. More than 14 million people have watched Susan sing that song on YouTube.

People share things that affect them emotionally. Susan Boyle touches us because she was acting out her own dream–and overcoming people’s assumptions in the process.

A similar instinct leads to people sharing photos of adorable babies, cute kittens and dramatic sunsets. Arousing people’s emotions is one way to spread the word about your idea or product.

Jonah Berger says that physical arousal also leads to sharing. In an experiment, students were asked to sit still or to jog for about a minute. As expected, jogging increases arousal. Then the students were shown a neutral online new article and told they could email it to anyone. The experiment showed that the students who jogged in place were more likely to share.

Negative emotions, such as anger and anxiety, also lead us to talk to others (in person or online), spreading the word about a negative experience. On the other hand, people are less likely to share things that make them sad.

Berger has an interesting table in Contagious. High-arousal emotions are more likely to encourage people to share information than low-arousal emotions.

High arousal Low arousal
Positive Awe
Amusement (humor)
Negative Anger


Here are the six 6 principles of contagiousness from Jonah Berger.

  1. Social currency
  2. Triggers
  3. Emotion
  4. Public
  5. Practical value
  6. Stories

Read about step 1 (Social currency) here and step 2 (Triggers) here. And stay tuned for blog posts about the other three steps.