Test the Curse of Knowledge With Tappers and Listeners

Take a song like "The Star-Spangled Banner" and tap out the rhythm to a friend on a table. Ask your friend to listen and guess the name of the song. Do you think your friend will guess right?

A 1990 study on this experiment showed that listeners guessed only 2.5 percent of the songs (3 out of 120 attempted). Before the listeners guessed the song, the tappers were asked to predict if the listeners would guess correctly. They predicted that the odds were 50 percent! Why the discrepancy? When a tapper taps, she is hearing the song in her head, but the listener can't. The problem is that the tapper has been given knowledge (the song title) that makes it impossible for her to imagine what it's like to lack that knowledge. This is the Curse of Knowledge. Once we know something, we find it hard to imagine what it was like not to know it.

The tapper/listener experiment is reenacted every day across the world between CEOs and frontline employees, teachers and students, politicians and voters, marketers and customers, writers and readers. All of these groups rely on ongoing communication, but, like the tappers and listeners, they suffer from enormous information imbalances. You can quash the Curse of Knowledge with the six principles of stickiness.

The Simplicity Test

Spend ten to fifteen seconds, no more, studying the letters below. Then write down as many letters as you can remember.


If you're like most people, you probably remembered about seven to ten letters. That's not much information. Compactness is essential because there's a limit to the amount of information we can juggle at once.

Now try the exercise again. The letters are the same but are grouped differently. Once again, study the letters for ten to fifteen seconds, then close the book and test your recall.


Chances are you did much better the second time. Suddenly the letters meant something, which made them easier to remember. In Round 1 you were trying to remember raw data. In Round 2, you were remembering concepts: John F. Kennedy, the FBI, the North Atlantic Treaty Organization, UPS, NASA, the IRS.

The Concreteness Test

1) Think of five silly things that people have done in the world in the past ten years.
2) Next, think of five silly things your child has done in the past ten years.

Most people can think of about the same number of things for each exercise–even though your child's actions are a tiny fraction of the world! Why? Because concreteness focuses your brain.

The Velcro Theory of Memory Test

Read each sentence below slowly. As you move from one sentence to another, you'll notice that it feels different to remember different kinds of things.

Remember the capital of Kansas
Remember the first line of the song "Hey Jude"
Remember the Mona Lisa
Remember the house where you spent most of your childhood
Remember the definition of "truth"
Remember the definition of "watermelon"

Each command to remember seems to trigger a different mental activity. Memory, then, is not like a single filing cabinet. It is more like Velcro. If you look at Velcro up close, you'll notice that one side has lots of tiny hooks and the other has lots of tiny loops. When you press the two sides together, a huge number of hooks get snagged inside the loops, and that's what causes Velcro to seal. Similarly, your brain hosts a staggering number of loops. The more "hooks" we can put into our ideas, the easier it will be for people to remember.

The Choice Paralysis Test

A group of students were given the following choice of how to spend one evening:

1. Attend a lecture by an author you admire who is visiting just for the evening, or
2. Go the library and study?

21 percent decided to study. Suppose instead they had been given three choices:

1. Attend the lecture by an author you admire who is visiting just for the evening.
2. Go to the library and study.
3. Watch a film that you've been wanting to see.

Do you think they answered differently? Remarkably, when a different group of students were given the three choices, 40 percent decided to study -- double the number who did before. Giving students two good alternatives to studying, rather than one, paradoxically makes them less likely to choose either. This behavior isn't "rational," but it is human. A consistent finding in the psychology literature is that too many choices can be paralyzing. If your ideas help people prioritize among options, you can rescue them from the quicksand of decision paralysis. That's why finding the core of your idea is so valuable.

Copyright © 2009 Chip and Dan Heath co-authors of Made to Stick: Why Some Ideas Survive and Others Die

Author's Bio: 

Chip Heath, co-author of Made to Stick: Why Some Ideas Survive and Others Die, is a professor of organizational behavior in the Graduate School of Business at Stanford University. He lives in Los Gatos, California.

Dan Heath, co-author of Made to Stick: Why Some Ideas Survive and Others Die, is a Consultant to the Policy Programs of the Aspen Institute. A former researcher at Harvard Business School, he is a co-founder of Thinkwell, an innovative new-media textbook company. He lives in Raleigh, North Carolina.

Please visit madetostick.com.