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Dewey's Law of No Fun

In general, students should be wary of "fun ideas." I call this Dewey's Law of No Fun. If an idea is fun to believe, it is probably not true.

Why? Because a fun idea tends to be propagated even if it is false. The main factor determining whether an idea is propagated (spread around) is whether people enjoy passing it on.

If people enjoy passing something on, then it becomes like a contagion, spreading quickly. This metaphor is also implied by the word viral applied to social media content, of course.

Truth value is almost irrelevant to the propagation of an idea. Fun value is very predictive of propagation.

What is Dewey's Law of No Fun?

Please note: I am not saying it is bad to believe in enjoyable things. This book is full of ideas that I think are both enjoyable and true.

What I am saying is that when you try to explain why an idea is spread or propagated, the truth value of the idea is not the only factor. In fact, it might not be as big a factor as how much fun it is to spread around.

Certain catchy ideas have an amazing shelf life. Everybody propagates the original fun idea, not the refutation. The result is what some observers call zombie lies, false facts that come back from the dead, passed around even after being debunked by experts.

An example is the claim that messages quickly flashed on a movie screen can influence viewers (long ago revealed to be a hoax). Another is the claim that "90% of the brain is unused."

Another is that subliminal learning can take place during sleep. Another is that people can learn to comprehend fully while speedreading. These claims have all been debunked, but they persist, because they are fun to believe.

What are examples hoaxes or myths which endure?

Outside of psychology, a remarkable example of a zombie lie is the idea that crop circles–patterns found stamped into farmers' fields–are caused by UFOs. One can use any search engine to see how the fun idea has been spread around.

A web search for "crop circles" yields dozens of web sites that accept the idea of crop circles created by extraterrestrial aliens. It is a fun idea, despite the fact that the original crop circle hoaxers long ago confessed what they had done and how they did it

They even put up their own web site explaining their techniques ( To their credit, they do not claim any assistance from aliens.

Urban Legends

Virally propagated memes were common even before the internet. Author Jan Harold Brunvand introduced the concept of urban legends in the book The Vanishing Hitchhiker: American Urban Legends & Their Meanings (1989).

Urban legends are fun stories passed around so frequently that lots of people know of them. People may believe urban legends are true until they see the legend discussed in one of Brunvand's amusing books or a skeptical web site.

The web site does a great job of debunking urban legends and fake news of all kinds. It also reports on stories that are documented as true (such as the story of Larry Walters, who fastened surplus weather balloons to lawn furniture and soared to 16,000 feet).

What is an "urban legend"?

Urban legends tend to have a bizarre or shocking element to them, which probably helps to insure that the story gets passed around. A classic example involves a fellow who wakes up in a bathtub, after a hard night of partying, and finds a scar on his stomach. A note informs him that one of his kidneys has been removed.

People often swear an urban legend is true, because (they claim) the experience actually happened to somebody close to them...not a close personal friend, or anybody they can name, but a "friend of a friend." This is such a common statement that Brunvand coined an acronym, FOAF, which stands for "friend of a friend."

What is a FOAF?

Apparently a FOAF is close enough to have credibility, while distant enough that nobody can find out who it is. So a FOAF is a perfect authority to cite when trying to prove that a fictitious urban legend is true.

In psychology, we do not have FOAFs presented as credible sources, but we do have legends. Introductory textbooks have been blamed for propagating simplistic and misleading versions of classic findings.

Fortunately, anybody who has access to the internet can determine whether a claim is backed up by good evidence. Google Scholar (https://scholar.­ is one of the best resources for this.

Google Scholar works much like the regular Google search engine but specializes in cataloging scholarly books and journals. It can be used by anybody to locate scholarly literature on any topic.

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