This is the 2007 version. Click here for the 2017 chapter 01 table of contents.

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 probably is not true. Why? Because a fun idea can spread easily without being true. Its propagation (its spread as a rumor or myth) can be explained by how fun it is to pass along. That explains why you hear about it. Truth value is almost irrelevant to the propagation of an idea, but "fun value" is very predictive of propagation.

What is Dewey's Law of No Fun?

Please note that 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 ,truth value is probably not as powerful a factor as how much "fun" it is to spread the idea around.

What are examples hoaxes or myths which endure?

Certain catchy ideas have an amazing shelf life...everybody propagates the original fun idea, not the refutation. Examples are the idea that messages quickly flashed on a movie screen can influence viewers (long ago revealed to be a hoax) or the example used earlier in this chapter: "90% of the brain is unused" or the belief that crop circles—patterns found stamped into farmers' fields—are caused by UFOs.

The crop circle example is handy because you can use any search engine to verify how the fun idea has been spread around. If you look for "crop circles" you will find dozens of web sites that accept the idea of crop circles created by extraterrestrial aliens, despite the fact that the original perpetrators of the hoax have their own web site explaining their techniques (<>). For a list of many "strange hoaxes that endure" see this web site:


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Copyright © 2007-2011 Russ Dewey