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

The "Quack Science" Syndrome

Some people are so certain of their ideas that they have no tolerance for criticism, or they grow impatient with the cautious and skeptical approach of science. They may wish to claim that they have "proven" something without offering any replicable evidence. When people falsely claim that evidence exists for a phenomenon, this is called pseudo-science , quack science , or hack science. Fortunately, quack science is easily recognized. The distinctive features might be called the Quack Science Syndrome.

Extravagant claims

What is a "red flag" which indicates quack science?

One "red flag" or warning sign which points to quack science is a simply a claim that sounds too good to be true. In judging extravagant scientific claims, one must adopt the same skeptical attitude one might adopt when receiving a letter that announces in large type YOU HAVE WON A MILLION DOLLARS (then the small type says "if your number is chosen"). In general, as many mothers and fathers have told their children, if something sounds too good to be true, it probably is. People do win lotteries occasionally, and sometimes there are big breakthroughs in science. But, more commonly, a finding advertised as a "dramatic scientific breakthrough" is worth about as much an e-mail promising to share a million dollars if you help get the money out of Nigeria.

Examples of claims that sound too good to be true (as of this writing) include the following:

—unlimited cheap power (perpetual motion machines, special gas formulations that make cars go 200 miles per gallon, cold fusion)

—dramatic medical cures discovered by isolated doctors or obscure medical clinics (cures for cancer, obesity, arthritis)

—life extension (live 100 years without looking like it)

Extravagant claims in the realm of psychology include the following:

—therapies which are cheap, quick, and superior to every other therapy (for almost every problem and almost every person)

—claims about psychic powers (plants that respond to thoughts and emotions, thoughts transferred from one person to another, communication with spirits)

—techniques for boosting your IQ, giving you unlimited memory, educating your subconscious mind, or super-learning (speedreading courses, subliminal learning tapes)

What did Sagan offer as a rule of thumb, regarding extraordinary claims?

A good rule of thumb often attributed to Carl Sagan is that extraordinary claims require extraordinary evidence. A person who claims to communicate with plants through psychic energy is making a very extraordinary claim. Such a person should have powerful evidence for the phenomenon before making the claim, because it contradicts all the current scientific knowledge about plants. Most "quack science" claims are backed by very weak evidence, usually a single experiment or two that could easily be wrong or faked.

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Copyright © 2007-2011 Russ Dewey