Anecdotal evidence

An anecdote is generally a brief story, often (auto)biographical, that illustrates a particular aspect of a situation. An example is the story of George Washington and the cherry tree.

In the world of pseudoscience, an anecdote is the equivalent of a peer reviewed, double blind, repeatable scientific experiment with consistent results. In other words the true believers accept that just because something once seemed to work for someone -- "Billy-Bob ate 3 pounds of apples a day for a year and his cancer disappeared" -- then it will work for everyone, everywhere, every time.

This sort of thing is termed anecdotal evidence and is usually the starting point of a proper scientific investigation, whereas it is all too often the ending point of a pseudoscientific investigation. The use of anecdotal evidence to draw a conclusion is the same thing as drawing a conclusion from a sample size of 1. Try that in an introductory statistics class and you will be rewarded with a big fat F.

An example of anecdotal evidence comes from Andrew Schlafly's essay, "Do Liberal Teachings Cause Mental Illness?" an argument so daft and anti-intellectual that it doesn't even amount to pseudoscience, in which he cites actor Stephen Fry as a famous example of a person with liberal values who suffers a mental illness. When other editors pointed out that bipolar disorder, Fry's condition, is largely hereditary, this information was added to the article, but the example still remains in the essay as "anecdotal evidence" for this bizarre argument. Naturally Andrew Schlafly himself isn't suffering from any mental illness and neither is any other Conservative Republican. George W Bush's irrational and disastrous foreign policies are not due to any phychiatric condition.

Anecdotal evidence may also refer to the non-scientific process of fabricating statistics on the basis of anecdotal observation. Andrew Schlafly is kind enough to provide an example of this kind of anecdotal evidence in his essay [CP:Mystery:Why Do Non-Conservatives Exist?|Why Do Non-Conservatives Exist?]]. The first two sections are composed entirely of so-called "statistics" generated exclusively on the basis of anecdotal data, a fact which Schlafly admits on the talk page. He claims that the statistics are based on his own observations, apparently having decided that cognitive bias does not apply to him. He further states that the estimates are also based on "available articles;" however, only two of the statistics are accompanied by citations, and both of the citations refer to singular anecdotes. Ironically, the article cites close-mindedness as a liberal trait in spite of the fact that the entire essay is essentially one large ad hominem attack. Indeed, the essay offers not a shred of refutation of any liberal positions, except for the fallacious over-generalization that they are irrational, arrogant, etc. Because of the obvious irony implicit in the essay, there exists a dispute as to whether Schlafly was engaging in an attempt at self-deprecating humor in the form of parody.

Anecdotal evidence is often used in politics, journalism, blogs and many other contexts to make or imply generalizations based on very limited and cherry-picked examples, rather than reliable statistical studies. A classic instance was Ronald Reagan's story of a "welfare queen" who was abusing the system, which Reagan attempted to portray as indicative of the average welfare recipient.

Remember: the plural of "anecdote" is NOT "data."

See also

• Magical thinking
• Credulity
• Gullibility
• Miracle