A Collection of Strange Beliefs, Amusing Deceptions, and Dangerous Delusions

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From Abracadabra to Zombies - 768 entries | View All

The Skeptic's Dictionary features definitions, arguments, and essays on hundreds of strange beliefs, amusing deceptions, and dangerous delusions. It also features dozens of entries on logical fallacies, cognitive biases, perception, science, and philosophy.


Sample the Skeptic's Dictionary

perfect solution fallacy (nirvana fallacy)

The perfect solution fallacy (aka the nirvana fallacy) is a fallacy of assumption: if an action is not a perfect solution to a problem, it is not worth taking. Stated baldly, the assumption is obviously false. The fallacy is usually stated more subtly, however. For example, arguers against specific vaccines, such as the flu vaccine, or vaccines in general often emphasize the imperfect nature of vaccines as a good reason for not getting vaccinated: vaccines aren't 100% effective or 100% safe. Vaccines are safe and effective; however, they are not 100% safe and effective. It is true that getting vaccinated is not a 100% guarantee against a disease, but it is not valid to infer from that fact that nobody should get vaccinated until every vaccine everywhere prevents anybody anywhere from getting any disease the vaccines are designed to protect us from without harming anyone anywhere.>>more

sample Mysteries and Science (for kids 9 and up)


In a nutshell: Some natural things are good, but so are some unnatural things, like vaccines. Some natural things are harmful, like poisonous mushrooms. Knowing that something is natural doesn't tell you anything about whether it's good or bad for you.

Many people think that if something is natural it must be good. They might try to have you take a medicine because it's natural. They might even try to get you to not take a medicine because it'snot natural. Just remember that some natural things are poisonous, so if a medicine is good for you it isn't good because it's natural. It's good because it does something to make you better. Also, if a medicine is bad for you, it isn't because it's not natural. It's because it does something that makes you worse off.>>more

a blast from the past

What if Gary Schwartz is right? 

by Robert Todd Carroll 

Gary Schwartz, author of The Afterlife Experiments: Breakthrough Scientific Evidence of Life After Death (Atria 2003), has collected “extraordinary data in many experiments over many years” that support the hypothesis that consciousness is independent of the brain and survives the death of the brain (268). That the spirit survives the death of the body is something that many people on our planet already believe, so it is not clear exactly what impact this data will have on the billions of people who already strongly believe in immortality or reincarnation. True, most people come to such beliefs by being taught them from birth onward and by growing up in communities where such beliefs are constantly reinforced. Many of these people also have anecdotal evidence to support their belief. But Schwartz thinks his scientific data might have an enormous impact. Presumably, one impact would be that even skeptics would come to accept what he calls “the living soul hypothesis.”>> more

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