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Carl Sagan's
Baloney Detection Kit

Based on his book "The Demon Haunted World: Science as a candle in the dark"   Muses on the current state of scientific thought, which offers him marvelous opportunities to entertain us with his own childhood experiences, the newspaper morgues, UFO stories, and the assorted flotsam and jetsam of pseudoscience. Along the way he debunks alien abduction, faith-healing, and channeling; refutes the arguments that science destroys spirituality, and provides a 'baloney detection kit' for thinking through political, social, religious, and other issues."

The following are suggested as tools for testing arguments and detecting fallacious or fraudulent arguments:

  • Wherever possible there must be independent confirmation of the facts

  • Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.

  • Arguments from authority carry little weight (in science there are no "authorities").

  • Spin more than one hypothesis - don't simply run with the first idea that caught your fancy.

  • Try not to get overly attached to a hypothesis just because it's yours.

  • Quantify, wherever possible.

  • If there is a chain of argument every link in the chain must work.

  • "Occam's razor" - if there are two hypothesis that explain the data equally well choose the simpler.

  • Ask whether the hypothesis can, at least in principle, be falsified (shown to be false by some unambiguous test). In other words, it is testable? Can others duplicate the experiment and get the same result?

Additional issues are

  • Conduct control experiments - especially "double blind" experiments where the person taking measurements is not aware of the test and control subjects.

  • Check for confounding factors - separate the variables.

Common fallacies of logic and rhetoric

  • Ad hominem - attacking the arguer and not the argument.

  • Argument from "authority".

  • Argument from adverse consequences (putting pressure on the decision maker by pointing out dire consequences of an "unfavourable" decision).

  • Appeal to ignorance (absence of evidence is not evidence of absence).

  • Special pleading (typically referring to god's will).

  • Begging the question (assuming an answer in the way the question is phrased).

  • Observational selection (counting the hits and forgetting the misses).

  • Statistics of small numbers (such as drawing conclusions from inadequate sample sizes).

  • Misunderstanding the nature of statistics (President Eisenhower expressing astonishment and alarm on discovering that fully half of all Americans have below average intelligence!)

  • Inconsistency (e.g. military expenditures based on worst case scenarios but scientific projections on environmental dangers thriftily ignored because they are not "proved").

  • Non sequitur - "it does not follow" - the logic falls down.

  • Post hoc, ergo propter hoc - "it happened after so it was caused by" - confusion of cause and effect.

  • Meaningless question ("what happens when an irresistible force meets an immovable object?).

  • Excluded middle - considering only the two extremes in a range of possibilities (making the "other side" look worse than it really is).

  • Short-term v. long-term - a subset of excluded middle ("why pursue fundamental science when we have so huge a budget deficit?").

  • Slippery slope - a subset of excluded middle - unwarranted extrapolation of the effects (give an inch and they will take a mile).

  • Confusion of correlation and causation.

  • Straw man - caricaturing (or stereotyping) a position to make it easier to attack..

  • Suppressed evidence or half-truths.

  • Weasel words - for example, use of euphemisms for war such as "police action" to get around limitations on Presidential powers. "An important art of politicians is to find new names for institutions which under old names have become odious to the public"

Carl Sagan on Kindle!

Shadows of Forgotten Ancestors:
A Search for Who We Are

"Dazzling...a feast. Absorbing and elegantly written, it tells of the origins of life on earth, describes its variety and character, and culminates in a discussion of human nature and the complex traces of humankind's evolutionary is an amazing story masterfully told."


Dragons of Eden

"Dr. Carl Sagan takes us on a great reading adventure, offering his vivid and startling insight into the brain of man and beast, the origin of human intelligence, the function of our most haunting legends--and their amazing links to recent discoveries. A history of the human brain from the big bang, fifteen billion years ago, to the day before yesterday...It's a delight."


"The best-selling science book ever published in the England language, Cosmos is a magnificent overview of the past, present, and future of science.  Brilliant and provocative, it traces today's knowledge and scientific methods to their historical roots, blending science and philosophy in a wholly energetic and irresistible way. A companion volume to a popular television series and seventy-week New York Times bestseller places fifteen billion years of evolution in an accessible format." 



Billions & Billions:
Thoughts on Life and Death at the Brink of the Millennium

"Carl Sagan's last work seems to be the most powerful yet. He takes an unabashed look at virtually every aspect of human existence and its impact on the home planet. It a philosophical work that transcends the paradigms of the past, dropping the excuses for excess such as  patriotism, progress, and religion."



The Astonishing
The Scientific
Search for
the Soul

Francis Crick
Godel, Escher, Bach:
An Eternal Golden Braid

Douglas R. Hofstadter
Guns, Germs,
and Steel:
The Fates of
Human Societies

Jared Diamond
The Life
of the Cosmos

by Lee Smolin

Hold on to your hats!
 A professor at the   Center
 for Gravitational   Physics
 and Geometry is about to
take you on...
  the ride of your life!

~ Pick up a copy for a friend! ~



The Amazing Randi
Richard Dawkins
(Las Vegas Nevada - 2005, 2006)


Atlas Shrugged, by Ayn Rand

"The Only Book Available That Will Arm You To Fight Nonsense! Do you ever listen to people discuss mystical things with reverie and wonder why they believe all that crap? Do you ever wonder what belief in all things irrational ultimately does to the world? Here is your chance to find out. Atlas Shrugged is the most important book ever written, and will provide you with all the tools necessary to understand how to live a life of reason and see the law of cause and effect in action when man tries to live with out his most important tool, his mind."

Further resources:

Less serious sites:


The Selfish Gene, by Richard Dawkins

"Inheriting the mantle of revolutionary biologist from Darwin, Watson, and Crick, Richard Dawkins forced an enormous change in the way we see ourselves and the world with the publication of The Selfish Gene. Suppose, instead of thinking about organisms using genes to reproduce themselves, as we had since Mendel's work was rediscovered, we turn it around and imagine that 'our' genes build and maintain us in order to make more genes. That simple reversal seems to answer many puzzlers which had stumped scientists for years, and we haven't thought of evolution in the same way since."


The Blind Watchmaker:
Why the Evidence of Evolution Reveals a Universe Without Design, by
Richard Dawkins

"Patiently and lucidly, this Los Angeles Times Book Award and Royal Society of Literature Heinemann Prize winner identifies the aspects of the theory of evolution that people find hard to believe and removes the barriers to credibility one by one. As readable and vigorous a defense of Darwinism as has been published since 1859. A vigorous and readable defense of Darwinism which leaps effortlessly from the primeval soup to long rows of taxonomy. Deep enough to be valuable to biologists, yet simple and well-written so as to appeal to a mass audience."

Mormonism, one of the world’s fastest growing religions. But unless you were raised a Mormon...


 Still more books           The 101 Book Atheism Library !              Science Library

Parts of this page Prepared by Michael Paine; 1998.    Parts of this page were taken from