en-us 2009 A weblog for the Fallacy Files website. http://www.fallacyfiles.org The Agency for Counter-Terrorism (ACT) comes to you with a logical problem. The agency has information on four subjects, one of whom is known to be a terrorist. To protect the innocent, we will refer to them as Subjects 1 through 4. Subject 1 is the known terrorist. Subject 1 is acquainted with Subject 2. Subject 2 has met Subject 3, therefore they are acquainted. Subject 3 was observed talking to Subject 4, so they're also acquainted. Subject 4 is known not to be a terrorist. It's not known whether Subjects 3 and 4 are terrorists or not. ACT wants to know: among the four subjects, is a terrorist acquainted with a non-terrorist?... http://www.fallacyfiles.org/archive112009.html#11152009 Test yourself with an article in the latest issue of "Scientific American Mind" on the difference between intelligence and rationality by psychologist Keith Stanovich. It contains a number of puzzles that may make you feel foolish, but don't feel too bad if you get a wrong answer: you're in good company. Regular readers of "The Fallacy Files" should recognize the Wason selection task and a puzzle based on the base rate fallacy, and I hope would not be fooled by them... http://www.fallacyfiles.org/archive112009.html#11112009 Continuing the twin themes of "where's the harm?" and weird science, here's a couple of new books: Chris Mooney and Sheril Kirshenbaum's "Unscientific America" and Michael Specter's "Denialism". Both appear to deal with the widespread scientific illiteracy that helps lead to the harm that I've noted in previous entries. For instance, the quantum quackery practiced by James Arthur Ray is made possible by the fact that so many people have no idea what quantum mechanics is all about, and can't tell the difference between the real thing and bafflegab. You don't have to be a physicist to be able to tell that Rhonda Byrne doesn't know what she's talking about; you just need to be scientifically literate. I haven't done a book club in a long time, and it's possible that one or both of these books might make good material. As always, it would be nice if someone would send me review copies. http://www.fallacyfiles.org/archive112009.html#11082009 Here it is... http://www.fallacyfiles.org/archive112009.html#11062009 The Multiple Comparisons Fallacy. I haven't added it to the Taxonomy yet; that is to come.... http://www.fallacyfiles.org/archive112009.html#11012009 Britain's "Guardian" newspaper has a fascinating history of the birth and growth over the last ten years of the estimate of the number of prostitutes trafficked into the U.K.... http://www.fallacyfiles.org/archive102009.html#10282009 Ben Goldacre's latest "Bad Science" column deals with a slanted debate about a slanted movie... http://www.fallacyfiles.org/archive102009.html#10252009 I've been hearing this sort of argument made recently by right-wing pundits: Obama is a good speaker. Hitler is a good speaker. [More or less implied conclusion:] Obama is Hitler (or like Hitler).... http://www.fallacyfiles.org/archive102009.html#10242009 David B. Grant's "Joseph Spider and the Fallacy Farm". http://www.fallacyfiles.org/archive102009.html#10212009 I heard about the following incident when it happened over a week ago, but I didn't realize who organized it until today... http://www.fallacyfiles.org/archive102009.html#10192009 The only clue the police have to a murder is a blurry photograph on a cell phone camera. They question a woman who might be able to identify the killer in the picture: "Who is this man, Mrs. Murphy?" There was a long pause as the woman looked intently at the photo. Finally, she answered: "This man's son is my daughter's father's son". After that, she refused to answer any further questions. For the third time, the police come to you for help: If the witness spoke truly, who is the murderer? http://www.fallacyfiles.org/archive102009.html#10122009 Here's another "Volokh Conspiracy" item: Eugene Volokh has an extensive criticism of a study purporting to show that carrying a gun does not afford protection against being shot. In fact, the study claims that people carrying guns are more likely to be shot than those unarmed. I haven't had an opportunity to read the study itself, so I can't confirm Volokh's criticisms, but they certainly sound plausible. The best that such a study can show is a correlation, rather than a causal relationship, between carrying a gun and being shot; or the lack of a correlation, rather than the lack of a causal relationship, between carrying and not being shot. It's plausible that people who carry guns do so because they are more likely to be shot at than those who don't carry, so it's possible that guns offer them protection even though they are shot at a higher rate than those who aren't packing. http://www.fallacyfiles.org/archive102009.html#10062009 Law professor David Post of "The Volokh Conspiracy" has a post about the interpretation of sections 116 and 256 of the Patent Act, which are almost identical except for a single comma... http://www.fallacyfiles.org/archive102009.html#10042009 Poll: Support for Obamacare at New Low... http://www.fallacyfiles.org/archive092009.html#09302009