A GUIDE TO LOGICAL FALLACIESFallacies of DistractionYou are either with us or against us.Since you cannot prove that ghosts exist, they must exist.Appeals to Motives in Place of SupportChanging the SubjectInductive FallaciesDespite the fact that the fossil evidence repeatedly supports evolutionary theory, some are still creationists.Fallacies Involving Statistical SyllogismsAll animals evolve except humans because we are special.Causal FallaciesMissing the PointFallacies of Ambiguity”The captain was sober today.“Category ErrorsNon SequiturIf the village is violent, then it would often be at war. The village is violent, therefore it is not at war.If I am in Philadelphia, then I am in Pennsylvania. I am not Philadelphia, so I am not in Pennsylvania.Syllogistic ErrorsFallacies of ExplanationThe savagery and low intelligence of the Indian is suggested by his small cranial capacity.Fallacies of DefinitionMusic is played on a string instrument.A GUIDE TO LOGICAL FALLACIES FALLACIES OF DISTRACTION False Dilemma: two choices are given when in fact there are three options.You are either with us or against us.You either support the war on terror or you support the terrorists.From Ignorance: because something is not known to be true, it is assumed to be false.Since you cannot prove that ghosts exist, they must exist.Scientists cannot determine conclusively that global warming is occurring; therefore, it is not.Slippery Slope: a series of increasingly unacceptable consequences is drawn. Smoke pot, and eventually you will shoot heroin.If we make automatic weapons legal, eventually all weapons will be legal and society will be reduced to violent anarchy. Complex Question: Two otherwise unrelated points are conjoined and treated as a singleproposition. The reader is expected to accept or reject both together, when in reality one isacceptable while the other is not. A complex question is an illegitimate use of the “and”operator.You should support home-schooling and every American’s God-given right to raise their children as theychoose.Be a patriot: support the war in Iraq.APPEALS TO MOTIVES IN PLACE OF SUPPORT Argumentum ad baculum (appeal to force): the reader is persuaded to agree by force.If you don’t agree, I’ll kick your ass.If you want to keep your job, you will argue that the sun rotates around the Earth.Argumentum ad misercordiam (appeal to pity): The reader is persuaded to agree by sympathy.I hope you like my theory; I spent my whole life working on it.Support this policy, because it will help the Indians who are losing their land in Amazonia.Argumentum ad consequentiam (appeal to consequences): The author points to thedisagreeable consequences of holding a particular belief in order to show that this belief isfalse.You can’t agree that evolution is true; otherwise, we would be no better than monkeys.Without God, life has no meaning.Prejudicial Language: Loaded or emotive terms are used to attach value or moral goodness tobelieving the proposition.A reasonable person would agree that this policy is the best one.Only a traitorous American would vote for a Socialist candidate.1Argumentum ad Populorum (appeal to the masses): A proposition is held to be true because itis widely held to be true or is held to be true by some (usually upper crust)sector of thepopulation.Eat shit; billions of flies can’t be wrong.People everywhere are using Preparation-H® to control periodic hemorrhoidal outbreaks.CHANGING THE SUBJECT Argumentum ad hominem (attacking the person): (1) Abusive - the person’s character is attacked;You’re ugly, so your theory is wrong.(2) Circumstanial - the person’s circumstances are noted;You should discount what George Bush says about taxation because he won’t be affected by it.(3) Tu quoque - the person does not practice what is preached.You say I should stop drinking but you drink like a fish.Argumentum ad vericundiam (appeal to authority): While sometimes it may be appropriate to cite an authority to support a point, often it is not. Inparticular, an appeal to authority is inappropriate if:(1) the person is not qualified to have an expert opinion on the subject,(2) experts in the field disagree on this issue,(3) the authority was making a joke, drunk, or otherwise not being serious.A variation of the fallacious appeal to authority is hearsay. An argument from hearsay is anargument which depends on second or third hand sources. ”You better listen to him; he’s pre-med.“Noted physician Bill Smith recommends that you place your money in diversified stock portfolios.Anthropologist Steven Alsburry has proven that female circumcision is a human rights violation.A visibly intoxicated Fed Chair Alan Greenspan slurred that the economy is “in the toilet and will never fullyrecover.“I heard that if an article is not listed in the syllabus, then I am not required to read it.Anonymous Authority: The authority in question is not named. This is a type of appeal toauthority because when an authority is not named it is impossible to confirm that theauthority is an expert. However the fallacy is so common it deserves special mention. Avariation on this fallacy is the appeal to rumor. Because the source of a rumor is typically notknown, it is not possible to determine whether to believe the rumor. Very often false andharmful rumors are deliberately started in order to discredit an opponent.An unnamed White House source has confirmed that taxes will be raised this quarter.I hear he drinks rather heavily.Style Over Substance: The manner in which an argument (or arguer) is presented is felt toaffect the truth of the conclusion.Beautiful people love this class, so it must be good.He really worked the crowd into a frenzy; everything he said must be true.2INDUCTIVE FALLACIES Hasty Generalization: The sample is too small to support an inductive generalization about apopulation.A Frenchman stole my wallet; all Frenchmen are thieves.All of my friends like Miller Lite, so everyone will like it.Unrepresentative Sample: The sample is unrepresentative of the sample as a whole.To determine the economic strategies of street kids worldwide, I interviewed 100 of them in Haiti.The strawberries on top of the box look ripe, so they all must be. False Analogy: In an analogy, two objects (or