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1. Formal Fallacies & Fallacies of Language

2. Rhetorical Devices Techniques for generating emotional or psychological, rather than rational, responses from an audience. Some people may believe that Paul is dishonest, but I’ll withhold my judgment and allow Paul to prove he’s an honest guy. EuphemismDysphemismWeaslerDownplayerStereotypeInnuendoLoaded QuestionRidiculeSarcasmHyperboleProof Surrogate
3. Fallacies of Relevance Argument by ForceArgument from PityApple PolishingGroupthinkTwo Wrongs Make Right Faulty Appeal to AuthorityFaulty Appeal to Popularity/Common BeliefFaulty Appeal to Common PracticeFaulty Appeal to TraditionBandwagon Fallacy I can’t believe you’re so dumb that you accept the arguments of anti-gun rights fascists. Their current proposal to control gun sales at gun shows is just the kind of law Hitler would have loved, and I don’t know about you, but I want nothing to do with any effort to strip hard working Americans of their constitutional right to bear arms. No one will ever be able to eliminate crimes committed with guns, so if the choice is between allowing Americans to have full rights or to make them live in a fascist state, I choose the former. An idea or line of reasoning is offered in support of a claim that does not bear on the truth-value of the claim. Ad HominemPoisoning the WellGuilt by AssociationGenetic FallacyStraw ManFalse DilemmaPerfectionist FallacyLine-Drawing FallacyMisplacing the Burden of ProofAppeal to IgnoranceEmotional AppealArgument from OutrageScapegoatingWishful ThinkingScare Tactics
4. Fallacies of Induction Hasty GeneralizationFallacy of the Lonely FactArgument by AnecdoteFallacy of Small SampleGeneralizing from Exceptional CasesFallacy of the Biased SampleSelf-Selection FallacyFallacy of AccidentFalse/Weak Analogy Supporting general statements with inadequate/weak reasoning OR faultily applying general statements to specific cases. Look, you can say Johnston is a good teacher all you want, but I read a dozen student comments about him on ratemyprofessor.com, and it seems like students last semester thought he was aloof and unavailable—and I don’t care that he was dealing with health issues that semester. My sister told me of a time she spoke with him a few semesters ago, and he sounds like a jerk. I think you have to take seriously the choice of instructor you sign up for, so you shouldn’t sign up with someone who’s got negative feedback on ratemyprofessor.com.
5. Fallacies of Cause and Effect Post Hoc, Ergo Propter HocOverlooking the Possibility of CoincidenceOverlooking a Possible Common CauseOverlooking the Possibility of Random VariationOverlooking the Possibility of RegressionCum Hoc, Ergo Propter HocSlippery SlopeUntestable Explanation Failing to establish the basis for a claim that one event is the trigger for another event. As I was driving in to school today, I had to pull over because I had a massive allergy attack. When I started going again, I came across a horrible accident at the next intersection that had just happened. That wouldn’t been me! I guess God was really looking out for me by triggering that allergy attack.
6. Fallacies of Form Affirming the ConsequentDenying the AntecedentUndistributed MiddleEquivocationAmphibolyFallacy of CompositionFallacy of DivisionConfusing Explanations with ExcusesContradictories & ContrariesConsistency & InconsistencyMiscalculating ProbabilitiesGambler's FallacyOverlooking Prior ProbabilitiesOverlooking False Positives Putting together the terms of an argument in a manner that violates one or more rules of logic. If it is legal for Sally to drink, then she is 21 or older. It is not, though, legal for Sally to drink, so she is not 21 or older. If X, then Y. Not X. Therefore, not Y. Denying the Antecedent creates an invalid argument.
7. Professor Parker can tell you if you are sick; after all he is a doctor. The laws imply lawgivers. There are laws in nature. Therefore there must be a cosmic lawgiver. A warm beer is better than a cold beer. After all, nothing is better than a cold beer, and a warm beer is better than nothing. Fallacy of Equivocation: When a key term of an argument is used ambiguously, with one meaning being employed in one part of the argument and another meaning being employed in another part of the argument.
8. 7. A dialogue: JILL: Helen has her mother’s eyes. BILL: Good lord! Can the woman still see? 23. Child molesters are inhuman. So I think it’s perfectly acceptable to punish them any way we want because they are not really human. Sure philosophy helps you argue better, but do we really need to encourage people to argue? There's enough hostility in this world. I don't see how you can say you're an ethical person. It's so hard to get you to do anything; your work ethic is so bad
9. 2. If this man is the president, then he believes in immigration reform. If this man is vice president, then he believes in immigration reform. Therefore, if this man is president, then he is vice president. All lions are animals. All cats are animals. Therefore, all lions are cats. Undistributed Middle If X, then Y. If Z, thenY. Therefore, if X, then Z. All X are Y. All Z are Y. Therefore, all X are Z. X (subject term of the conclusion) is the “minor term.” Z (predicate term of the conclusion) is the “major term.” Y (doesn’t appear in conclusion) is the “middle term.” To be “distributed,” the middle term must refer at least once to the class as a whole. If X, then Y. If Y, then Z. Therefore, if X, then Z. All X are Y. All Y are Z. Therefore, all X are Z.
10. 15. Anybody who is serious about losing weight will go on a low-carb diet. Since Jerry is now on such a diet, that tells me he is serious about losing weight. All X are Y. Z is Y. Therefore, Z is X. X=People serious about losing weight. Y=People on low-carb diet. Z=Jerry Can you develop an argument with these terms that is valid? All X are Y. Z is X. Therefore, Z is Y.
11. 25. All the hotels in the Southwest chain are known for their elaborate lobbies and spectacular lobby bars. The Arlington has a fantastic lobby and a great lobby bar, which makes me believe it’s a Southwest Hotel. Translate with X, Y, & Z. X=Hotels in the Southwest chain. Y=Hotels with elaborate lobbies and elaborate lobby bars. Z=Arlington. All X are Y. Z is Y. Therefore, Z is X.
12. 3. If global warming is for real, then the mean global temperature will have risen over the past ten years. And that is what has happened. Therefore, global warming is for real. Invalid Argument: Affirming the Consequent If X, then Y. Y. Therefore, X. X=Global warming is for real. Y=The mean global temp will have risen over the past ten years. Valid Argument=Affirming the Antecedent If X, then Y. X. Therefore, Y.
13. 9. If Congress changes marijuana from a Class 1 drug to something lesser, next year the penalties for possession will be much less than they are now. But Congress is not going to declassify marijuana anytime soon. So we’ll have to live with the drastic penalties for at least another year. Invalid Argument: Denying the Antecedent If X, then Y. Not X. Therefore, not Y. X=? Y=? Valid Argument: Denying the Consequent If X, then Y. Not X. Therefore, not Y.
14. 10. If you are rich, then your car is something like a Mercedes or a Bentley. Oh! Is that your Bentley, you rich old thing, you? 16. You will have only a small probability of Alzheimer’s disease if you study a language, play a musical instrument, or work puzzles. Unfortunately, you don’t do any of these things, so you aren’t going to lower you chances of Alzheimer’s. 17. If bankers were honest, they’d turn back the bonuses they got when their companies were going broke. But they’re not honest, so you know they won’t turn back those bonuses. 18. If you filed before the first, then we received your taxes on time, which we did. See how nice it is to file before the first. Invalid Argument: Denying the Antecedent If X, then Y. Not X. Therefore, not Y. Invalid Argument: Affirming the Consequent If X, then Y. Y. Therefore, X. Invalid Argument: Undistributed Middle If X, then Y. If Z, then Y. Therefore, if X, then Z. All X are Y. All Z are Y. Therefore, all X are Z.
15. 4. My chance of being born on December 25 was the same as yours. So the chances we were both born on December 25 have to be twice as good. --miscalculation of probabilities 11. Man! Three sons in a row? Your next kid is bound to be a girl. --miscalculation of probabilities/gambler’s fallacy 19. I’ll bet the Baltimore Ravens lose the coin toss today. The last Super Bowl they were in , they won it, remember? --miscalculation of probabilities
16. 5. Sodium is deadly poisonous, and so is chlorine. Salt consists of sodium and chlorine, which must be why we’re told not to eat too much of it. -- 6. The Bible commands you to leave life having made the world a better place. And therefore it commands you to make the world a better place each and every day. 12. The design team for the new project is made up of the best designer from each division of the company. So you know it is the best design team ever. 13. I like cranberry juice and I like beer. So I’m going to buy a case of this new thing, cranberry beer. 14. Voters overwhelmingly approved the reelection of Obama. Therefore, Sean Hannity overwhelmingly approved the reelection of Obama.
17. 20. Tyrannosaurs probably ate more of the fellow creatures than any other dinosaurs. After all, they were the largest carnivores on the planet during the Cretaceous period. 21. If anybody in the race, can raise their speed by four miles per hour, they will surely with the race. So, if everybody in the race can raise their speed by four miles per hour, they can all win the race. 22. I know I gave more in taxes this year! The federal gov. collected about $2.4 trillion in taxes this year, and that’s more than ever before in history.
18. What’s wrong with socialism? I’ll tell you what’s wrong with socialism. Americans don’t like it. That’s what wrong with socialism. “Everybody or most people or many believe X is right/true/good, so X must be right/true/good.”
19. Scare tactics and Argument by Force. Threatening rather than reasoning. Motivating by fear rather than reason. So you want to know why you should try to do well on these logic exercises in class today? I’ll tell you: because if you don’t, I’ll ask you to leave and not return.
20. Some people have the gift of psychic power and can read minds. Don’t believe me? Name one scientists or identify one study that proves no one has psychic power.
21. There are very good reasons for the death penalty. First, it serve as a deterrent to those who would commit capital offenses. Second, it is just and fair punishment for the crime committed. Third, reliable polls show that over 70% of all Americans favor it. Why should I put a note on this guy’s car that I just dented? Do you think he’d put a note on my car if he put a dent in it?
22. Can I prove the Biblical flood really happened? Hey, can you prove it didn’t? There is no evidence against the theory of evolution, so until someone produces that evidence, I’m going to accept the theory as a credible one.
23. Can I prove the Biblical flood really happened? Of course it happened! Why else would Noah build an ark? Stephen Colbert: “George W. Bush: great president or greatest president?”
24. I believe that when we die, we are all given new, young, perfect bodies, and we spend eternity with those whom we love.  I can’t imagine the point of life if it all just ends when we die! “Historically, marriage has been restricted to heterosexual couples. Therefore, it’s right to restrict marriage to heterosexual couples.” “You’re giving me grief for downloading music on a P2P network?? Please. Who doesn’t do that these days?
25. Hands off our freedom, atheists Letter to the editor, Times Standard   08/29/2013 I agree with Dr. Lawrence's “My Word” (”Atheists' lawsuits disrespect our nation,” Times-Standard, Aug. 20, Page A4). I am so sick and tired of atheists attacking us Christians with idiotic lawsuits. We don't try to sue atheists because they don't believe in God. If atheists want respect, they should be respectful. They twist the Constitution claiming that separation of church and state means no prayer, and no religion at all in any government office. That is not what separation of church and state means! It was put in the Constitution so the government couldn't tell us how to worship. The pilgrims came to America to escape religious persecution. My problem with atheists isn't because they don't believe like I do. My problem with them is their constant complaining and whining and filing silly expensive lawsuits. The only aim of such lawsuits has nothing at all to do with the Constitution but it is to take away the freedom of Christians. We are told by atheists that we can pray in church or at home but that we shouldn't pray in public. They tell us where we can display nativity scenes. They want prayer out of the schools. It wasn't very far back in history that schoolhouses were used as churches on Sundays. If atheists don't want to be labeled as negative then they need to keep their hands off our freedom! No, Dr. Lawrence, you need not apologize. The atheists need to give us Christians an apology. Becky Payton , Eureka