Logic & Argument

1. Logic & Argument Informal fallacies

2. Appeal to the PeopleArgumentum ad Populum “I’m sure that most people have cheated on a quiz some time or another; so I shouldn’t feel too bad about doing it.” [used to defend an action] “DishWatcher has more subscribers than all other satellite TV providers combined! Switch today!”[used to appeal]

3. Appeal to the PeopleArgumentum ad Populum • A fallacy in which the premise(s) of an argument are supposed to support the conclusion by stating or suggesting to the audience that most people believe or accept that conclusion; relies on the audience’s need/desire to be included among the majority • Other names/varieties: bandwagon, appeal to the majority, argument by consensus • Ad Populum to 2:11 • Ad Populum role play to 1:50

4. Straw Man “Dr. Ballard won’t even let us walk around with our shirts untucked. She doesn’t think it’s important for us to express ourselves in any way. She expects us to be robots, and that’s un-American! We should be able to untuck.”

5. Straw Man Fallacy in which the arguer distorts the opponent’s position in order to more easily defeat it, then concludes that the opponent’s real argument has been defeated. Straw Man to 2:23 Straw Man stick figures (2:23)

6. Against the Person: Abusivead Hominem “William Buckley has argued in favor of legalizing drugs such as cocaine and heroin. But Buckley is just another one of those upper-crust intellectuals who is out of touch with real America. No sensible person should listen to his pseudo-solutions.”

7. Against the Person: Abusivead Hominem Fallacy in which someone responds to his opponent’s argument by attacking the opponent personally—verbally abusing him Hitler vs. Mother Teresa to 2:45 President Obama (all 1:23)

8. Against the Person: Circumstantialad Hominem “Mrs. Casey said the new unit is going to be full of fun and practical information. But she’s an English teacher, so of course she’s gonna say that. Therefore, we can ignore what she says.”

9. Against the Person: Circumstantialad Hominem Fallacy in which the arguer attacks her opponent by bringing up circumstances that affect the opponent—with the suggestion that the opponent is predisposed or biased to argue what he does, so he shouldn’t be taken seriously

10. Appeal to PityArgumentum ad Misericordiam “Your Honor, I admit that I declared thirteen children as dependents on my tax return, even though I have only two. But if you find me guilty of tax evasion, my reputation will be ruined. I’ll probably lose my job, my poor wife will not be able to have the operation that she desperately needs, and my kids will starve. Surely I am not guilty.”

11. Appeal to PityArgumentum ad Misericordiam • Fallacy in which the arguer tries to support a conclusion by evoking pity from the listener • Different from an “argument from compassion,” in which there are logical reasons to give help or consideration—and in which a situation is not the person’s fault • Appeal to Pity (Appenstall, to 1:22) • Hillary Clinton '08 (to 4:00)

12. Slippery Slope “The students have asked the administration to put salt down on the deck so that they won’t slip. If we do that, the next thing they’ll want us to do is make hot chocolate and campfires for them to huddle around before school starts. Next thing you know, the faculty will be running heated rickshaws back and forth from the car line to the classrooms! Clearly, we cannot grant their request.” Slippery Slope: Dodge Slippery Slope: Josh & Steve(2:18) Slippery Slope: DirecTV

13. Slippery Slope Fallacy in which the conclusion depends on a supposed chain reaction when there is not sufficient reason to believe the chain reaction will take place. Slippery Slope: Dodge Slippery Slope: Josh & Steve (2:18) Slippery Slope: DirecTV

14. Hasty Generalization “Three teens were in the news this morning for vandalizing some businesses downtown. Teenagers these days are just a pack of wild animals.”

15. Hasty Generalization • Fallacy in which the arguer makes a generalization (sometimes OK), but makes it from a sample that is probably not representative; the sample may be too small or somehow atypical (not typical) of the group. • Involves a judgment call on your part.

16. Suppressed Evidence/Facts “Most dogs are friendly and pose no threat to people who pet them. Therefore, it would be safe to pet the little dog that is approaching us now.” [Little dog approaches, foaming at mouth and growling.] “During the past fifty years, Poland has enjoyed a rather low standard of living. Therefore, Poland will probably have a low standard of living for the next fifty years.”

17. Suppressed Evidence/Facts • Fallacy in which the arguer willfully suppresses or leaves out facts that would lead to another conclusion. • This fallacy is what makes some inductive arguments uncogent, remember?

18. False Dilemmaor False Dichotomy “Either I keep smoking, or I’ll get fat and you’ll hate to be seen with me.” “Either we allow abortions or we force children to be raised by parents who don't want them.”

19. False Dilemmaor False Dichotomy Fallacy where two unlikely alternatives are presented as if they were the only two available. (Sometimes the arguer goes on to eliminate the one that is supposed to be less desirable, leaving his opponent with only one “choice”) According to Jim (:25) Either you're with us... (:21)

20. Red Herring Professor Conway complains of inadequate parking on our campus. But did you know that last year Conway carried on a torrid affair with a member of the English faculty? Enough said about Conway! Environmentalists are continually harping about the dangers of nuclear power. Unfortunately, electricity is dangerous no matter where it comes from. Every year hundreds of people are electrocuted by accident.

21. Red Herring Fallacy where the arguer diverts the attention of reader/listener by changing the subject to a different but sometimes related one. Red Herring defined (to 2:26)

22. Begging the Question “Of course humans and apes evolved from common ancestors. Just look how similar they are.” “Capital punishment is justified for the crimes of murder and kidnapping because it is quite legitimate and appropriate that someone be put to death for having committed such hateful and inhuman acts.” “Ford Motor Company clearly produces the finest cars in the U.S. We know they produce the finest cars because they have the best design engineers. This is true because they can afford to pay them more than other manufacturers. Obviously they can afford to pay them more because they produce the finest cars in the U.S.

23. Begging the Question Fallacy where arguer creates the illusion that inadequate premises provide adequate support for the conclusion either (1) by leaving out a key premise, (2) by restating the conclusion as a premise, or (3) by reasoning in a circle