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Chapter 6 Fallacies involving Relevance: A fallacy is a common mistake in reasoning where people take the argument to be good when it is irrelevant. The.

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Presentation on theme: "Chapter 6 Fallacies involving Relevance: A fallacy is a common mistake in reasoning where people take the argument to be good when it is irrelevant. The."— Presentation transcript:


2 Chapter 6 Fallacies involving Relevance: A fallacy is a common mistake in reasoning where people take the argument to be good when it is irrelevant. The Straw Man Fallacy: Criticizing a weak or mistaken version of a person’s argument and claiming the real position is flawed is to commit the straw man fallacy. The reason it is a relevance fallacy is because the weak and mistaken version of the argument is not relevant for criticism.

3 STRAW MAN Example: “Twenty percent? You want to tip her 20%???? Hey, maybe you want to give her everything we make, but I frankly think that is ridiculous!”

4 If the advocates for prayers in public schools win on this issue, just where will it end? Perhaps next they will ask for prayers on public transportation? Prayers by government workers before they start their job each day? Or maybe, mandatory prayers in public restaurants before starting each meal might be a good idea. STRAW MAN

5 Chapter 6 The ad hominem fallacy: The ad hominem fallacy occurs when a critic attacks a person instead of arguing against the claims that the person has put forth. It is a relevance fallacy because attacking the person is not relevant to the rational acceptability of the premises of the argument. Ad hominem literally mean “against the man.”

6 Argumentum ad hominem: the most common fallacy on earth.  Example: “According to Al Gore, global warming is the most serious threat facing us today. Folks, what a crock. Al Gore spends $20,000 each year on electricity in his Tennessee mansion!”

7 Why is this fallacious? Look at it logically: Premise: All Gore spends $20,000 each year on electricity. Conclusion: Therefore global warming is not the most serious threat facing us today.

8 In case you still don’t see it: Issue: Is global warming the most serious threat? Which of the following assertions is RELEVANT? GW will cause rising sea levels to swamp all east coast cities by 2100. GW will cause coral reefs to die within 30 years. CO2 levels have risen over 30% in the last 25 years, due to GW. According to a study published in Nature, current rates of warming will lead to extinction for 1 million species by 2050. All Gore spends $20,000 a year on electricity—NOT RELEVANT!

9 ATTACK ad hominem “What Al Gore says about air pollution is a joke! That clown will say anything to get attention!”

10 CIRCUMSTANTIAL ad hominem “What Al Gore says about air pollution is pure bull. Al Gore makes a fortune from alternative energy investments. What do you think he’d say?” "I think that we should reject what Father Jones has to say about the ethical issues of abortion because he is a Catholic priest. After all, Father Jones is required to hold such views."

11 Chapter 6 Another kind of ad hominem fallacy is the circumstantial ad hominem fallacy are the tu quoque fallacy. Tu quoque literally mean “you too” and it to object to a view or advice from a person because the person doesn’t adhere to the advice. Consider this dialogue: Mom: Don’t smoke; it is bad for you. Daughter: But mom you smoke, so I should be able to. The daughter’s reply is irrelevant to the advice and is thus an instance of the tu quoque fallacy. (page 157 for more examples)

12 INCONSISTENCY ad hominem “Senator Clinton says we should get out of Iraq. What a bunch of garbage coming from her! She voted for the war, don’t forget.”

13 Chapter 6 There is one issue that we should watch for with ad hominem arguments. Sometimes when you attack the person, it is RELEVANT. If attacking the person is relevant to the argument, then it is not an ad hominem fallacy. Consider this example, Charles says to buy his diet pills, they work, he uses them. If Charles has gained weight while on the pills, it is okay to attack him for the claims made as long as it is relevant to his claims.

14 Chapter 6 The Fallacy of Guilt by Association: This fallacy of guilt by association is committed when a person or his or her views are criticized on the basis of a supposed link between that person and a group or movement believed to be disreputable. When the association is not relevant, we have another relevance fallacy. The fallacy of virtue by association claims goodness instead of guilt, but is still irrelevant.

15 Guilt by Association From Fallacies Files: The al Qaeda Cheering SectionThe most telling moment in last night's [State of the Union] speech came after the president noted that "key provisions of the Patriot Act are set to expire next year." In response, notes the New York Times, "some critics in Congress applauded enthusiastically." If Osama bin Laden watched the speech, one imagines him applauding too.

16 From Fallacies Files: Analysis of the Example: That Osama bin Laden might approve of the expiration of provisions of the Patriot Act does not show that American critics are wrong to also approve, since the reasons for their approval are different. Some Americans oppose parts of the Patriot Act because they believe that it infringes upon the rights of Americans without significantly helping to prevent terrorism. They may be wrong, but that doesn't make them an al Qaeda cheering squad.

17 Chapter 6 Fallacious Appeals to Popularity The appeal to popularity occurs when people seek to infer merit or truth from popularity. It is also know as the bandwagon fallacy or its Latin name, ad populam. It the issue in question is not the sort of thing that can or should be decided by popularity, then an ad populam fallacy has been committed.

18 “Argument” from Popularity “Everybody believes X. Therefore X is true.” Examples: “Everybody thinks God exists. Therefore, God exists.” Of course you want to buy Crest toothpaste. Why, 90 percent of America brushes with Crest!

19 Chapter 6 Fallacy of Appeal to Ignorance (ad ignorantiam) An argument exemplifies a fallacious appeal to ignorance if and only if the premises describe ignorance, lack of confirmation, lack of proof, or uncertainty regarding a statement S; and a conclusion about the truth or falsity or probability or improbability of S, or a further statement, is inferred simply on the basis of this ignorance. From ignorance we can infer only lack of knowledge. We cannot infer truth or falsity or objective probability or improbability.

20 Appeal to Ignorance [Joe McCarthy] announced that he had penetrated "Truman's iron curtain of secrecy" and that he proposed forthwith to present 81 cases… Cases of exactly what? "I am only giving the Senate," he said, "cases in which it is clear there is a definite Communist connection…persons whom I consider to be Communists in the State Department." … Of Case 40, he said, "I do not have much information on this except the general statement of the agency…that there is nothing in the files to disprove his Communist connections."

21 Chapter 6 The Burden of Proof: Often a fallacious appeal to ignorance is an attempt to shift the burden of proof (or argumentative onus) onto the other person in the debate. The idea of burden of proof is one that will vary from context to context, but attempting to shift the burden with relevance fallacies are also just justified.

22 MISPLACING THE BURDEN OF PROOF Example: “Can I prove the Biblical flood really happened? Hey, can you prove it didn’t???”

23 Examples of Burden of Proof Bill: "I think that we should invest more money in expanding the interstate system." Jill: "I think that would be a bad idea, considering the state of the treasury." Bill: "How can anyone be against highway improvements?" Bill: "I think that some people have psychic powers." Jill: "What is your proof?" Bill: "No one has been able to prove that people do not have psychic powers." "You cannot prove that God does not exist, so He does."

24 BEGGING THE QUESTION Example: “Can I prove the Biblical flood really happened? Of course it happened! Why else would Noah build an ark???”

25 Examples of Begging the Question Bill: "God must exist." Jill: "How do you know." Bill: "Because the Bible says so." Jill: "Why should I believe the Bible?" Bill: "Because the Bible was written by God." Interviewer: "Your resume looks impressive but I need another reference." Bill: "Jill can give me a good reference." Interviewer: "Good. But how do I know that Jill is trustworthy?" Bill: "Certainly. I can vouch for her."

26 Red Herring/Smokescreen An irrelevancy brought in to “support” a claim or to distract one from the issue Technically, many are Red Herrings. But we will use “Red Herring” to refer to irrelevancies we cannot put into one of our other categories.

27 We will make no distinction between a “Red Herring” and a “Smoke Screen” Example of a Red Herring: “Yes, of course the President’s strategy in Iraq is working. The Democrats sure haven’t come up with anything better!”

28 Another example of Red Herring “Yes, obviously the President’s strategy in Iraq is working. The liberal media in this country just can’t stand the thought of us winning this war.”

29 It’s also a Red Herring if you change the subject to avoid answering a question: “Why do I oppose gay marriage? I guess it was the way I was brought up.”

30 Chapter 6 Additional Relevance Fallacies: Trying to provide a categorization of all relevance fallacies would be long and not particularly useful. But there are two more general irrelevances that people use: fear and pity. The appeal to pity’s Latin name is: ad misericordiam. The appeal to fear’s Latin name is: ad baculum. These are fallacies when fear and pity are used to argue and are irrelevant to the conclusion.

31 Examples of Appeal to Pity Jill: "He'd be a terrible coach for the team." Bill: "He had his heart set on the job, and it would break if he didn't get it." Jill: "I guess he'll do an adequate job." "I'm positive that my work will meet your requirements. I really need the job since my grandmother is sick" "I should receive an 'A' in this class. After all, if I don't get an 'A' I won't get the fellowship that I want."

32 Web Sites on Fallacies

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