CMST A220 Essentials of Argumentation Handout on Fallacies + Exercise

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1 CMST A220 Essentials of Argumentation Handout on Fallacies + Exercise Read the chapter on fallacies in your text. I will also be lecturing on fallacies in class. Review your notes. Here are the notes from the power-point presentation on fallacies: Fallacies are flaws in reasoning, appeals and language. Fallacies in Reasoning: Hasty Generalization Composition Division Non-Sequiturs Circular Reasoning Ad Hominem False Dichotomy Post Hoc Ergo Propter Hoc Slippery Slope False Analogy Hasty Generalization (Secundum quid) Offers conclusion based on insufficient information. Too few or non-representative examples: All Native Americans walk single file, at least the one I saw did. The first five women I saw in town were women. Only women live here. My first paper was an A so I will probably get an A in the course. Refutation using hasty generalization My opponent tells you that many innocent people have been executed with the death penalty. However, if you examine her evidence, there is only one innocent person presented. She can t establish a reasonable pattern of generalization with only one case. Proof: Identify the size of the sample and the size of the population, and then show that the sample size is too small. (common sense) Fallacy of composition Unwarranted assumption that what is true of the part is true of the whole: Some Americans are poor so all Americans must have a poor standard of living. If you like eggs, peanut butter, bananas and tuna, I m sure will like this dish I just made from all four. John McCain, a Republican favors campaign finance reform so all Republicans must favor campaign finance reform. Refutation using composition John tries to get you to believe that Greece was a militaristic nation. But note that his evidence only demonstrates that a single Greek state, Sparta, was war oriented.

2 So I would say he hasn t proven that all of Greece was warlike, only Sparta. His conclusion in unwarranted. Proof: Show that the properties in question are the properties of the whole, and not of each part of member of the whole. Describe the parts to show that they could not have the properties of the whole. Fallacy of division Unwarranted assumption that what is true of the whole is true of the parts: The U.S. has a high standard of living. So, no American is poor. If you like cake, I m sure you will like pure carbon, oxygen, and hydrogen, as cake is made of all three. The ball is blue; therefore the atoms that make it up are blue. Refutation using division The reasoning from Mary is wrong when she tells you the entire brain is capable of consciousness. I will grant that she is right when she says that there are cells in the brain that are capable of consciousness. But, my evidence will demonstrate that there are only a few of these cells in the brain and claiming that the entire brain is a conscious organ clearly over claims her position. Proof: Show that the properties in question are the properties of the parts, and not the whole. Describe the parts to show that they could not have the properties of the whole. Non-sequitur Irrelevant arguments that make assumptions that do not follow from the information provided: Sex crimes are often the result of an unrestrained libido, so castration is an appropriate punishment for such crimes. The Los Angeles Times recently won 5 Pulitzer prizes. USA Today has one of the best sport sections in America. You should watch The Real World on MTV because it is a great program. Refuting a non-sequitur Look, Enrique s argument just doesn t make sense. The fact that the L.A. Times and USA today are good newspapers has no connection at all to why you should watch The Real World. So what gives? Besides, I will show you several reasons why TRW sucks. Circular Reasoning (petitio principi or begging the question) Offers as warrants and grounds statements equivalent to or identical to the claims they are supposed to support: Mohammed is the messenger of Allah because Allah caused the Koran to be written and the Koran says Mohammed is the messenger of Allah. It s wrong to make animals suffer to further scientific knowledge because making animals suffer is clearly wrong. Refutation of circular reasoning When our opponents argue that gaming is good for Native Americans they offer a

3 circular argument. They tell you this several times but if you examine the argument they never offer you any proof. They just keep claiming it is good but they never offer evidence. We prove our claims. Ad Hominem Attacking the person, rather than the argument: Ross Perot didn t know anything about NAFTA, besides, he had big ears. Siskel and Ebert are jerks. I wouldn t believe any of their movie reviews. Refuting ad hominem I don t disagree with Dieu when she says that Pete Rose lied about betting on baseball. However, the fact that he is a liar is not what qualifies him for the hall of fame. There are many liars in the hall. The standard for entry is how well you played. Pete was a great player. Period. Proof: Identify the attack and show that the character or circumstances of the person has nothing to do with the truth or falsity of the proposition being defended False Dichotomy/False Dilemma Forces listener to choose between oversimplified either/or options: Every person is either wholly good or wholly evil. The U.S. must choose to support either Israel or Palestine. Refuting a false dichotomy Let me tell you where our positions are different. Manny says we have to make a choice between conservation and energy independence. But I think that is wrong. Clearly, we don t have to choose one or the other. I think that hybrid vehicles prove that. They show we can try to meet both goals. There is plenty of middle ground. Proof: Identify the options given and show (with an example) that there is an additional option Post Hoc Ergo Propter Hoc (after this then therefore because of this) Unwarranted assumption mistaking temporal succession for causal sequence: It s raining because I washed my car yesterday. Every depression followed a Republican administration. Refuting Post Hoc Saying every war followed a Democratic administration is about as unreasonable as saying every depression followed a Republican administration. There are numerous causes for a war, just as there are numerous causes for depressions. Besides, the Viet Nam war followed a Republican administration. Proof: Show that the correlation is coincidental by showing that the effect would have occurred even if the cause did not occur, or that the effect was caused by something other than the suggested cause Slippery Slope In order to show that a proposition P is unacceptable, a sequence of increasingly unacceptable events is shown to follow from P-an illegitimate use of the if-then You should never gamble. Once you start gambling you find it hard to stop. Soon you

4 are spending all your money gambling, and eventually you will turn to crime to support your earnings. If we pass laws against fully-automatic weapons, then it won t be long before we pass laws on all weapons, and then we will begin to restrict other rights and finally we will end up living in a communist state. Thus, we should not ban fully-automatic weapons. Proof: Identify the proposition P being refuted and identify the final event in the series of events. Then show that this final event need not occur as a consequence of P. False Analogy In an analogy, two objects (or events), AandB are shown to be similar. Then it is argued that since A has property P, so also B must have property P. An analogy fails when the two objects, AandB, are different in a way which affects whether they both have property P. Government is like business, so just as business must be sensitive primarily to the bottom line, so also must government. (objectives very different-probably have to meet different criteria) Proof: Identify the two objects or events being compared and the property which both are said to possess. Show that the two objects are different in a way which will affect whether they both have that property. Fallacies of Appeal Appealing to emotion rather than reason: Ad ignoratum Ad populum Appeal to pity Appeal to fear Appeal to authority Appeal to tradition Appeal to humor Ad ignoratum (appeal to ignorance) Asks audience to accept claim solely because no evidence exists to deny its validity. Since scientists can t prove global warming will happen, it probably won t. Nicole Brown s murderer is still at large because O.J. hasn t found him. Refutation of appeal to ignorance In their first claim they say evolution is an unproven theory so it is invalid. But think about this for a minute. It s called the THEORY of evolution. Of course it s not proven. However, there are many aspects of the theory that have been proven so let s look at some of those. Those aspects are valid. Proof: Identify the proposition in question. Argue that it may be true even though we don t know whether it is or isn t. Ad Populum Asks for acceptance of a claim because it is supported by the majority of the people.

5 Most people support the death penalty so it must be right Gore should be president because he won the popular vote. Refutation of ad populum Certainly, Sam is correct when he says many people oppose gay marriage. However, many people also opposed inter- racial marriage. Today, that idea is accepted. Something is not necessarily wrong because many people oppose it. Most people used to believe the earth was flat. Appeal to pity (argumentum ad misercordiam) Arousal of sympathy in the place of reason: I hope you will accept this late paper. I was up all night working on it. Look how cute this bunny is. How could someone use it for research? Refuting appeal to pity Eileen says we should give these kids a break because they are so young. That is true. They are young. But the principles of justice don t change just because someone is young. If they killed someone, they should pay the price. Proof: identify the proposition and the appeal to pity and argue that the pitiful state of the arguer has nothing to do with the truth of the proposition Appeal to Fear Arousal of fear in the place of reason: If we take the guns from the people only the criminals will have guns. Social Security is once again threatened by Republicans. Refuting fear appeals The opposing team tells us we needed to invade Iraq because we were threatened by weapons of mass destruction. This was an appeal to fear. There is no evidence of such weapons. Proof: Identify the threat and the proposition and argue that the threat is unrelated to the truth or falsity of the proposition Appeal to authority (argumentum ad vericundiam) Authority in place of reasoning: Dr. Fraser Crane recommends the EZ Rest Hot Tub The Rock supported George Bush so he must have been the best candidate. Refuting appeal to authority The ad shows Tiger Woods driving a Buick. I seriously doubt that this is Tiger s everyday ride. But, maybe a golfer doesn t know that much about cars. If I was Tiger I would probably be driving a Porsche. Proof: Show that either the person cited is not an authority in the field or that there is general disagreement among the experts in the field on this point. Appeal to tradition Expresses a customary belief or action rather than reasoning: Well, that the way we have always done it.

6 St. Louis will win the series. Refuting appeal to tradition Fred contends that American cars have always been superior and so they are now as well. Our position is that there have been many superior cars worldwide both in the past and today. In addition, most of today s cars are made with parts produced all over the world. Appeal to humor Reduces another s claim to its most absurd conclusion: The utilities commission says we need to raise rates to get people to conserve. Soon, people will have to refinance to pay their electric bill. Wow! The government just came out with a new fifty dollar bill. Now we can pay for almost a full tank of gas with just one bill. Refuting appeal to humor Sergei claims that if global warming is accurate we will soon have beach front property in Phoenix. Not actually. But we can expect an increase in tides. This will have an effect in the U.S. Let s take a look at how. Fallacies of language The intentional or unintentional use of language that obscures or confuses the meaning of an argument. Ambiguity equivocation amphiboly Emotionally loaded language Technical language Ambiguity- Distortion or shift in meaning, used unclearly Equivocation: usually involves words-proof: Identify the word which is used twice, then show that a definition which is appropriate for one use of the word would not be appropriate for the second use Amphiboly: Usually involves grammar-proof: identify the ambiguous phrase and show the two possible interpretations Equivocation Use of a term or word in a legitimate but different sense by two or more people involved in an argument: I enthusiastically recommend this candidate with no qualifications at all. Who s on first? Refuting equivocation Let s be clear. We are being told that no candidate would be better for this job. I agree. Having no one would be better than the candidate being supported by our opposition. Proof: Identify the word which is used twice, then show that a definition which is appropriate for one use of the word would not be appropriate for the second use.

7 Emotionally loaded language Using language that avoids reasoning and seeks to alter the beliefs or actions of others through emotion: Once in a generation there is a breakthrough so revolutionary it can forever change the way you tan. This is a miracle product. Refuting emotionally loaded language Identification theft is a crime as Celina tells you. It is not however, the most heinous crime one could be affected by. I would think murder or rape might be heinous. ID theft is a money crime. Proof: Identify the prejudicial terms used. Show that disagreeing with the conclusion does not make a person (use of the term) Technical jargon Overwhelming an audience with new and unfamiliar terms in place of reasoning: Our hedge fund has a great P/E ratio so you should go big into it. The LOC is of unknown duration. Refuting technical jargon The President said I did not have sexual relations with that woman. For him, those words may technically be true. For most of us, I don t think that is the case. Identify each of the following fallacies. While there may be justification for there being apparently more than one correct answer for each fallacy some are clearly more correct than others. You may print out this page and simply write the name of the fallacy at the end of each sentence. America: Love it or leave it! Since it can't be proven that ghosts don't exist, they must exist. If I make an exception for you then I will have to make an exception for everyone. How can you say that's out? It was so close, and besides I'm down ten games to two. Polls suggest that Obama will win, so you may as well vote for him. Fred, the Australian stole my wallet. Thus, all Australians are thieves. Employees are like nails. Just as nails must be hit in the head in order to make them work, so too must employees. I took Sudafed and two days later, my cold disappeared. Since I'm not lying, it follows that I'm telling the truth.

8 The sign said "fine for parking here" and since it was "fine", I parked there. Last night I shot a burglar in my pajamas. Conventional bombs did more damage in WWII than nuclear bombs. Thus, a conventional bomb is more dangerous than a nuclear bomb. The brick wall is six feet tall. So, the bricks in the wall are six feet tall. Each brick is three inches high. So, the brick wall is three inches high. Because the brain is capable of consciousness, each neural cell in the brain must be capable of consciousness. Despite thousands of so-called sightings, no hard evidence for UFO's has ever been produced. Therefore, UFO's don't exist. We must either support animal testing, or give up in the war against cancer. That's something only a bleeding-heart liberal would believe. Everyone in a wealthy society like ours has a right to health care; therefore health care should be made universally available. Bill lives in a large building; therefore his apartment must be large. A Buick must be a good car because Tiger Woods endorses it. The soul is immortal because it lasts forever. Plea bargaining affects many people. In the second quarter of last year in Orange County there were 2,115 burglaries, 62 robberies, 109 rapes, and 2 murders.

PHI Inductive Logic Lecture 2. Informal Fallacies

PHI Inductive Logic Lecture 2. Informal Fallacies PHI 103 - Inductive Logic Lecture 2 Informal Fallacies Fallacy : A defect in an argument (other than a false premise) that causes an unjustified inference (non sequitur - it does not follow ). Formal Fallacy: