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Analyzing Cartoons

Cartoons combine text and images. Often, the argument of the cartoon can be found explicitly in the text. However, sometimes the argument is made by both the text and the image. This is most often done in editorial cartoons on political subjects.

Example: In the cartoon, President Bush is standing on a map of Iraq and explosions are depicted as going off on the surface of the map. Bush is saying "Terrorists are being defeated."

The combination of an image of explosions with Bush’s statement portrays an argument that claims Bush is wrong or not aware of reality. The evidence is offered via the imagery as well as the text. Neither the text nor the image, used alone, could portray this argument. Thus, it is necessary to evaluate both in a critical analysis of the argument being presented.

critical thinking_chapter05.pdf

CRITICAL THINKING

A USER’S MANUAL

DEBRA JACKSON & PAUL NEWBERRY California State University, Bakersfi eld

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Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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C H A P T E R

We started this book with a discussion about whether to support the Smoke-Free Campus Initiative. Among the arguments presented is one we identifi ed as committing a fallacy.

When you fi rst read this argument in Chapter 1, you may have realized that something isn’t quite right with it. In this chapter, you will learn exactly what has gone wrong with this argument as well as other arguments that commit fallacies. A fallacy is a mistake in reasoning of some sort, one that is rhetorically persuasive, but that on closer inspection is a bad argument. There are many different ways that an argument can go wrong, and learn- ing to detect fallacious reasoning is an important part of critical thinking, because such mistakes are notoriously common and easily overlooked. In this chapter, you will learn about six of the most common fallacies. In later chapters you will learn how to recognize other common mistakes in reasoning, which are often taken for good arguments.

Begging the Question The fallacy of begging the question occurs when the conclusion of an argument is assumed by the argument’s premises. Although technically the conclusion of the argu- ment must follow if the premises are true (after all, the conclusion is in the premises), an argument that begs the question isn’t much of an argument at all. It states, in effect, that “some claim is true because that claim is true.” This kind of argument is fallacious because it offers no evidence for its conclusion. The premise doesn’t offer a reason to accept the truth of the conclusion; it merely restates it. Consider this example.

Healthcare reform in the United States will not work since our healthcare system simply cannot be reformed.

Detecting Fallacies 5

Veronica says Are we living in a fascist state now??? The only people who would support this are uptight nonsmokers who want to take away my freedom to express myself and enjoy life. I know smoking is bad for me, but it’s my choice!

Andrew Rich/istockphoto

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92 C H A P T E R 5 Detecting Fallacies

Using the skills you learned from Chapter 3, let’s take a closer look at this argument using a Formal Analysis.

P: Our healthcare system cannot be reformed. ∴ Healthcare reform in the United States will not work.

Issue: Whether healthcare reform in the United States will work

Notice that the premise does not offer a reason to accept that the conclusion is true. Instead, it offers a restatement of the conclusion in a different sentence. To say that our healthcare system cannot be reformed is just another way of saying that healthcare reform in our country will not work. The mistake in this argument is particularly clear if you attempt to diagram it.

➀ Healthcare reform in the United States will not work since ➀ our healthcare system simply cannot be reformed.

Recall from Chapter 2 that an argument is a set of claims, one of which is supported by the other, and that different sentences can express the same claim. Given that the two sentences in this passage express the same claim, this passage contains only one claim. This means that it doesn’t really qualify as an argument at all.

Hint! You may be familiar with the phrase begs the question from everyday speech. Often when someone says, “That begs the question . . . ,” he or she means that there is some unanswered question that needs to be addressed. This should not be confused with the fallacy of begging the question.

Although sometimes it is easy to spot arguments that beg the question, most cases of question begging are not as obvious as in the previous example. Arguers may disguise the conclusion in a premise by using synonyms for terms used in the conclu- sion. Consider this example.

I just can’t believe it! Nick Newman can’t be guilty of murder since there’s no way Mr. Newman could kill someone.

Let’s fi rst present a Formal Analysis of the argument.

P: There is no way Mr. Newman could kill someone. ∴ Mr. Newman is not guilty of murder.

Issue: Whether Mr. Newman is guilty of murder

➀

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93Begging the Question

E X E R C I S E 5 . 1

Your Turn! Why are arguments that beg the question bad arguments?

C S 5 .

Your Turn! Why are arguments that beg the question bad arguments?

In this passage, the defense attorney wants to convince the jury that Nick Newman is not guilty of murder, and offers as a premise the claim that Nick Newman couldn’t be a killer. However, since the issue is whether Nick Newman is guilty of killing someone, the premise assumes that the issue has been resolved. The arguer commits the fallacy of begging the question by substituting the term kill for murder. As it stands, this is a lousy argument. There are no reasons offered for accepting the claim that Mr. Newman is not guilty of murder. Instead, the defense attorney simply restates the conclusion in a different sentence.

E X E R C I S E 5 . 2

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the fallacy of begging the question.

1. It’s clear that smoking is bad for you because it is so harmful to your health. 2. Smoking is bad for you because it causes lung cancer, heart disease, stroke,

and other cardiovascular diseases. 3. No, I do not believe that serial killers ought to be allowed to live. They have

forfeited their right to live because anyone who kills lots of people has lost that right.

4. We need to apply the death penalty for all violent murderers. This is because death is the only way to make sure that these dangerous criminals never hurt another person.

5. James is a murderer because he wrongfully killed someone. 6. James is a murderer because he has been shown to have motive, opportunity,

and no alibi for the time when the murder took place. Besides, his fi ngerprints are all over the murder weapon.

7. Adultery cannot be justifi ed. The reason is that it is simply never acceptable for a married person to have sex with someone who is not his or her spouse.

8. Adultery is always wrong. This is because it breaks a promise made to one’s spouse at the time of marriage. It also undermines the nuclear family, which is the foundation of our civilization.

9. A psychology course should be required of all college students, because obviously every university student should have to take at least one course in psychology.

10. An anatomy course should be required of all college students, because obviously every university student should know how the body works.

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94 C H A P T E R 5 Detecting Fallacies

Appeal to Ignorance The appeal to ignorance fallacy is committed when the arguer illegitimately shifts the burden of proof. An appeal to ignorance argument states, in effect, “I am right, because no one has proven otherwise.” This kind of argument is fallacious because it offers no evidence for its conclusion. The fact that your conclusion hasn’t been proven false does not establish that it is true. To convince someone that your conclusion is true, you must offer reasons for that conclusion; otherwise, you won’t convince anyone of anything.

Consider this example.

Clearly, God exists. After all, atheists have never proven that there is no God.

Here is the argument presented formally.

P: Atheists have not proven that God does not exist. ∴ God exists.

Issue: Whether God exists

Notice that we could easily provide a comparable argument for the opposite conclusion.

No one has ever proven that God exists; therefore, God does not exist.

Here is the argument presented formally.

P: No one has ever proven that God exists. ∴ God does not exist.

Issue: Whether God exists

The fi rst argument concludes that God exists, and the second concludes that God does not exist. Notice that both of these arguments deal with the same issue, namely whether God exists. Also notice that neither of these arguments are good arguments; neither offers reasons to support its conclusion. Instead, they both illegitimately shift the burden of proof to the other side of the issue. Thus, they are both examples of a fallacious appeal to ignorance. If you want to prove that some claim is true, you must supply evidence for it.

Identifying who has the burden of proof with regard to an issue is the fi rst step in determining whether the argument commits the appeal to ignorance fallacy. This can sometimes be tricky. Generally speaking, anyone trying to establish the truth of a claim has the responsi- bility to offer reasons for that claim. This burden of proof is placed on the arguer, even when the arguer’s conclusion is a true claim. Consider the case of Galileo, the famous philosopher, astronomer, and

A depiction of the Copernican system by Andreas Cellarius (1661) showing the heliocentric (sun-centered) view of the universe.

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95Appeal to Ignorance

mathematician. When he offered support for the heliocentric view of the universe (the view that Earth orbited around the sun), Galileo had the burden of proof. At the time, pretty much every other philosopher and astronomer, as well as the powerful Catholic Church, accepted the geocentric view of the universe (that the sun orbited around Earth). To estab- lish his claim that Earth orbited the sun, and not the other way around, Galileo had to offer evidence (which he did in his Dialogue Concerning the Two Chief World Systems, published in 1632). Imagine if instead of offering reasons to support his view, Galileo had given the following argument.

There should be no doubt that our glorious Earth, full of life, encircles the blazing sun, perched at the center. After all, no astronomer has ever adequately established the contrary.

E X E R C I S E 5 . 3

Your Turn! Complete a Formal Analysis of the previous argument.

C S 5 .5 . 33

Your Turn! Complete a Formal Analysis of the previous argument.

Even though this conclusion is true, the argument commits a fallacious appeal to ignorance. The failure of an opponent to prove that your belief is wrong is no evidence that you are right. If you want your reader to accept your conclusion, you must offer reasons to do so.

There are some cases in which an argument resembling an appeal to ignorance does not commit a fallacy. (That is why we say that the appeal to ignorance fallacy occurs when the arguer illegitimately shifts the burden of proof.) When the burden of proof does not lie with the arguer, the fallacy is not committed.

Consider, for example, this courtroom speech.

Ladies and gentlemen, the district attorney has not provided a shred of evidence of my client’s guilt. Therefore, you must declare the defendant “not guilty” of the charges.

In this example, the arguer claims that the defendant is “not guilty” of the charges on the basis that the defendant’s guilt has not been established. Let’s examine the argu- ment formally.

P: The district attorney has not proven that the defendant is guilty. ∴ The defendant should be declared not guilty.

Issue: Whether the defendant should be declared guilty

Although the arguer is saying, in effect, “You should accept my conclusion as true because it hasn’t been proven false,” this argument does not commit a fallacy. This is because in criminal proceedings all defendants are presumed innocent until proven guilty; the burden of proof always lies with the prosecution. In this way, when we say that a defendant should be declared “not guilty,” what we mean is that his or her guilt has not been proven, not that he or she is innocent.

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96 C H A P T E R 5 Detecting Fallacies

The fallacies of begging the question and appeal to ignorance are closely related. They both fail to do what arguments should do, namely offer reasons in support of a conclusion. Arguments that commit the fallacy of begging the question fail to offer reasons by simply restating the conclusion, typically in a disguised fashion. Arguments that commit the fallacy of appeal to ignorance fail to offer reasons by illegitimately shift- ing the burden of proof. The templates for these fallacies are described below, using C to symbolize the claim that is offered as the conclusion and the symbol � to represent the rejection of a claim.

E X E R C I S E 5 . 5

For each of the following, complete a Formal Analysis of the argument. Then, determine which side has the burden of proof. Finally, decide whether the arguer has committed the fallacy of appeal to ignorance.

1. Of course you should buy a life insurance policy! Why shouldn’t you? 2. Look, you can’t prove that extraterrestrials don’t exist. So, that means that they

are real! 3. Should the Ten Commandments be engraved onto the courthouse? Certainly.

Why shouldn’t they? 4. Angelina Jolie and Brad Pitt are having marital problems. After all, they

haven’t publicly denounced the magazine reports about their fi ghts. 5. After-death experiences are a reality. Despite years of attempts at debunking,

no one has ever been able to show that reports from beyond the grave are all due to error, deception, or wishful thinking.

6. Rape was extraordinarily rare in the American West in the nineteenth century. You can argue that it simply wasn’t reported, but I’ve never seen evidence of that.

7. It’s clear that Santa Claus exists. Every Christmas Eve, the cookies and milk we leave for Santa are eaten and packages are under the tree that weren’t there when we went to bed.

8. Listening to music on headphones is harmful to your hearing. After all, no one has shown evidence that headphones promote healthy ears!

9. The governor is clearly guilty of lying to his constituents about not providing high paying government jobs for his cronies. Not once has he shown that he was telling the truth.

10. Ghosts don’t exist, because if they did, they would exist outside the boundaries of the universe science describes, and nothing can live outside those boundaries.

E X E R C I S E 5 . 4

Your Turn! When is an argument that shifts the burden of proof to the other side not a fallacy?

C S 5 .

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97Appeal to Illegitimate Authority

E X E R C I S E 5 . 6

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the fallacy of begging the question, the fallacy of appeal to ignorance, or no fallacy is committed.

1. The government should not let the defi cit rise, because it would be bad to let it get any higher.

2. If you don’t eat your meat, you can’t have any pudding. Because, how can you have any pudding, if you don’t eat your meat?—Pink Floyd, “Another Brick in the Wall”

3. Australian shepherds must be the easiest dogs to train, because no one has ever shown that another kind of dog is easier.

4. Learning by memorization is an extremely effective way to learn. Has anyone ever shown a better way? The answer is no.

5. People with cases of the fl u should be kept in quarantine, because it’s never been disproven as the best means of keeping the disease from spreading.

6. It’s clear that my child is smart, because he is so intelligent. 7. My child is clearly smart enough to do well in school, since he scored above

average on the IQ test last year. 8. The senator must be taking illegal campaign contributions from wealthy

donors because he has never disclosed documents to show that his campaign donations are legal.

9. You should believe what the palm reader tells you, since no one has ever shown that her readings aren’t accurate.

10. Older siblings can be a good source of emotional support for the younger ones. This is because the bigger brothers and sisters can help the little ones with their feelings.

Appeal to Illegitimate Authority Since it is impossible for any one person to have knowledge about every subject, we commonly appeal to authorities to confi rm or disconfi rm claims, or to determine the best course of action. For example, when your car is not running properly, you rely on the expertise of a mechanic to diagnose the problem and return your car to work- ing order. When you disagree with your housemate about the year that the Treaty of Versailles was signed, you rely on the authority of your history textbook, or perhaps the Internet Encyclopedia of History. Notice that, in these cases, your best bet is to trust someone who is an expert on the subject in question. You do not ask your history

Begging the Question

P: C ∴ C

Issue: Whether C is true

Appeal to Ignorance

P: � C hasn’t been proven ∴ C

Issue: Whether C is true

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98 C H A P T E R 5 Detecting Fallacies

professor about auto repair, and you do not ask your auto mechanic for a lesson in European history. An argument that appeals to authority states, in effect, “You should accept this claim because an expert said it.” This kind of argument commits the fallacy of appeal to illegitimate authority when the referenced authority is not an authority on the subject in question.

The use of illegitimate authorities is notoriously prevalent in advertising. Famous athletes, musicians, and other celebrities regularly endorse products and political cam- paigns for which they have no expert knowledge. Consider this famous 1986 example featuring actor Peter Bergman, well-known to audiences for playing Dr. Cliff Warner in the daytime drama All My Children.

I’m not a doctor, but I play one on TV. If your child had a cough, she would get just what the doctor ordered. But for your cough, you play doctor at home, even playing doctor with the medicine you bought for your child. You need one of the adult formulas from Vicks, for the coughs that adults get, with the strength adults need. Formula 44 for coughs. Formula 44D for coughs with congestion. Formula 44M for coughs with congestion and a raw, irritated throat. The adult formulas. You can’t buy anything more effective.

Now, imagine you are talking with your grandmother on the phone and after hearing you cough, your grandmother offers the following argument using Peter Bergman as an authority.

Honey, you should use Vicks Formula 44, since that handsome fella who plays Dr. Warner says it’s the best.

Let’s examine the argument formally.

P: Peter Bergman says that Vicks is the best treatment for a cough. ∴ You should use Vicks cough medicine when you have a cough.

Issue: Whether you should use Vicks cough medicine when you have a cough

This is a clear example of an argument that commits the fallacy of appeal to illegitimate authority. Although it is appropriate for someone to rely on a physician’s expertise when choosing medicine to treat his or her illness, it would be foolish to rely on the tes- timony of an actor, even one who plays the role of a doctor. Of course, even legitimate experts can be wrong, and they often disagree with each other. But, if someone has no more expertise than you do on a particular issue, his or her word is not a good enough reason to accept his or her conclusion.

Note that in arguments that appeal to authority, the authority’s testimony sub- stitutes for reasons in support of the conclusion. This means that the credibility of the authority is essential to the argument. If the authority is, in fact, an expert on the subject in question and is likely to be unbiased, then his or her testimony is credible. However, if the cited authority is not an expert on the subject in question, then his or her testimony is not credible, and the argument commits the fallacy. Compare the previous fallacious argument from your grandmother to this legitimate appeal to authority from your mother.

That cough of yours sounds really bad. You should take Vicks Formula 44 since that’s what your primary care physician recommends.

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99Appeal to Illegitimate Authority

Although arguments that appeal to an illegitimate authority are fallacious, this does not mean that all arguments given by non-experts are fallacies. Consider this example from a commercial against a 2008 Washington State ballot measure.

Hello. I’m Martin Sheen with a message about Initiative 1000. It’s a dangerous idea that could be imposed on the poor, disabled, and most vulnerable in our society. Initiative 1000 tells doctors that it’s ok to give a lethal drug overdose to a seriously ill person even if they are suffering from depression. Additionally, your spouse could die by assisted suicide and you wouldn’t have to be told. People who are ill need real medical care and compassion, not lethal drugs. I’m Martin Sheen, and I’m urging you to vote “no” on Initiative 1000. Thank you.

Like your grandmother’s argument for using Vicks, this argument also involves a celeb- rity endorsement, namely one provided by an actor who played a U.S. president. How- ever, when you perform a Formal Analysis on Martin Sheen’s argument, you can see an important difference between the two arguments.

P1: Initiative 1000 could be imposed on the poor, disabled, and most vulnerable in our society.

P2: Initiative 1000 allows doctors to give a lethal drug overdose to seriously ill persons even if they are suffering from depression.

P3: Initiative 1000 allows a person to die by assisted suicide without informing his or her spouse.

∴ You should not vote for Initiative 1000.

Issue: Whether you should vote for Initiative 1000

E X E R C I S E 5 . 7

Your Turn! Provide a Formal Analysis of the previous argument.

C S 5 .

Your Turn! Provide a Formal Analysis of the previous argument.

Actor Martin Sheen is well-known for his role as President of the United States on The West Wing television series.

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100 C H A P T E R 5 Detecting Fallacies

E X E R C I S E 5 . 9

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the fallacy of appeal to illegitimate authority.

1. Vitamin water must be a great, healthy alternative to sodas. After all, I saw rapper 50 Cent drinking it in a commercial.

Unlike your grandmother’s Vicks argument, this argument does not appeal to authority. Although a famous actor, Martin Sheen, is the speaker, he does not use his testimony as a substitute for reasons in support of a conclusion.

E X E R C I S E 5 . 8

Your Turn! How can you determine when an argument that specifi es the identity of the speaker appeals to authority?

C S 5 . 8

Satellite images from NASA’s Earth Observa- tory show Tanzania’s Mount Kilimanjaro on February 17, 1993 (left) and February 21, 2000.

Hint! On many important issues, those who are experts on the subject in question disagree. Take, for example, the topic of global warming. There has been considerable debate in the United States media over whether the documented rise in global temperatures over the past 200 years is attributable to human activities. Although a large majority of scientists fi nds evidence that global warming is a result of human infl uence as evidenced in statements by national science academies and other bodies, there are many individual scientists who disagree. These dissenters include experts on the subject in question: people with degrees and careers in the fi elds of geography, geology, chemistry, meteorology, astronomy, physics, environmental science, climatology, and so on. On topics like this, in which experts disagree, it is all the more important that reasons be given to support conclusions rather than relying on appeals to authority.

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101Ad Hominem

2. Harald zur Hausen, winner of the 2008 Nobel Prize in Medicine, says that the human papilloma virus (HPV) is the leading cause of cervical cancer. So, you should consider getting screened for HPV during your annual gynecological exam.

3. Dow Constantine, who is running for King County Executive in this November’s election, was publicly endorsed by the rock band Pearl Jam. Therefore, Mr. Constantine must be the best candidate for the job.

4. Dr. Bradshaw, our family physician, has stated that the creation of muonic atoms of deuterium and tritium holds the key to producing a sustained nuclear fusion reaction at room temperature. In view of Dr. Bradshaw’s expertise as a physician, we can conclude that this is indeed true.

5. According to the Centers for Disease Control (CDC), getting the seasonal fl u vaccine is one of the best means of protection from the infl uenza virus. Sounds to me like a good reason to get vaccinated!

6. Aldous Huxley, the celebrated author of Brave New World, was convinced that wearing eye glasses actually makes the eyes weaker. Therefore, we should not get corrective glasses to improve our sight.

7. According to the American Dental Association, the best way to preserve healthy teeth and gums is by daily fl ossing. Therefore, it’s a good idea for us all to fl oss every day.

8. You really ought to try out for the basketball team because my uncle says you have real potential.

9. The National Enquirer reported that Madonna claims that heart disease can be avoided by meditation. Thus, taking up meditation should be your New Year’s resolution.

10. Meditation slows down the heart rate, and slowing the heart rate makes the heart stay free of disease. Consequently, practicing meditation should help prevent heart disease.

Hint! In an appeal to authority, whether legitimate or not, the conclusion is supported by the authority being appealed to. Thus, whether that person is a legitimate authority is relevant to whether we should accept the argument. In an ad hominem fallacy, however, the person attacked has given an argument, and the ad hominem fallaciously criticizes the arguer instead of the premises of his or her argument.

Ad Hominem The term ad hominem translates as “toward the person,” and so the ad hominem fal- lacy is also known as a fallacious argument against a person. The ad hominem fallacy occurs when an arguer rejects his or her opponent’s conclusion on the basis of some characteristic of that person, typically his or her circumstances, social position, history, or personal associations. This kind of argument is fallacious because who gives the argument is irrelevant to whether or not the argument is a good one. Bad people can give great arguments just as good people can give terrible arguments. When evaluating an argument, you should examine the truth of the premises and the logical connection between the premises and conclusion, not the source of the argument.

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102 C H A P T E R 5 Detecting Fallacies

There are three common ways that fallacious ad hominem arguments are con- structed. A person may be attacked because of his or her perceived bias, because of inconsistency in his or her words and deeds, or because of his or her psychological make-up. Some critical thinking instructors differentiate between these different types of ad hominem arguments as ad hominem abusive, ad hominem circumstantial, and ad hominem tu quoque. Although it can be helpful to recognize these different ways of attacking a person, the important lesson is that these are all fallacious attacks against the person rather than the argument itself. If you want to show that someone’s argu- ment is fl awed, you must fi nd errors in his or her reasoning. Attacking the person may sometimes be rhetorically persuasive, but it is not critical thinking.

Consider this example.

Jack argues that we should abolish capital punishment because it has no proven deterrent effect, and it has a severely negative psychological impact on the prison staff involved in executions. But, did you know that Jack’s younger brother is on death row right now? When you consider Jack’s special interest in the matter, you can see that he is wrong.

Notice that the passage contains two arguments that should not be confused. One of these is the view that the arguer opposes, and the other is the one the arguer defends. Recall from Chapter 3 that when you analyze an argument, a passage may contain extra claims that provide background information to motivate the argument. Therefore, when you analyze this passage, you should treat the argument opposed by the arguer as you would extra claims—that is, as the motivation for the argument being defended.

Moreover, since these arguments are in conversation with each other, they are engaging the same issue—in this case, whether we should abolish capital punishment. You should keep this in mind when you identify the conclusion of the argument. When the arguer writes, “He is wrong,” what exactly is he or she trying to prove? Since “he” refers to Jack, and Jack argues that we should abolish capital punishment, the conclu- sion advanced by the author of the passage must be that we should not abolish capital punishment. The Formal Analysis of the passage can then be presented as follows.

P1: Jack argues that we should abolish capital punishment. P2: Jack’s younger brother is currently on death row. ∴ We should not abolish capital punishment.

Issue: Whether we should abolish capital punishment

In this case, the arguer commits the ad hominem fallacy. Rather than fi nding a fl aw in Jack’s argument, the author attacks Jack himself as biased. However, the fact that someone may have a personal stake in an issue does not mean that his or her argument is bad. You must examine his or her reasons, not his or her motivations.

Let’s consider another example.

Bill has argued that you shouldn’t smoke cigarettes. Ha! There’s no reason to listen to him; I saw him smoking at a party last weekend.

Like the previous example, this passage refers to two arguments. One is the argument that is opposed by the author of the passage, and the other is the argument advocated by the author of the passage. Although the arguer does not provide Bill’s premises, the use

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103Ad Hominem

of the word argued signals that Bill elsewhere gives an argument for the conclusion, “You shouldn’t smoke cigarettes.” So, again this is an example of the ad hominem fallacy.

E X E R C I S E 5 . 1 0

Your Turn! Present a Formal Analysis of the previous argument.

Rather than fi nding a fl aw in Bill’s argument, the speaker attacks the source of the argu- ment, this time by pointing to Bill’s hypocrisy. However, the fact that Bill does not fol- low his own advice does not mean that Bill’s argument is fl awed. His argument stands or falls on its own merits.

Technically, not every argument which attacks a person is fallacious. To distin- guish between arguments that commit the ad hominem fallacy and those that legiti- mately criticize a person, you must pay careful attention to the issue. If the issue is about the person, then the criticism is relevant. If it is not, then focusing on the person is irrelevant to the conclusion of the argument. Consider the use of testimony in a court case. When a witness testifi es, that person’s credibility is crucial to whether or not the jury accepts his or her claims. This does not mean that the jury should simply accept the reports of all credible witnesses, since credible sources can lie or misinform, just as unreliable sources can be truthful. It does, however, mean that whether a person is credible or not is deeply relevant to whether the jury should accept his or her testimony. In any situation in which all you have to go on is a person’s word, you can regard the argument as one involving testimony.

Consider this example.

Jack Masters testifi ed that there’s no way the defendant could have committed murder. But, did you know that the defendant is Jack’s younger brother? Given his strong incentive to help his brother avoid prison time, we should question his claim.

In the earlier example about capital punishment, Jack gave evidence for his conclusion. Here, however, the only evidence given is his word. Notice the difference in the Formal Analysis of the argument.

P1: Jack testifi es that the defendant is not capable of murder. P2: The defendant is Jack’s younger brother. ∴ We should not accept Jack’s testimony.

Issue: Whether we should accept Jack’s testimony

Whenever a source is not credible, we lack suffi cient reason to accept the person’s claims. This, of course, does not mean the testimony is false. Indeed, the witness may be telling the truth. However, since the only evidence that is offered is his or her testimony, we cannot accept that testimony as convincing when the person giving it is biased.

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104 C H A P T E R 5 Detecting Fallacies

E X E R C I S E 5 . 1 2

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the ad hominem fallacy.

1. Samuel argues that extraterrestrial creatures exist. He cites the 1965 UFO crash in Roswell, New Mexico; the inexplicable crop circle phenomenon; and the hundreds of stories of abduction from people across the globe. But, this can’t be believed. Did you know that he has been diagnosed with schizophrenia?

2. Samuel told me that he was abducted by “little green men” and subjected to “experiments” when he was 12. But, this can’t be believed. Did you know that he has been diagnosed with schizophrenia?

3. Mr. Johnson’s argument that the oil deposits in Warren County will last another 100 years must be discounted. Didn’t you realize that he is the president of Lone Star Oil Company?

4. The manager of the local baseball team should be fi red immediately. He doesn’t motivate the players and he has a terrible work ethic. Besides that, he’s not honest with the fans.

5. Professor Hardy has argued that Suzy’s Law will not prevent suicides. We can ignore his argument because he is always looking for attention.

6. The economist John Flamingo may have given some pretty good reasons why we should all invest in the stock market. I, for one, don’t accept that conclusion because he hasn’t invested any of his money in the stock market.

E X E R C I S E 5 . 1 1

Your Turn! How do you decide whether an ad hominem argument is a fallacy or a legitimate argument?

Other arguments that legitimately focus on a person are ones in which the person’s character is what is at issue. Consider this one.

We should not hire John Greene for the position of chief accountant, the person responsible for managing all of our company’s accounts. This is because he has been convicted of embezzling funds from his last two employers.

Here is the argument analyzed formally.

P: John Greene has been convicted of embezzling funds from his last two employers.

∴ We should not hire John Greene for the position of chief accountant.

Issue: Whether we should hire John Greene for the position of chief accountant

Although this argument does attack a person, it is not an example of the ad hominem fallacy. John Greene’s character is what is at issue, and so the focus on him is a legitimate one.

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105Ad Hominem

7. Becky’s argument that concludes we should pay nurses higher salaries can’t be accepted. After all, her own husband just graduated from nursing school.

8. Don’t pick Frank’s Landscaping Service because they do terrible work. The last time they trimmed my trees, they killed fi ve of them.

9. Frank has argued that planting trees near your home will reduce summertime energy use. But, don’t listen to him. He owns Frank’s Landscaping Service and is just looking to increase his business.

10. William Shakespeare could not possibly have written all the plays that are attributed to him. He was only an illiterate, slow-witted actor who spent most of his time drunk. Also, he could never have had the life experiences necessary to write a play like Hamlet or Julius Caesar.

E X E R C I S E 5 . 1 3

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the appeal to illegitimate authority fallacy, the ad homi- nem fallacy, or no fallacy at all.

1. You argue that I should not eat so much red meat. That’s clearly unconvincing, since you’re no vegetarian yourself.

2. The Chinese government has been arguing that the United States should give more support to developing countries. But we should urge our legislators

The fallacies of appeal to illegitimate authority and ad hominem have similar features in that they both refer in their premises to what someone else says. Arguments that appeal to illegitimate authority are fallacious because the source referenced is not a genuine authority on the issue. This means that when the source is a legitimate author- ity, the argument does not commit the fallacy. Ad hominem arguments are fallacious because they reject a person’s argument based on features of that person rather than the reasons the person offers for his or her conclusion. If the referenced person gave testi- mony rather than an argument, the attack would not commit the ad hominem fallacy.

To distinguish between these two fallacies, you must pay close attention to whether the person referenced in the premises asserts a claim or offers an argument. When someone merely asserts a claim, all we have to go by is his or her reliability as a good source of information. But when someone offers an argument, he or she provides us with reasons that can be assessed, and so the source of the argument is irrelevant. The templates for these fallacies are described below, using C to symbolize the claim that is offered as the conclusion, P to symbolize the person referred to in the argument, and the symbol � to represent the rejection of a claim.

Appeal to Illegitimate Authority

P: (Illegitimate) P says C ∴ C

Issue: Whether C is true

Ad Hominem

P1: P argues for C P2: P is biased, hypocritical,

crazy, or the like ∴ � C

Issue: Whether C is true

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106 C H A P T E R 5 Detecting Fallacies

to discount this argument. Since when did the Chinese government provide substantial aid to developing countries?

3. The Russian government recently argued that the West should not set up a missile defense system in Eastern Europe. We should not give weight to that argument, because Russia is still locked into a Cold War mentality.

4. Former Secretary of State Henry Kissinger has urged the United States to maintain close ties with the state of Israel. Since he has so much experience in foreign relations, we should do as he says.

5. Inexpensive gasoline will be plentiful in the United States for decades yet to come. I know this because my car salesman assured me not to worry that the new car I bought gets low gas mileage. He works with cars every day, so he ought to know what he’s talking about.

6. The National Dairy Board’s argument that milk producers must be granted subsidies is completely wrongheaded. The Dairy Board just wants its members to make more money while you pay more for groceries.

7. The Roman leader Julius Caesar was not an enlightened ruler as we have been taught. In fact, his acts and exploits were merely to satisfy his enormous ego and to increase his power, not to improve the lives of the Roman people. He should be compared to Napoleon or even Hitler.

8. Claire should not be promoted to the vice president of sales position at corporate headquarters. She does not have an MBA, she is not committed to the future of the company, and the people who currently work under her complain about unfairness and favoritism. She’s not a good choice.

9. Since the quarterback of our university’s football team says that athlete’s foot can be cured by not washing your feet more than twice a week, it must be true. He’s an athlete, after all.

10. A team of archaeologists found evidence that there is an ancient graveyard on the site selected for the new Engineering building on campus. Therefore, the university has to fi nd a new location for the building.

Strawman The strawman fallacy occurs when an arguer misrepresents the conclusion of an oppos- ing view and then attacks that view in its misrepresented form. This fallacy is commit- ted in an effort to make an opponent’s view seem ridiculous or patently false, and hence easily rejected. Although this strategy may be rhetorically persuasive to those who are inclined to disagree with the opposing view, it does nothing to show that the opponent’s view is actually wrong. To show that someone’s conclusion is mistaken requires that an accurate representation of that conclusion be refuted.

Arguments that commit the strawman fallacy typically misrepresent their oppo- nent’s position by exaggerating the claims it makes, by presenting an extremist version of the position as representative of the general position, or by taking claims out of context. In each of these cases, the arguer substitutes a distorted version of the opposing conclusion.

Consider this example.

There is a growing movement for the recognition of a right to pray in public schools. But we should not require every child to recite the Lord’s Prayer at mealtimes. Protestants and Catholics say the prayer differently. Some children don’t even know the prayer. And the parents of non-Christians might not want their children to learn it.

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107Strawman

Like arguments that commit the ad hominem fallacy, an argument containing a straw- man fallacy can be diffi cult to analyze because the passage will refer to two differ- ent conclusions—one that is associated with the original argument being opposed, the other that is the straw, or distorted, version. Therefore, you must take care to recognize the original argument and identify the issue from that. In this case, the issue being debated is whether we should recognize a right to pray in public schools. Next, you can analyze the argument. When you compare the original issue to the straw conclusion, the distortion becomes apparent. The Formal Analysis of the argument is as follows.

P1: Protestants and Catholics say the Lord’s Prayer differently. P2: Some children don’t even know the Lord’s Prayer. P3: The parents of non-Christians might not want their children to learn the

Lord’s Prayer. ∴ We should not require every child to recite the Lord’s Prayer at mealtimes.

Issue: Whether we should recognize a right to pray in public schools

In this example, all of the premises are relevant to whether we should require all stu- dents to recite the Lord’s Prayer at mealtimes. However, this is not the conclusion rele- vant to the original issue. The arguer substitutes the conclusion “We should not require every child to recite the Lord’s Prayer at mealtimes” as if it countered the opposition’s conclusion that “We should recognize a right to pray in public schools.” But, it does not. Instead, the distortion of the main conclusion commits the strawman fallacy.

Here’s another example.

Colin Powell, former Secretary of State and Chairman of the Joint Chiefs, has argued that the United States should never engage in torture. It’s clear that Powell thinks we shouldn’t even be allowed to ask dangerous terrorists simple questions. Such a “hands off” attitude will be a disastrous foreign policy, and it will lead to more brazen attacks against the United States. I think Powell is really wrong on this one.

E X E R C I S E 5 . 1 4

Your Turn! What is Powell’s conclusion? What, then, is the issue up for debate?

Once you have the issue identifi ed—the one from Colin Powell’s argument—the Formal Analysis of the argument reveals the distortion of his conclusion.

P1: Not being allowed to ask dangerous terrorists simple questions will be a disastrous foreign policy.

P2: Not being allowed to ask dangerous terrorists simple questions will lead to more brazen attacks against the United States.

∴ The United States should be able to ask dangerous terrorists simple questions.

Issue: Whether the United States should engage in torture

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108 C H A P T E R 5 Detecting Fallacies

E X E R C I S E 5 . 1 5

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the strawman fallacy. When the fallacy is committed, explain how the arguer distorts his or her opponent’s conclusion.

1. Look, maybe you think it’s okay to legalize tribal casinos, but I don’t. Letting every random group of people in the country open a casino is a ridiculous idea, and one that is bound to cause trouble.

2. Look, maybe you think it’s okay to legalize tribal casinos, but I don’t. More casinos means more gambling, and more gambling means more gambling addicts. Also, organized crime is never far away from casinos, and that’s the last group we need to subsidize. I say, let’s stop the casinos on the reservations.

3. Anti-abortion groups have given a number of reasons why they oppose abortions. But what these groups really want to do is outlaw every form of birth control, and that is clearly a bad idea. Not everyone can afford to have a child, and legal birth control allows families to plan their pregnancies. Clearly, we should oppose the anti-abortion conclusion.

4. Many people criticize television as being the major cause of ADHD (Attention Defi cit Hyperactivity Disorder) among children. Maybe this once was true, but it isn’t any longer. Children are now surfi ng the Internet and playing video games instead of watching television.

5. Old-school soccer fans argue that using instant-replay technology to resolve questionable referee calls will slow down the game. But, this isn’t necessarily true. Teams could be limited to one challenge per half, and many challenges would involve disputed goals, when play is already stopped.

6. I know that education experts argue that a multicultural curriculum in elementary school will lead to more tolerance and fewer biases toward those perceived as “different.” But we should reject teaching nothing but multicultural dogma. It would leave our students defi cient in the basic skills they need to learn such as math, reading, and science.

7. Some feminists argue that the traditional model of marriage and family is oppressive to women. However, it is clearly a ridiculous idea to get rid of families. This would mean that our children would either be raised by government bureaucrats and housed in prison-like facilities, or they would be left to roam the streets and raise themselves.

8. Psychologists claim that research shows the Rorschach inkblot test reveals a person’s unconscious motivations and drives, and for that reason want to test children who are disruptive in school. But psychoanalyzing everyone in the country would be foolish. It would be too invasive and expensive for a nation like ours.

This argument commits the strawman fallacy. The arguer provides reasons to support the claim that “The United States should be able to ask dangerous terrorists simple questions.” However, this claim is not the rejection of the opposing view; instead, it distorts Powell’s conclusion. The arguer, thus, does not address what’s at issue, yet acts as if he or she has done so when claiming that “Powell is really wrong on this one.”

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109Red Herring

9. Some employers argue that they have the right to monitor employee Internet use. I completely disagree. Why should employers be allowed to spy on the private lives of their employees and learn everything about them? No one supports such an intrusion by Big Brother.

10. You argue that we should increase our military force in Afghanistan. Clearly you don’t care about Americans. If you did, you wouldn’t want them to go die overseas.

Hint! The term red herring comes from the practice of taking a fi sh that has been cured in brine or heavily smoked and dragging it across a trail to throw tracking dogs off the scent of the person or animal they are pursuing.

Occasionally arguments that commit the red herring fallacy contain premises that are obviously irrelevant. However, in most cases the fallacy is not so blatant. These arguments often involve topics which evoke a strong emotional response, and it is this response that distracts you from the issue and tricks you into accepting the conclusion.

Consider this argument.

Environmentalists argue that the construction of 30 new dairies in Tippecanoe County will endanger public health, worsen our air quality, and contaminate the ground and surface water. However, the fact of the matter is that each new dairy will create hundreds of new jobs for our county’s residents, and the property taxes paid by the dairies will provide us with the revenue needed to fund important programs for our community. When you consider the benefi ts to come, it’s clear that the environmentalists are wrong.

Notice that, as in the ad hominem and strawman fallacies, there are two different views presented in the passage. The arguer begins by stating the view of his or her opponent. You must be sure that you do not confuse the opponent’s argument with that of the author of the passage. At the end of the passage, the arguer states the environmentalists are wrong. But what exactly are they wrong about? The environmentalists contend that the proposed dairies will endanger public health, worsen air quality, and contaminate

Red Herring The red herring fallacy is a fallacy in which the arguer provides premises that do not support the conclusion they claim to support; instead, the arguer deliberately attempts to distract you by providing reasons that are irrelevant to the issue in question. Determining whether a passage commits the red herring fallacy requires that you fi rst identify the conclusion. Once you have the conclusion identifi ed, you can ask whether the premises provided are actually relevant to it.

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110 C H A P T E R 5 Detecting Fallacies

Lower Ninth Ward residents stranded on roofs wait for rescue boats in New Orleans on August 29, 2005.

the water. Since the arguer disagrees with the environmentalists, the conclusion of the argument, then, is that the proposed dairies will not endanger public health, worsen air quality, or contaminate the water supply. Let’s present the argument formally.

P1: Each new dairy will create hundreds of new jobs for the residents of Tippecanoe County.

P2: Each new dairy will provide property tax revenue needed to fund important community programs.

∴ The new dairies will not endanger public health, worsen air quality, nor contaminate the water supply.

Issue: Whether the new dairies will endanger public health, worsen air quality, and contaminate the water supply

Once you have the conclusion identifi ed, it is much easier to determine whether the premises are relevant or irrelevant. Although these premises may be good reasons to support the construction of the dairies, they do not establish that the dairies will not have harmful effects on public health, air quality, and water supplies. The argument, thus, commits the red herring fallacy because it provides premises that distract the reader from the issue in question.

Let’s consider one more example.

Some critics argue that the delayed government response to the fl ooding in New Orleans following Hurricane Katrina is a result of racism and classism. But this just isn’t true. Hurricane Katrina rapidly grew from a Category 3 storm to a Category 5 storm in less than nine hours. At peak strength, winds reached 175 miles per hour and a minimum central pressure of 902 mbar, making it, at that time, the strongest hurricane recorded in the Gulf of Mexico.

M ar

ko G

eo rg

ie v/

G et

ty Im

ag es

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111Red Herring

E X E R C I S E 5 . 1 7

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the red herring fallacy.

1. Opponents of increased oil drilling offshore contend that more drilling will be dangerous to the marine environment. This isn’t true. Offshore drilling will provide hundreds of local jobs, improve the local economy, and decrease our reliance on energy importation. So, you must agree that increased drilling offshore will not be dangerous to the marine environment.

2. Many have applauded the success of welfare reform in helping people make the transition from welfare to employment. However, Lester Spence, a political science professor at Johns Hopkins University, argues that we must recognize that welfare reform has not helped people transition from welfare to solidly working-class lives. First, the employment found by former welfare recipients does not pay well enough to support a family. Second, parents who are unable to afford child care costs routinely leave their children at home to fend for themselves. And, fi nally, the jobs obtained by former welfare recipients rarely include healthcare benefi ts.

3. A recent Highway Patrol report maintained that texting while driving is as dangerous as drinking and driving. I completely disagree. Texting is a great

E X E R C I S E 5 . 1 6

Your Turn! What conclusion is being opposed by the author of this passage? What, then, is the issue up for debate?

E X E R C IC S ES 5 .5 . 1 66

Your Turn! What conclusion is being opposed by the author of this passage? What, then, is the issue up for debate?

Once you have the issue identifi ed, you can then identify the conclusion of the argu- ment and determine whether or not the premises are relevant to it. The Formal Analysis of the argument is as follows.

P1: Hurricane Katrina rapidly grew from a Category 3 storm to a Category 5 storm in less than nine hours.

P2: At peak strength, Hurricane Katrina’s winds reached 175 miles per hour and a minimum central pressure of 902 mbar.

P3: Hurricane Katrina was, at that time, the strongest hurricane recorded in the Gulf of Mexico.

∴ The delayed government response to the fl ooding in New Orleans follow- ing Hurricane Katrina is not a result of racism and classism.

Issue: Whether the delayed government response to the fl ooding in New Orleans following Hurricane Katrina is a result of racism and classism

In analyzing the argument, you can see that the premises do not support the conclusion the arguer purports to defend. Instead, the premises distract the reader from the issue that is being debated. The argument, then, commits the red herring fallacy.

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112 C H A P T E R 5 Detecting Fallacies

way to stay in touch with family and friends. You can send someone a message whenever you want. What’s more, it’s fun! It’s plain that this author is completely misguided about texting.

4. The nurses at the local hospital contend that they should get a pay raise. But many people in this world don’t even have jobs. They get by on handouts, charity, and what little they can earn through day labor. The hospital administration should say “no” to this raise.

5. Lots of political commentators say that the fi rst piece of business for the new Congress should be to pass income tax reform that helps the very poorest people in this country. I agree for several reasons. First, the people on the bottom of the economic ladder suffer tremendously from sales taxes. Second, these overworked, overtaxed people lose much of their pitifully small income to federal income tax. Also, many are so poorly educated that they can’t fi nd legal means to protect their hard-won dollars.

6. A recent study showed that learning to play the piano helps children do better at math. However, this just isn’t true. Pianos cost a lot of money, lessons are diffi cult to arrange, and most people lack suffi cient room for such a large instrument.

7. In your editorial, you argued that the graduates of our social work program are not prepared for jobs in the private sector. This is simply false. The private sector is a wonderful place to work, and many jobs are being created in the private sector each year. Small- and medium-sized businesses create more than their share of jobs, and the pay is above average for the fi eld.

8. Some historians contend that the United States did not need to drop the atomic bomb on Japan in order to win World War II. However, developing nuclear energy has been an important advance toward energy independence. Many countries without oil reserves can realize their dream to modernize and restrain energy costs just by building some nuclear power plants.

9. A popular American history text used in college courses argues that nationalism was a volatile force in the mid-nineteenth century. But this can’t be supported. Without nations we would be living in tribal groups, fi ghting with other tribes over hunting territories. It is nationalism that has allowed the human race to make progress in combating disease, malnutrition, superstition, and many other evils people experience in tribal culture.

10. In 1998, the Arizona Supreme Court ruled that declaring English as the state’s offi cial language deprives people of their fundamental First Amendment right to access government and deprives government offi cials of their rights to free speech. These judges are clearly wrong since the majority of the population of Arizona speaks English. To be successful in school and in one’s career, speaking English is a must.

The strawman and red herring fallacies can be diffi cult to distinguish. Both argu- ments that commit the strawman fallacy and those that commit the red herring fallacy refer to the opposing view as the motivation for their arguments. Strawman arguments are fallacious because, rather than offering premises that support rejecting the oppo- nent’s conclusion, they offer reasons to reject a distorted version of the opponent’s con- clusion. In this way, the argument does not address the issue up for debate. Red herring arguments are fallacious because the arguer distracts the reader from what’s at issue by

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113Red Herring

providing premises that are irrelevant to the conclusion they are intended to support. The templates for these fallacies are described below, using C to symbolize the claim that is offered as the conclusion and the symbol � to represent the rejection of a claim.

E X E R C I S E 5 . 1 8

For each of the following, complete a Formal Analysis of the argument. Then, determine whether the argument commits the strawman fallacy, the red herring fallacy, or no fal- lacy is committed.

1. A bunch of fanatics have been clamoring for restrictions on alcohol use by pregnant women to prevent fetal alcohol syndrome. They forget that alcohol is a perfectly normal part of society. It can help people relax in social situations and make people feel happy. Why, virtually every culture on Earth has used alcohol for a relaxant.

2. The governor has argued that the state could save much-needed funds through the early release of nonviolent offenders who have served at least 90% of their sentences. Why does the governor want people who commit crimes to escape all punishment? Letting these dangerous felons loose in the streets will just lead to more crime and endanger more lives.

3. The head of our employees union contends that the new contract should include a raise that keeps employee wages in line with infl ation. But using all the company savings just to enrich the employees is a bad idea. Why, we need to pay for additional inventory, need to pay our suppliers, and need to put money away for a rainy day. I urge the board to resist the union’s demand for raises.

4. I’ve heard statistics used to show that wearing seatbelts in a moving vehicle saves lives. But this is ridiculous. Cars are one of the most useful modern conveniences of the twentieth century. They provide us with a relatively cheap and easy way to travel quickly across great distances. If it weren’t for cars, we’d be stuck walking or riding horses to work every day.

5. Some people argue that the death penalty is no more of a deterrent to crime than life in prison without parole. But, I disagree. What’s to stop convicted murderers from killing prison guards and other prisoners while they’re incarcerated?

6. You have probably heard arguments against suspending athletes who use performance enhancers. How can the integrity of sports be maintained if we just let them off with no penalties at all? Competition is unfair if athletes are allowed to cheat without consequences. Therefore, we must penalize athletes who cheat if we want to ensure the quality of sports.

7. You may be aware of the recent proposal to create a pub on campus that would sell beer and wine to adult students. Having the entire campus drunk

Strawman

P: Premises ∴ � C (distorted)

Issue: Whether C is true

Red Herring

P: Premises (irrelevant) ∴ C

Issue: Whether C is true

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114 C H A P T E R 5 Detecting Fallacies

day and night is a bad idea and one we all should oppose. It will only lead to violence, destruction of property, and a dramatic decline in academic performance.

8. Recently animal rights supporters charged that horse racing can cause life- threatening injuries to young animals. This doesn’t make sense. Horse racing is not only an important source of jobs for thousands of people, it also provides thrilling entertainment for untold numbers of spectators and bettors across the country.

9. Horse racing is a popular sport all across the country. But did you realize that racing a horse before it is fully mature can result in life-threatening leg injuries? This is because the leg bones of young horses are not very strong, and if the leg bones are not strong, then injury can easily result.

10. The attorney general is advocating that the Miranda warnings automatically given to suspects in criminal cases should be withheld when police apprehend terror suspects. This would be a step backward for justice in this country. After all, Miranda rights are so common that every person in the country knows the name. Even television shows constantly have suspects being read their Miranda rights.

Putting It All Together: A Basic Analysis Plus Fallacy Identifi cation

In Chapter 2, you learned how to recognize arguments and to distinguish them from explanations and passages that are neither arguments nor explanations. In Chapters 3 and 4, you learned how to analyze the parts of an argument and to diagram them. In this chapter, you have learned to identify some common forms of fallacious reasoning. Now, you can put all these skills together in paragraph form.

Directions for a Basic Analysis plus Fallacy Identifi cation

In paragraph form, use complete sentences and proper English grammar and spelling to do the following.

Step 1: Write a Basic Analysis of the passage. (You may want to refer to the Directions for Basic Analysis, Chapter 3, page 49.)

Step 2: If the passage contains an argument, determine whether the argument commits a fallacy. If it does, write a separate paragraph identifying the fallacy committed, and explaining how this fallacy is committed.

Step 3: If the argument does not commit a fallacy, diagram it and verify that the diagram is consistent with your Basic Analysis.

Putting It All Together: A Basic Analysis Plus Fallacy Identifi cation

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115Putting It All Together: A Basic Analysis Plus Fallacy Identifi cation

Let’s examine the argument by Veronica referred to at the start of this chapter. Recall that this was her response to Davion’s argument for banning smoking in public places. Here are the two posts again.

Davion says If you want to subject yourself to the health risks of smoking, that’s fi ne. But smoking in public places should be banned. Why? It’s simple. Smoking poses a health risk to others, and anything that does that should be outlawed. Period.

Before analyzing Veronica’s post, you need to analyze Davion’s because she is respond- ing to him. First, notice that Davion’s post contains an argument, even though not every claim in it plays a role in the argument. Therefore, diagram it as follows.

➀ If you want to subject yourself to the health risks of smoking, that’s fi ne. But ➁ smoking in public places should be banned. Why? ➂ It’s simple. ➃ Smoking poses a health risk to others, and ➄ anything that does that should be outlawed. Period.

➃ ➄

➁

Next, write a Basic Analysis of the argument.

This passage by Davion contains an argument. The issue is whether smoking in public places should be banned. The conclusion is that smoking in public places should be banned. The fi rst premise is that smoking poses a health risk to others. The second premise is that anything that poses a health risk to others should be outlawed.

Now, let’s turn to Veronica’s post. Given that she is responding to the previous posts, the issue is the same, namely “whether we should ban smoking in public places.” Unfor- tunately, Veronica attacks supporters of the ban on smoking such as Davion for being “fascists” rather than offering reasons why their argument might be fl awed. Therefore, the Basic Analysis should read as follows.

This passage by Veronica contains an argument. The issue is whether we should ban smoking in public places. The conclusion is that we should not ban smoking in public places. The premise is that the only people who would support the ban on smoking are uptight nonsmokers who want to take away my freedom to express myself and enjoy life.

This argument commits the ad hominem fallacy because the arguer attacks the source of the argument rather than addressing the argument itself.

Notice that Veronica’s argument is not diagrammed because it commits a fallacy.

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116 C H A P T E R 5 Detecting Fallacies

E X E R C I S E 5 . 1 9

Complete a Basic Analysis plus fallacy identifi cation for each of the following passages. 1. There’s nothing wrong with downloading pirated copies of movies because my

roommate said that it’s not cheating anyone. 2. Richard Nixon has to be one of the worst presidents in the history of this

country. Look at his record: lies, corruption, and scandal. Plus, he is the only president forced to resign the offi ce.

3. State-perpetrated or -tolerated physical violence towards an identifi able group could not occur unless it is preceded by symbolic violence.—A. L. Hinton, Annihilating Difference

4. Because fraud is an evil peculiar to man, it more displeases God. Therefore the fraudulent are the lower, and so more pain assails them.—Dante, The Inferno

5. Angela Smith has given a stirring argument opposing the storage of radioactive waste on Native American lands. But we can dismiss her conclusion, since her grandparents were members of the Iroquois nation.

6. No one has ever demonstrated that Iraq didn’t have WMDs. In the absence of such evidence, isn’t it reasonable to conclude that they did have them?

7. You don’t think that Iran is most likely planning to build a nuclear weapon? Well, you’re wrong. They have embarked on plutonium enrichment, and that is not necessary for a nuclear power plant.

8. If a person is over the age of 16, he or she should be considered an adult. This is because if a person is over the age of 16, then he or she can get a driver’s license, and if a person can get a driver’s license, then he or she should be considered an adult.

9. Some say that only losers who don’t know how to have a good time save for retirement. This attitude is just false. The reality is that if you manage your fi nances effi ciently and start working towards your goals sooner, you can spend more in the long run. Besides, who says spending all your money is the only way to have fun?—Eric Tyson, Personal Finances for Dummies

10. Beyond the age of 65, widowhood increases geometrically because of the higher death rate of men.—John Weeks, Population: An Introduction to Concepts and Issues

11. NRA supporters have argued that responsible citizens should be able to legally own fi rearms. This is just ridiculous. Letting every American run around armed with surface-to-air missiles and rocket launchers will just lead to chaos and death on a massive scale. We clearly would be ruining our country with such policies.

12. A team of engineers found that Hurricane Katrina damaged the structural integrity of the Lake Pontchartrain bridge. Therefore, the bridge will have to be closed until its safety can be assured.

13. Peter Singer argues that the treatment of chickens in factory farms is inhumane. But Singer is just plain wrong. Chicken is a great source of protein, and is signifi cantly healthier than beef or pork.

14. It would weaken a story like A Couple of Hamburgers if the author tried to describe directly the feelings that lie beneath such actions or if he intruded into his story with explanatory comments of his own—Arthur Mizener, Modern Short Stories

15. Some people argue that we should increase foreign aid to Pakistan. But this is a terrible idea! Pakistan is currently too unstable and their regime is corrupt.

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117Chapter Review Questions

Furthermore, they may use the money to attack neighboring countries like India.

16. Occupational therapy is a profession that should have more men in it, because it currently has too many women.

17. Occupational therapy is the best profession to go into in the near future, because as the baby boomers age, they will be needing more and more help with the living skills taught by occupational therapists.

18. Critics of NASA’s space program contend that the money spent on space exploration could be better spent here on Earth. I heartily disagree. People are natural explorers, and space offers the last frontier for us to explore. Furthermore, the technology that will result from the space program will have many uses in satellite and missile defense systems.

19. Since food allergies can cause serious illness for young people, the government should educate parents about the need to take food allergies seriously and also should provide free allergy screenings for children.

20. The curvature of the earth’s surface is very similar to that of a sphere. Because of this curvature, surveys are divided basically into geodetic surveys and plane surveys.—Department of the Army, Elements of Surveying

Chapter Review Questions

1. Defi ne fallacy. 2. What does it mean to say that an argument begs the question? 3. How do you determine who has the burden of proof? 4. How do you know when an argument commits the fallacy of appeal to

illegitimate authority? 5. When is an argument that attacks a person not an ad hominem fallacy? 6. What mistake does an arguer make when committing the strawman fallacy? 7. What is the error in reasoning when an arguer commits the red herring fallacy?

Ch t R i Q ti

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311A N S W E R S T O S E L E C T E D E X E R C I S E S

Chapter 5

E X E R C I S E 5 . 2

3. Begging the question

P: Anyone who kills lots of people has lost the right to live.

∴ Serial killers have forfeited their right to live.

Issue: Whether serial killers have forfeited their right to live

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This page contains answers for this chapter only

312 A N S W E R S T O S E L E C T E D E X E R C I S E S

6. Not a fallacy

P1: James had motive, opportunity, and no alibi for the time when the murder took place.

P2: James’ fi ngerprints are all over the murder weapon. ∴ James is a murderer.

Issue: Whether James is a murderer

9. Begging the question

P: Every university student should have to take at least one course in psychology.

∴ A psychology course should be required of all college students.

Issue: Whether a psychology course should be required of all college students

E X E R C I S E 5 . 5

3. The arguer has the burden of proof, so this commits the fallacy of appeal to ignorance.

P: No one has shown why the Ten Commandments should not be engraved onto the courthouse.

∴ The Ten Commandments should be engraved onto the courthouse.

Issue: Whether the Ten Commandments should be engraved onto the courthouse

6. The arguer has the burden of proof, so this com- mits the fallacy of appeal to ignorance.

P: No one has presented evidence that rape wasn’t reported in the American West in the nineteenth century.

∴ Rape was extraordinarily rare in the American West in the nineteenth century.

Issue: Whether rape was extraordinarily rare in the American West in the nineteenth century

9. The arguer has the burden of proof, so this com- mits the fallacy of appeal to ignorance.

P: Not once has the governor shown that he was telling the truth to his constituents about provid- ing high paying jobs for his cronies.

∴ The governor lied to his constituents about providing high paying government jobs for his cronies.

Issue: Whether the governor lied to his constituents about providing high paying government jobs for his cronies

E X E R C I S E 5 . 6

3. Appeal to ignorance

P: No one has ever shown that another kind of dog is easier to train than an Australian shepherd.

∴ Australian shepherds are the easiest dogs to train.

Issue: Whether Australian shepherds are the easiest dogs to train

6. Begging the question

P: My child is so intelligent. ∴ My child is smart.

Issue: Whether my child is smart

9. Appeal to ignorance

P: No one has ever shown that the palm reader’s readings aren’t accurate.

∴ You should believe what the palm reader tells you.

Issue: Whether you should believe what the palm reader tells you

E X E R C I S E 5 . 9

3. Appeal to illegitimate authority

P: Dow Constantine was publicly endorsed by the rock band Pearl Jam.

∴ Dow Constantine is the best candidate for the job of King County Executive.

Issue: Whether Dow Constantine is the best candidate for the job of King County Executive

6. Appeal to illegitimate authority

P: Aldous Huxley was convinced that wearing eye glasses makes the eyes weaker.

∴ We should not get corrective glasses to improve our sight.

Issue: Whether we should get corrective glasses to improve our sight

9. Appeal to illegitimate authority

P: Madonna claims that heart disease can be avoided by meditation.

∴ Taking up meditation should be your New Year’s resolution.

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313A N S W E R S T O S E L E C T E D E X E R C I S E S

Issue: Whether taking up meditation should be your New Year’s resolution

E X E R C I S E 5 . 1 2

3. Ad hominem

P1: Mr. Johnson argues that oil deposits in Warren County will last another 100 years.

P2: Mr. Johnson is the president of Lone Star Oil Company.

∴ The oil deposits in Warren County will not last another 100 years.

Issue: Whether the oil deposits in Warren County will last another 100 years

6. Ad hominem

P1: The economist John Flamingo argues that we should all invest in the stock market.

P2: The economist John Flamingo hasn’t invested any of his money in the stock market.

∴ We should not invest in the stock market.

Issue: Whether we should all invest in the stock market

9. Ad hominem

P1: Frank has argued that planting trees near your home will reduce summertime energy use.

P2: Frank is just looking to increase his landscaping business.

∴ Planting trees near your home will not reduce summertime energy use.

Issue: Whether planting trees near your home will reduce summertime energy use

E X E R C I S E 5 . 1 3

3. Ad hominem

P1: The Russian government recently argued that the West should not set up a missile defense system in Eastern Europe.

P2: Russia is still locked into a Cold War mentality. ∴ The West should set up a missile defense sys-

tem in Eastern Europe.

Issue: Whether the West should set up a missile defense system in Eastern Europe

6. Ad hominem

P1: The National Dairy Board has argued that milk producers must be granted subsidies.

P2: The Dairy Board just wants its members to make more money while you pay more for groceries.

∴ Milk producers should not be granted subsidies.

Issue: Whether milk producers should be granted subsidies

9. Appeal to illegitimate authority

P: The quarterback of our university’s football team says that athlete’s foot can be cured by not washing your feet more than twice a week.

∴ Athlete’s foot can be cured by not washing your feet more than twice a week.

Issue: Whether athlete’s foot can be cured by not washing your feet more than twice a week

E X E R C I S E 5 . 1 5

3. This argument commits the strawman fallacy. The conclusion this arguer supports is an exaggerated version of the abortion opponent’s stance. They do not call for the elimination of all birth control.

P1: Not everyone can afford to have a child. P2: Legal birth control allows families to plan their

pregnancies. ∴ Outlawing every form of birth control is a bad

idea.

Issue: Whether abortion should be opposed

6. This argument commits a strawman fallacy, because the arguer distorts the view of those favoring a mul- ticultural curriculum. They do not say they favored teaching nothing but multicultural “dogma.”

P: Teaching nothing but multicultural dogma will leave our students defi cient in the basic skills they need to learn such as math, reading, and science.

∴ We should reject teaching nothing but multicultural dogma.

Issue: Whether a multicultural curriculum in elementary school will lead to more tolerance and fewer biases toward those perceived as “different”

9. This argument commits the strawman fallacy, because the arguer distorts the view of the

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314 A N S W E R S T O S E L E C T E D E X E R C I S E S

employers. They do not say that they want to spy on the private lives of their employees and learn everything about them.

P: No one supports Big Brother spying on employees’ private lives to learn everything about them

∴ Employers should not be allowed to spy on the private lives of their employees and learn everything about them.

Issue: Whether employers have the right to monitor employee Internet use

E X E R C I S E 5 . 1 7

3. Red herring fallacy

P1: Texting is a great way to stay in touch with family and friends.

P2: Texting allows you to send someone a message whenever you want.

P3: Texting is fun. ∴ Texting while driving is not as dangerous as

drinking and driving.

Issue: Whether texting while driving is as dangerous as drinking and driving

6. Red herring fallacy

P1: Pianos cost a lot of money. P2: Piano lessons are diffi cult to arrange. P3: Most people lack suffi cient room for such a

large instrument as a piano. ∴ Learning to play the piano does not help

children do better at math.

Issue: Whether learning to play the piano helps children do better at math

9. Red herring fallacy

P1: Without nations we would be living in tribal groups, fi ghting with other tribes over hunting territories.

P2: Nationalism has allowed the human race to make progress in combating disease, malnutrition, superstition, and many other evils people experience in tribal culture.

∴ Nationalism was not a volatile force in the mid-nineteenth century.

Issue: Whether nationalism was a volatile force in the mid-nineteenth century

E X E R C I S E 5 . 1 8

3. Strawman fallacy

P1: We need to pay for additional inventory. P2: We need to pay our suppliers. P3: We need to put money away for a

rainy day. ∴ Using all the company savings just to enrich

the employees is a bad idea.

Issue: Whether the new contract should include a raise that keeps employee wages in line with infl ation

6. Strawman fallacy

P: Competition is unfair if athletes are allowed to cheat without consequences.

∴ The integrity of sports cannot be maintained if we just let athletes who use performance enhancers off with no penalties at all.

Issue: Whether we should suspend athletes who use performance enhancers

9. No fallacy

P1: The leg bones of young horses are not very strong. P2: If the leg bones of young horses are not strong,

then injury can easily result. ∴ Racing a horse before it is fully mature can

result in life-threatening leg injuries.

Issue: Whether racing a horse before it is fully mature can result in life-threatening leg injuries

E X E R C I S E 5 . 1 9

3. This passage from A. L. Hinton’s Annihilating Difference contains neither an argument nor an explanation. Both arguments and explanations require a minimum of two claims, and this passage contains only one claim.

6. This passage contains an argument. The issue is whether Iraq had WMDs. The conclusion is that Iraq did have WMDs. The premise is that no one ever showed Iraq did not have WMDs.

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315A N S W E R S T O S E L E C T E D E X E R C I S E S

This argument commits the fallacy of appeal to ignorance, because the arguer illegitimately shifts the burden of proof.

9. ➀ Some say that only losers who don’t know how to have a good time save for retirement. ➁ This attitude is just false. The reality is that ➂ if you manage your fi nances effi ciently and start working towards your goals sooner, you can spend more in the long run. Besides, ➃ who says spending all your money is the only way to have fun?

➃ Spending all your money is not the only way to have fun.

➂ ➃

➁ This passage from Eric Tyson’s Personal Finances

for Dummies contains an argument. This issue is whether only losers who don’t know how to have a good time save for retirement. The conclusion is that it is not true that only losers who don’t know how to have a good time save for retirement. The fi rst premise is that if you manage your fi nances effi ciently and start working towards your goals sooner, you can spend more in the long run. The second premise is that spending all your money is not the only way to have fun.

12. ➀ A team of engineers found that Hurricane Katrina damaged the structural integrity of the Lake Pontchartrain bridge. Therefore, ➁ the bridge will have to be closed until its safety can be assured.

➀

➁ This passage contains an argument. This issue

is whether the Lake Pontchartrain bridge will have to be closed until its safety can be assured. The conclusion is that the Lake Pontchartrain bridge will have to be closed until its safety can be assured. The premise is that a team of engineers found that Hurricane Katrina damaged the structural integrity of the Lake Pontchartrain bridge.

15. ➀ Some people argue that we should increase for- eign aid to Pakistan. But ➁ this is a terrible idea!

➂ Pakistan is currently too unstable and ➃ their regime is corrupt. Furthermore, ➄ they may use the money to attack neighboring countries like India.

➁ We should not increase foreign aid to Pakistan.

➂ ➃ ➄

➁ This passage contains an argument. The issue

is whether we should increase foreign aid to Pakistan. The conclusion is that we should not increase foreign aid to Pakistan. The fi rst premise is that Pakistan is unstable. The second premise is that Pakistan’s regime is corrupt. The third prem- ise is that Pakistan may use foreign aid to attack neighboring countries like India.

18. This passage contains an argument. The issue is whether money spent on space exploration could be better spent here on Earth. The conclusion is that money spent on space exploration could not be better spent here on Earth. The fi rst premise is that people are natural explorers. The second premise is that space offers the last frontier for us to explore. The third premise is that the technol- ogy that will result from the space program will have many uses in satellite and missile defense systems.

This argument commits the red herring fallacy because the premises given distract the reader from the issue. None of the premises addresses whether the money could be better spent for other projects.

Chapter 6

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This page contains answers for this chapter only

Chapter 5: Detecting Fallacies

Begging the Question
Appeal to Ignorance
Appeal to Illegitimate Authority
Ad Hominem
Strawman
Red Herring
Putting It All Together: A Basic Analysis Plus Fallacy Identifi Cation
Chapter Review Questions

Answers to Selected Exercises

critical thinking_chapter11.pdf

CRITICAL THINKING

A USER’S MANUAL

DEBRA JACKSON & PAUL NEWBERRY California State University, Bakersfi eld

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Causal arguments are the fi nal kind of argument you will learn to evaluate in this book. These arguments and the reasoning they employ are frequently used in solving everyday problems, as well as in scientifi c and legal reasoning. Consider the following example.

In 2000, 17 whales of four different species were stranded on a beach in the Bahamas. Seven of the animals are known to have died, and ten other animals were returned to the water alive. Studies of the dead animals showed some sort

of acoustic, or impulse trauma. Based on the way in which the strandings coincided with ongoing naval activity involving tactical mid-range frequency sonar use in terms of both time and geography and the absence of any other acoustic sources, the investigation team concludes that tactical mid-range frequency sonars aboard U.S. Navy ships that were in use during the sonar exercise were the most plausible source of this acoustic or impulse trauma.—Joint Interim Report, Bahamas Marine Mammal Stranding, Event of 15–16 March 20001

Using the skills you learned in Chapter 6, you can recognize this as an inductive causal argument. The argument uses inductive reasoning because the arguer attempts to show that the truth of the conclusion probably follows from the truth of the premises. More- over, the argument is causal because the conclusion is a causal claim. In this chapter, you will learn how to recognize, analyze, and evaluate causal arguments. Just as with the other two induc- tive arguments you have learned about in this text—analogical arguments and inductive generalizations—you will discover that all causal arguments share a basic underlying structure. After a brief review of how to recognize causal arguments, you will prac- tice analyzing and identifying the core features of these arguments.

C H A P T E R

11 Evaluating Causal Arguments

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Researchers examine a dead whale beached in the Bahamas. Autopsies suggest a possible link between U.S. Navy anti- submarine sonar and ear hemorrhages that disoriented the whale.

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263Recognizing Causal Arguments

Then, you will learn how to determine which causal arguments should convince and which should not.

Recognizing Causal Arguments Because a causal argument is an inductive argument that provides evidence to prove that a causal claim is true, the conclusion of every causal argument will be a causal claim. A causal claim is a statement indicating a causal relationship between one event and another. The following are some examples of causal claims.

The cause of Jacob’s high fever was H1N1. Your sore back is the result of incorrect lifting. Increased regulation of banks will prevent future economic disasters.

Even though these claims differ in content and style, they all are causal. The fi rst claim states that Jacob’s high fever was caused by H1N1. Even though we often speak about causes in this fashion, as if an object can cause something to happen, such language is actually inaccurate and misleading. Causes and effects are not objects, but events. Therefore, the fi rst claim should be understood as expressing the claim that Jacob’s having a high fever was caused by contracting H1N1. The second claim, then, states that your back being sore was caused by lifting incorrectly. In the third claim, the causal relation is stated in terms of one event being prevented by another, yet speaking about prevention is still a way of making a causal claim. So, the third claim indicates that avoiding future economic disasters is caused by increased bank regulation. When you analyze causal arguments, remember that your statement of the causal claim should always be phrased in terms of events.

E X E R C I S E 1 1 . 1

Your Turn! Restate the following causal claim in the form of one event being caused by another event.

Tactical mid-range frequency sonars aboard U.S. Navy ships that were in use during the sonar exercise were the most plausible source of the acoustic or impulse trauma to the injured whales.

E X E R C I S E 1 1 . 2

Determine which of the following are causal claims. Then restate the claim in the form of one event being caused by another event.

1. I have a headache from watching too much television. 2. Too many pesticides will render the water non-potable. 3. Disneyland is the happiest place on Earth. 4. After I painted that foul-tasting polish on my daughter’s fi ngernails, she

stopped biting them.

E XE X E RE R C IC I S ES E 1 11 1 . 2. 2

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264 C H A P T E R 1 1 Evaluating Causal Arguments

To recognize a causal argument, make sure that the argument is inductive, then look for a causal claim in the conclusion. Consider the following.

I failed my Geology midterm. My professor doesn’t like me, so that must be the cause of my failing the test.

Let’s fi rst identify the premises and conclusions using a Formal Analysis.

P1: I failed my Geology midterm. P2: My professor doesn’t like me. ∴ My teacher not liking me caused me to fail the Geology midterm.

Issue: Whether my teacher not liking me caused me to fail the Geology midterm

In this example, even though the conclusion is preceded with that must be the cause, it is possible that the reason I failed the Geology midterm was something besides the professor not liking me. For instance, I might not have studied enough or the test may have been different than I expected. As you may remember from Chapter 6, arguers sometimes deceptively use deductive argument indicators in inductive arguments to make the conclusion appear more certain. So, the argument is an inductive one, since the truth of the premises makes the truth of the conclusion at best only probable, not necessary. Further, you can identify the argument as an inductive causal argument because the conclusion is a causal claim. It states that my failing the Geology test was caused by the teacher’s not liking me. Finally, you can represent the structure of this argument using an argument diagram.

➀ I failed my Geology midterm. ➁ My teacher doesn’t like me, so ➂ that must be the cause of my failing the test.

➀ + ➁

➂

Consider another example of a causal argument, this one from a scientifi c study.

In a recent study, rats that were fed bacon, sausage, cheesecake, frosting, and other fattening foods became compulsive eaters. The high-fat, high-calorie food

5. Most of my professors wear glasses. 6. The root cause of homelessness is poverty. 7. The coffee tastes better after I clean the coffee pot. 8. Cheaper house prices are the result of the record-high loan default rates. 9. The next philosophy class is like the previous philosophy classes. 10. Updating your antivirus software prevented your computer from getting the

latest computer virus.

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265Recognizing Causal Arguments

must have been the cause, since of the three groups of rats in the study, only the ones fed the fattening diet ate compulsively.

Here’s the Formal Analysis of the argument.

P1: In a recent study, rats that were fed bacon, sausage, cheesecake, frosting, and other fattening foods became compulsive eaters.

P2: Of the three groups of rats in the study, only the ones fed the fattening diet ate compulsively.

∴ Being fed high-fat, high-calorie food was the cause of the compulsive eating by the rats in the study.

Issue: Whether being fed high-fat, high-calorie food was the cause of the compulsive eating by the rats in the study

E X E R C I S E 1 1 . 3

Your Turn! Diagram the previous argument.

E X E R C I S E 1 1 . 4

Present a Formal Analysis of each of the following causal arguments. Then diagram the argument.

1. You say you’ve had insomnia the last three nights, and each of those three nights you drank coffee after dinner. It seems likely, then, that the coffee is what kept you awake.

2. I run the mile almost 10 seconds faster than my teammate. Since I do weight training every day and she doesn’t, that is probably the reason I’m faster than she is.

3. The bugs that were eating the spinach in my garden have disappeared. Given that I surrounded my garden with marigolds, the marigolds must have caused the bugs to disappear.

4. Fewer fi sh are being caught in Miller Lake than used to be the case just a year ago. The likely cause is pollution from the nearby sewage treatment plant, which began operations just this last year.

5. Newspaper prices have gone up in Los Angeles, Salt Lake City, and Dallas. Because the common step taken by the major newspapers in all three cities is that they recently negotiated a higher salary package for their reporters and editors, the price increase must be caused by that extra cost to the papers.

6. It’s likely that the clam chowder caused my two friends and I to get sick last night. This is because we all got sick after eating dinner together, and we all ate the clam chowder.

7. My dogs all started scratching yesterday morning. Their itching must be caused by fl eas, since it’s the only thing I can think of that would cause them all to itch so badly.

E X E R C IC S ES 1 1 . 4.

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266 C H A P T E R 1 1 Evaluating Causal Arguments

8. My car’s battery was dead this morning. Since I had a car radio installed yesterday afternoon, the car radio installation must have caused the battery to die.

9. Tax increases last year led to an increased number of scoffl aws, who don’t pay taxes. The IRS reported a higher-than-usual number of people not paying their taxes last year, and this was the fi rst year in a decade that taxes were increased.

10. Most of the small towns in the Owens Valley area have reported that their populations have decreased since the last census. Since seismic activity has been particularly heavy over that decade, it’s likely that people are leaving the area for fear of earthquakes.

Analyzing Causal Arguments You may have noticed a similar pattern in all of the causal arguments you analyzed in the preceding exercise. Each contains two premises supporting a conclusion. We call this causal argument pattern the general form of the argument. Although some causal arguments may appear to be somewhat different from these examples, every causal argument can be analyzed into this general form.

P1: Some (resulting) event occurred. P2: Some (precipitating) event preceded it. ∴ The resulting event was caused by the precipitating event.

Here’s the pattern shown in one of the examples from the previous section.

P1: I failed my Geology midterm. (resulting event) P2: My professor doesn’t like me. (precipitating event) ∴ My failing the Geology midterm (resulting event) was caused by my

teacher not liking me (precipitating event).

In this pattern you can identify the two events that the arguer concludes are causally related. We identify these events as the resulting event and the precipitating event. The resulting event is the event that the arguer knows has occurred, and for which he or she infers the cause. The precipitating event is the event that the arguer knows has occurred prior to the resulting event, and that he or she suspects is the cause of that resulting event.

Resulting event: my failing the Geology midterm Precipitating event: my professor not liking me

Hint! Although it might seem more natural to speak about these events as the effect and the cause, our analysis cannot assume what the argument is trying to prove, namely that one is in fact the cause of the other. For this reason we employ the terms precipitating event and resulting event, rather than cause and effect.

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267Analyzing Causal Arguments

Although all causal arguments will identify a precipitat- ing event among their premises, they can provide evidence that this event is the cause of the resulting event in many differ- ent ways. Nineteenth-century British philosopher John Stuart Mill identifi ed and categorized fi ve different methods of rea- soning in causal arguments, collectively known as Mill’s Meth- ods. Two of the most commonly used of these methods are the method of agreement and the method of difference. When analyzing causal arguments, you should add the identifi cation of the method to your identifi cation of the resulting event and precipitating event.

First consider an example of a causal argument that utilizes the method of agreement.

It’s likely that the clam chowder caused my two friends and I to get sick last night. This is because we all got sick after eating dinner together, and we all ate clam chowder.

Here’s the argument presented in the general form with the resulting event (R) and precipitating event (P) identifi ed.

P1: My two friends and I got sick after eating dinner together last night. (R)

P2: My two friends and I ate clam chowder. (P) ∴ My two friends and I getting sick after eating dinner together last night

(R) was caused by our eating clam chowder (P).

R: my two friends and I being sick last night P: eating clam chowder

Next, you should identify the method the arguer uses to support the causal claim in the conclusion. To do this, consider why the arguer suspects that eating clam chowder is the cause of the sickness. It is not only because it occurred prior to the resulting event, but also because it is an event in common among everyone who experienced the resulting event. This method of causal reasoning is called the method of agreement. We should add the identifi cation of the method to our analysis, as shown.

M: agreement

A second way that arguers may attempt to support a causal claim is by singling out the factor that is different between the occurrence and non-occurrence of the result- ing event. The reasoning here is that whatever factor is different between the times the resulting event happened and the times it did not is likely to be the cause of the resulting event. Let’s look at an example of this method of causal reasoning from the previous exercise.

My car’s battery was dead this morning. Since I had a car radio installed yesterday afternoon, the car radio installation must have caused the battery to die.

Here is the Formal Analysis of the argument with the resulting event and precipitating event identifi ed afterward.

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British philosopher and social reformer, John Stuart Mill (1806–73).

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268 C H A P T E R 1 1 Evaluating Causal Arguments

Knowing the general form of causal arguments can help you identify when causal arguments are presented with subarguments or extra claims. For example, causal arguments often contain subarguments to support the isolation of the precipitating event from other possible causes. Consider this one.

The coffee this morning tasted terrible. It must have been caused by using tap water, since that was the only thing different from the way I usually make coffee. I used the same beans, the same coffee maker, and the same fi lter.

Here is the Formal Analysis of the causal argument with the resulting event, precipitat- ing event, and method of causal reasoning identifi ed.

P1: The coffee this morning tasted terrible. P2: Using tap water was the only thing different from the way I usually make

coffee. ∴ The cause of the terrible tasting coffee must have been using tap water.

Issue: Whether the cause of the terrible tasting coffee must have been using tap water

P1: The car battery was dead this morning. P2: I had a car radio installed yesterday afternoon. ∴ Installing a car radio yesterday afternoon caused the car battery to die.

Issue: Whether installing a car radio yesterday afternoon caused the car battery to die

R: my car’s battery being dead P: installing a car radio

Notice that the premises in this causal argument support the conclusion in a differ- ent manner than in the previous example. Instead of having multiple instances of the resulting event as we saw in the previous argument, only one instance of the resulting event is given. This means that the resulting event is something different, possibly caused by the introduction of the precipitating event. Rather than identifying what all cases of the resulting event have in common this argument identifi es what is differ- ent between the occurrence of the resulting event and times when it doesn’t occur. In this example, the argument identifi es the installation of the car radio as the difference between the occurrence of the resulting event (the car battery being dead) and its non- occurrence (the battery working). This method of causal reasoning is called the method of difference, and you should add it to your analysis.

M: difference

E X E R C I S E 1 1 . 5

Your Turn! State the precipitating event, the resulting event, and the method for all of the arguments in Exercise 11.4. Your Turn! State the precipitating event, the resulting event, and the method for all of the arguments in Exercise 11.4.

. 5

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269Analyzing Causal Arguments

Now, let’s diagram the argument.

➀ The coffee this morning tasted terrible. ➁ It must have been caused by using tap water, since ➂ that was the only thing different from the way I usually make coffee. ➃ I used the same beans, ➄ the same coffee maker, and ➅ the same fi lter.

➁

�➀ ➂

➃ ➅➄

R: the coffee tasting terrible P: brewing the coffee with tap water M: difference

What role does the fourth sentence play in the passage, namely that “I used the same beans, the same coffee maker, and the same fi lter”? It supports the premise that singles out the precipitating event, namely that the tap water is the only difference between the occurrence of the resulting event and its non-occurrence. That means the argument has a subargument. In this case, the fourth sentence in the passage is supporting the second premise in the argument. So, the subargument looks like this.

P1: I used the same beans as usual to make today’s coffee. P2: I used the same coffee maker as usual to make today’s coffee. P3: I used the same fi lter as usual to make today’s coffee. ∴ Using tap water was the only thing different from the way I usually

make coffee.

E X E R C I S E 1 1 . 6

Your Turn! Write out the entire Formal Analysis in the proper order with the issue included.

E X E R C I S E 1 1 . 6. 6

Your Turn! Write out the entire Formal Analysis in the proper order with the issue included.

E X E R C I S E 1 1 . 7

Your Turn! Provide a Formal Analysis and diagram of the causal argument about whales that began this chapter. Then identify the resulting event, precipitating event, and method of causal reasoning.

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270 C H A P T E R 1 1 Evaluating Causal Arguments

First, underline and number each claim given in the argument.

➀ Brushing your teeth after each meal helps prevent cavities. ➁ A study in New Mexico found that 25% of a group of 40 young people who brushed their teeth after each meal had no cavities compared to 10% of the 35 young people who only brushed in the morning and at night. ➂ The only difference between the groups was the number of times they brushed each day.

The fi rst claim is the main conclusion of the argument. Notice that it is a causal claim about teeth brushing preventing cavities, but it’s not a causal claim about the young people actually observed. Instead, it generalizes from that sample group to the target of all young people. Therefore, since the conclusion is a general claim, the argument is an inductive generalization. The information in the claims about the study, claim ➁ and claim ➂, actually imply a conclusion. To diagram the argument, then, you must supply this missing conclusion as claim ➃. It serves as both the conclusion of the subargu- ment and as a premise in the main argument.

➃ Brushing teeth after each meal helped prevent cavities in the young people who took part in this New Mexico study.

Causal arguments are often used in clinical studies in a particular way. Clinical studies conclude that some causal claim is true by conducting experiments involving two groups, an experimental group and a control group. The difference between them is that only the experimen- tal group experiences the precipitating event. When the resulting event occurs more often in the experimental group than in the control group, the researchers con- clude that the two events are causally related. Then, the researchers generalize from the sample (the experimental and control groups) that participated in the study to an appropriate target population. Thus, the causal argument serves only as a subargument supporting an inductive generalization.

Here’s an example of such use of a causal argument.

Brushing your teeth after each meal helps prevent cavities. A study in New Mexico found that 25% of a group of 40 young people who brushed their teeth after each meal had no cavities compared to 10%

of the 35 young people who only brushed in the morning and at night. The only difference between the groups was the number of times they brushed each day.

D or

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E X E R C I S E 1 1 . 8

Your Turn! Identify the experimental group and the control group in this clinical study.

What messages does this digital illustration convey?

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271Analyzing Causal Arguments

➁ + ➂

➃

➀

Here is the entire argument set out in a Formal Analysis.

P1: A study in New Mexico found that 25% of a group of 40 young people who brushed their teeth after each meal had no cavities compared to 10% of the 35 young people who only brushed in the morning and at night.

P2: The only difference between the two groups was the number of times they brushed each day.

∴ Brushing teeth after each meal helps prevent cavities in the young people who took part in the study in New Mexico.

P: Brushing teeth after each meal helps prevent cavities in the young people who took part in the study in New Mexico.

∴ Brushing your teeth after each meal helps prevent cavities.

Issue: Whether brushing your teeth after each meal helps prevent cavities

From the Formal Analysis of the subargument, we can identify the resulting event, the precipitating event, and the method of reasoning used in the argument.

R: having fewer cavities P: brushing teeth M: difference

You can recognize this causal argument as a clinical study because of two things: First, it has two groups that illustrate the precipitating event and the non-occurrence of that event. Also, the causal claim in the conclusion is a general claim. That is, the research- ers generalized from the two groups of young people (the sample) to the entire group of people (the target).

Hint! Clinical studies are chain arguments consisting of two different inductive arguments. The main one is an inductive generalization, and the subargument is causal. When you evaluate these arguments, you do so as you would any chain argument, by evaluating the main argument only. Thus, in the case of clinical studies, you evaluate the inductive generalization. (See Chapter 10.)

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272 C H A P T E R 1 1 Evaluating Causal Arguments

E X E R C I S E 1 1 . 9

Provide a Formal Analysis and diagram of each of the following passages. Then, identify the resulting event, precipitating event, and method of reasoning.

1. An inadequate job of soil compaction for the Rancho Estates housing development must be causing the cracking of the concrete sidewalks and driveways. This is because the sidewalks and driveways have started cracking in Rancho Estates, and compacting of the soil is the only difference between the work done there and that done in the nearby Prairie View development, where no cracking occurred. The concrete work for both developments was performed by the same contractor.

2. Beginning this week, my sister started sneezing the minute she walked in my door. Given that the only thing that is different in my apartment is that I got a kitten, she must be allergic to the cat. I don’t have any fl owers in the house, the house is not dustier than usual, and I don’t use air fresheners or other deodorizers.

3. Traffi c is heavier on Milton Avenue since the beginning of the month. Since the road department fi nished widening the road right about that time, it’s probably responsible for the extra traffi c.

4. My three siblings and I are all adopted, and yet we all are unusually meticulous about keeping our apartments clean and extremely tidy. Given that we were all raised in the same household, we must have learned that behavior from observing our adoptive parents, who were also very meticulous and tidy.

5. An outbreak of salmonella poisoning occurred at the hospital. It must have been caused by eating eggs from a shipment that had gone bad because the only thing the patients had in common was eating custard pudding (which has eggs in it) for dessert. One of the patients had tuna salad, another had soup, and the third had meat loaf and mashed potatoes.

6. In three major metropolitan areas in the Northeast, mandatory waiting periods for handgun purchases were signed into law last year. Since then, homicide rates dropped by an average of 15%. It is reasonable to conclude that waiting periods for handgun purchases reduce homicides.

7. People who have big smiles live longer. Researchers examined the smiles from photos of 230 baseball players who began playing professional baseball prior to 1950. The smiles were rated for intensity, and then compared with data from deaths that occurred between 2006 and 2009. Some players lived an average of 72.9 years while others lived an average of 79.9 years. Given that the only thing that differentiates those players who lived longer from those who did not is their smiles, their longer lives must have been caused by their larger smiles.—Psychological Science

8. HIV is thought to have evolved from a simian virus found in African chimpanzees in the early 1930s. However, the virus spread very slowly until the middle of the 1950s, when it began to spread rapidly. One important change took place about that time, namely the smallpox vaccine was withdrawn. It could have been helping to prevent the spread of the virus.

9. That old Native American cure for poison oak—covering the blistered area in a paste made from soaked and cooked acorns—is clearly effective. While hiking

. 9

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273Evaluating Causal Arguments

yesterday, you brushed up against some poison oak, and your blisters have shrunk considerably since you began putting on the acorn paste.

10. Since Alex Rodriguez was sidelined two weeks ago with a sprained ankle, the Yankees have fallen from fi rst place, losing fi ve of their last eight games. The only difference in the lineup is Rodriguez. They have the same exact infi eld and outfi eld from the previous month when they were winning 60% of their games. Also, the pitchers are all healthy and rotating as usual. This just shows that Rodriguez is the one who makes the Yankees win.

Hint! Many of the causal arguments you encounter in your life involve multiple precipitating events that serve as contributing factors to the resulting event or situations in which the full range of contributing causes is unknown. In this chapter’s exercises, you do not need to distinguish between precipitating events that may produce a particular resulting event on their own and those which are only part of a more complex causal process.

Evaluating Causal Arguments Since causal arguments are inductive, they are evaluated using the terms appropriate to inductive arguments. As you remember, an inductive argument is strong when its prem- ises, if true, would probably make the conclusion true. So, judgments about a causal argument’s structure will be made in terms of the argument’s strength.

To determine whether or not a causal argument is strong, you must focus on how well the arguer demonstrates that the precipitating event is the only reasonable cause of the resulting event. For causal arguments that utilize the method of agreement, this means that you will evaluate the evidence that the precipitating event is the only common event that could cause the resulting event. And, for causal arguments that uti- lize the method of difference, you will evaluate the evidence that the precipitating event is the only different event that could cause the resulting event.

When an arguer presents a causal argument without offering any evidence that the precipitating event is the only reasonable cause of the resulting event, the argument is known as a post hoc ergo propter hoc (post hoc, for short) argument. The name is Latin for “after this, therefore, because of this.” The mistake in this case is that the arguer concludes that one event was caused by another simply because one preceded the other. However, without considering whether the order of events is simply coinci- dence, whether both resulting and precipitating events are a result of some other event, or whether there is another event that could be more reasonably considered the cause, the arguer has unjustifi ably jumped to a conclusion.

Here is an example of a post hoc causal argument.

The coffee this morning tasted terrible. It must have been caused by using tap water, since that was different from the way I usually make coffee.

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274 C H A P T E R 1 1 Evaluating Causal Arguments

To evaluate this argument, fi rst analyze it.

P1: The coffee this morning tasted terrible. P2: Using tap water was different from the way I usually make coffee. ∴ The cause of this morning’s coffee tasting terrible must have been using

tap water.

Issue: Whether the cause of this morning’s coffee tasting terrible must have been using tap water

R: the coffee tasting terrible P: brewing the coffee with tap water M: difference

Of course, it is logically possible that using tap water to make coffee causes the coffee to taste terrible. Notice, however, that the arguer neither claims nor provides evidence that using tap water is the only reasonable cause of the bad taste. Instead, he or she only shows that one event preceded the other. Perhaps the bad taste is a result of using stale coffee beans, or a dirty coffee pot, or drinking from a plastic cup that has affected the fl avor of the coffee. Without any evidence that the two events are causally related, the arguer has not given us good reasons to accept the conclusion that the coffee tasting terrible is caused by brewing the coffee with tap water.

Let’s now look at a better version of that argument.

The coffee this morning tasted terrible. It must have been caused by using tap water, since that was the only difference from the way I usually make coffee.

Again, the fi rst step is a Formal Analysis.

P1: The coffee this morning tasted terrible. P2: Using tap water was the only difference from the way I usually make coffee. ∴ The cause of this morning’s coffee tasting terrible must have been using

tap water.

Issue: Whether the cause of this morning’s coffee tasting terrible must have been using tap water

R: the coffee tasting terrible P: brewing the coffee with tap water M: difference

Notice that what has changed in this version of the argument is the second premise. In the post hoc version, the arguer identifi es using tap water as a difference from the way he or she usually makes coffee, whereas in the second version identifi es using tap water as the only difference from the way he or she usually makes coffee. This second argument is stronger than the previous one, because if the premises were true—that the coffee tasted terrible and that the tap water was the only thing different—then the conclusion is likely to be true.

Finally, let’s consider an even stronger version of the argument. This one does not simply assert that the only difference is that tap water was used to make the coffee, but it also contains a subargument with premises to support that claim.

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275Evaluating Causal Arguments

The coffee this morning tasted terrible. It must have been caused by using tap water, since that was the only difference from the way I usually make coffee. I used the same beans, the same coffee maker, and the same fi lter.

Here’s the Formal Analysis.

P1: I used the same beans as usual to make today’s coffee. P2: I used the same coffee maker as usual to make today’s coffee. P3: I used the same fi lter as usual to make today’s coffee. ∴ Tap water was the only difference from the way I usually make coffee.

P1: The coffee this morning tasted terrible. P2: Using tap water was the only difference from the way I usually make coffee. ∴ The cause of the terrible tasting coffee must have been using tap water.

Issue: Whether the cause of the terrible tasting coffee must have been using tap water

R: the coffee tasting terrible P: brewing the coffee with tap water M: difference

Notice that this analysis begins with the subargument that provides evidence for the claim that using the tap water was the only difference between this morning’s coffee and that of other mornings. This evidence rules out three other possible precipitating events, any one of which could reasonably be considered the cause of the resulting event. Since this third version of the argument provides evidence supporting the causal connection between the precipitating event and the resulting event, it is stronger than both of the previous arguments.

E X E R C I S E 1 1 . 1 0

For each of the following pairs of causal arguments, determine which version of the argument, A or B, is stronger. Briefl y explain why.

1. A. Your pack has a huge hole in it. It must be the scissors that caused it, since they are the only sharp things inside.

B. Your pack has a huge hole in it. It must be the scissors that caused it, since they are sharp.

2. A. The pizzas from Big John’s have always been hot when they are delivered. However, the last two times they were barely warm when we got them. The new driver must not know his way around town.

B. The pizzas from Big John’s have always been hot when they are delivered. However, the last two times they were barely warm when we got them. The only thing different is that they have a new driver, and he must not know his way around town. I was in the restaurant the other day and they certainly aren’t busier than usual.

E X E R C IC S ES 1 1 . 1. 00

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276 C H A P T E R 1 1 Evaluating Causal Arguments

3. A. Four of the swimmers avoided the fl u that was going around this summer. All four had the fl u shots given out by the campus clinic, and that was the only preventative step they had in common. Three had been exposed to someone who was sick, two of them took vitamin C but the other two didn’t, and only one of them eats a healthy diet.

B. Four of the swimmers avoided the fl u that was going around this summer. All four had the fl u shots given out by the campus clinic, and that was the only preventative step they had in common.

4. A. Why did I do so badly on the midterm? The answer is simple. Yesterday I broke a mirror and that means seven years of bad luck. So it’s obvious that my poor grade resulted from that broken mirror.

B. Why did I do so badly on the midterm? The answer is simple. Yesterday I broke a mirror and that means seven years of bad luck. I studied just as hard as the previous exam, got a good night’s sleep, and thought I really knew the material. So it’s obvious that my poor grade resulted from that broken mirror.

5. A. Many people reported seeing fl ashing lights in the sky last night. Apparently, the sightings were caused by the car lot grand opening, since the only possible difference was that the business was shining search lights all night long. No airport is nearby, no fi reworks were set off, and we’re too far south for the Aurora Borealis.

B. Many people reported seeing fl ashing lights in the sky last night. Apparently, the sightings were caused by the car lot grand opening, since the business was shining search lights all night long.

6. A. Did you hear that Simon left American Idol? Advertisers were complaining about his nasty comments, and that must be the cause of his dismissal.

B. Did you hear that Simon left American Idol? The only plausible cause is that advertisers were complaining about his nasty comments, so that must be the cause of his dismissal.

7. A. India has experienced below-normal rainfall during the monsoon season for the last three years. Each time, the surface temperature of the Pacifi c Ocean off the coast of Latin America has been warmer than usual. Thus, the warmer ocean water off Latin America probably caused those occasions of below-normal rainfall in India during the monsoon season.

B. India has experienced below-normal rainfall during the monsoon season for the last three years. Each time, the only relevant common characteristic is that the surface temperature of the Pacifi c Ocean off the coast of Latin America has been warmer than usual. Thus, the warmer ocean water off Latin America probably caused those occasions of below-normal rainfall in India during the monsoon season.

8. A. The residence hall suffered a serious fi re last night. During the investigation of the tragedy, detectives found a short in the electrical system. Therefore, the fi re was probably caused by a short in the new electrical system. The investigation ruled out other possible causes. There was no sign of arson, the heater was working fi ne, and smoking is not allowed in the building.

B. The residence hall suffered a serious fi re last night. During the investigation of the tragedy, detectives found a short in the electrical system. Therefore, the fi re was probably caused by a short in the new electrical system. The investigation ruled out other possible causes.

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277Evaluating Causal Arguments

E X E R C I S E 1 1 . 1 1

For each of the following causal arguments, determine whether the revised argument is stronger, weaker, or neither stronger nor weaker than the original. Briefl y explain why.

1. Three members of the golf team have set personal records during the last month. Each of them has been spending extra hours at the putting green this month, so the extra work is likely to be the cause of their improved performances. a. Suppose each member had begun working out at the weight room this

month, too. b. Suppose that only two of the members had been spending extra hours at

the putting green this month. c. Suppose the extra hours at the putting green are the only common

precipitating event for the three of them. d. Suppose that each of the members of the golf team has a different coach.

2. My younger brothers recently realized they could actually remember a couple of events that happened before they were born. Both of them were recently hypnotized, so that must be the cause of their new-found memories. a. Suppose being hypnotized is the only thing that has recently happened to

both of them. b. Suppose that they both also underwent psychoanalysis. c. Suppose that false memories, psychoanalysis, and hallucinations were all

ruled out as possible precipitating events. d. Suppose they each recently started learning French.

3. My car’s battery was dead this morning. Since the only difference from when the battery was fi ne was having a car radio installed yesterday afternoon, the car radio installation must have caused the battery to die. a. Suppose it rained today but yesterday it was sunny. b. Suppose the interior lights were not left on last night.

9. A. Several children have recently visited the clinic complaining of severe headaches. They all live in apartments with chipped lead paint on the walls. We believe that the lead paint is causing their headaches.

B. Several children have recently visited the clinic complaining of severe headaches. The only commonality with them is that they all live in apartments with chipped lead paint on the walls. We believe that the lead paint is causing their headaches.

10. A. Johnson won the sales award two times in the past year. The only event that preceded each of his wins was attending a seminar on promoting teamwork—otherwise, he had contacted his usual clients and done his usual follow-up calls. Apparently, these seminars work.

B. Johnson won the sales award two times in the past year. The only event that preceded each of his wins was attending a seminar on promoting teamwork—otherwise, he had contacted his usual clients, attended the usual sales meetings, and done his usual follow-up calls. Apparently, these seminars work.

E X E R C I S E 1 1 . 1 1

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278 C H A P T E R 1 1 Evaluating Causal Arguments

Putting It All Together: A Complete Analysis Plus Evaluation

With the completion of this chapter, you have learned to recognize, analyze, and evalu- ate the structure of fi ve different kinds of arguments, as well as detect arguments that commit fallacies. Let’s now put this into a Complete Analysis Plus Evaluation.

c. Suppose the car also had a new alternator installed yesterday. d. Suppose the car also had a new alternator installed two weeks ago.

4. It’s likely that the clam chowder caused my two friends and I to get sick last night. This is because we all got sick after eating dinner together, and we all ate clam chowder. a. Suppose the only food we ate in common was the clam chowder. b. Suppose we all had different beverages with our meals. c. Suppose that before we went to dinner, we visited a friend in the hospital. d. Suppose we all used the same salt shaker to fl avor our clam chowder.

5. Last year the county saw a reduction of 24% in the amount of solid waste material that was put into the county landfi ll. This means that the curbside recycling program, just instituted this year, is working. a. Suppose in the past 10 months the county reduced garbage pickup to one

can per week. b. Suppose the county no longer accepts solid waste material from

neighboring counties. c. Suppose that the population of the county has decreased by 10%. d. Suppose the population of the county has remained stable over the

past year.

Directions for a Complete Analysis Plus Evaluation

In paragraph form, use complete sentences and proper English grammar and spelling to do the following:

Step 1: Write a Basic Analysis of the passage. (You may want to refer to the Directions for Basic Analysis, Chapter 3, page 49).

Step 3: If the argument does not commit a fallacy, diagram it and verify that the diagram is consistent with your Basic Analysis.

Step 4: In a separate paragraph, identify the kind of argument. ▲ If the argument is deductive, identify it as a categorical argument or a truth-

functional argument. ▲ If the argument is inductive, identify it is an analogical argument, an

inductive generalization, or a causal argument.

Putting It All Together: A Complete Analysis Plus Evaluation

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279Putting It All Together: A Complete Analysis Plus Evaluation

Here are some samples of a Complete Analysis plus Evaluation for a causal argu- ment. After seeing how these are done, you will try some on your own.

Wolf populations in the mountains of the western United States have increased in the last two decades. This result is most likely caused by the two decades of prohibition against hunting wolves, since that is the only signifi cant difference between conditions now and conditions prior to the last two decades.

First, identify the passage as an argument, explanation, or neither. This passage is an argument because it is trying to convince the reader that the wolf population increase was caused by the restrictions on hunting. Does it commit a fallacy? It does not. Since the phrase is most likely indicates that the argument utilizes inductive reasoning and the conclusion is a causal claim, we can recognize the argument as an inductive causal argument. Thus, we will analyze and evaluate the argument in this manner.

➀ Wolf populations in the mountains of the western United States have increased in the last two decades. ➁ This result is most likely caused by the two decades of prohibition against hunting wolves , since ➂ that is the only signifi cant difference between conditions now and conditions prior to the last two decades.

➀ + ➂

➁

This passage contains an argument. The issue is whether the increased populations of wolves in the western United States are caused by the two decades of prohibition against hunting wolves. The conclusion is that the

Step 5: Evaluate the argument. ▲ If the argument is categorical, state the syllogism in standard form, and

demonstrate whether the argument is valid or invalid using either a Venn diagram or the rules for valid syllogisms.

▲ If the argument is truth-functional, translate the argument, and demonstrate whether the argument is valid or invalid by identifying the argument form, using the truth table method, or using the shortcut method.

▲ If the argument is analogical, evaluate its strength by considering the evidence provided for the analogy and the relevance of the analogy to the feature.

▲ If the argument is an inductive generalization, then evaluate its strength by considering sample randomness and sample size.

▲ If the argument is a causal argument, evaluate its strength by considering the evidence that the precipitating event is the only reasonable cause of the resulting effect.

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280 C H A P T E R 1 1 Evaluating Causal Arguments

increased populations of wolves in the western United States are caused by the two decades of prohibition against hunting wolves. The premises are that wolf populations in the mountains of the western United States have increased in the last two decades, and that the prohibition against hunting is the only signifi cant difference between conditions now and conditions prior to the last two decades.

This argument is an inductive causal argument. It is a fairly strong argu- ment because it states that the ban on hunting is the only reasonable cause of the increased wolf population.

Let’s consider another example, this time one that is a clinical study.

In a university study, 42 college students described themselves as regular binge drinkers and 53 students stated that they do not drink alcohol regularly. Of these, the binge drinkers performed signifi cantly worse on a memory test while sober. For men, binge drinking is defi ned as having fi ve or more alcoholic drinks during a two-hour period. For women, that number is four or more in that period of time. Researchers concluded that binge drinking may impair the brains of binge drinkers even when they are not drinking.—Alcoholism: Clinical and Experimental Research

The fi nal sentence of the passage is the conclusion, with the other claims intending to convince the reader of the truth of the conclusion. Thus, the passage is an argument. Does it commit a fallacy? It does not. Since the conclusion is not about the causal effects on the college students in the study, but rather the target (all people) of which the college students are a sample, this is a clinical study; the main argument will be an inductive generalization whereas the causal argument is a subargument. Here is the analysis and evaluation.

➀ In a university study, 42 college students described themselves as regular binge drinkers and 53 students stated that they do not drink alcohol regularly. ➁ Of these, the binge drinkers performed signifi cantly worse on a memory test while sober. ➂ For men, binge drinking is defi ned as having fi ve or more alcoholic drinks during a two-hour period. ➃ For women, that number is four or more in that period of time. Researchers concluded that ➄ binge drinking may impair the brains of binge drinkers even when they are not drinking. ➅ Binge drinking impaired the brains of the 42 students in the study who described themselves as regular binge drinkers.

➀ + ➁

➅

➄

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281Putting It All Together: A Complete Analysis Plus Evaluation

E X E R C I S E 1 1 . 1 2

Write a Complete Analysis plus Evaluation for the following passages.

1. A recent study suggests that depression causes employees to have problems at work. Researchers compared 286 depressed workers with 193 others who were not depressed. Since only the depressed workers had such problems as fatigue, lack of motivation, and trouble managing their usual workload, researchers concluded that depression was the cause of their problems at work.—American Journal of Health Promotion

2. If the demands of justice can be assessed only with the help of public reasoning, and if public reasoning is constitutively related to the idea of democracy, then there is an intimate connection between justice and democracy.—Amartya Sen, The Idea of Justice

3. Shows like Survivor are alluring precisely because they mirror the ancient struggles within our minds and among our peers.—Christakis and Fowler, Connected

4. Since many art majors are creative artists, and no creative artists need to learn the history of art, it makes sense that not all art majors need to learn the history of art.

5. Middle-aged and older women who have migraines and who experience auras (e.g., fl ashing lights that might signal the onset of pain) appear to have a higher risk of strokes and heart attacks than their migraine-free

This passage from Alcoholism: Clinical and Experimental Research contains an argument. The issue is whether binge drinking may impair the brains of binge drinkers even when they are not drinking. The conclusion is that binge drinking may impair the brains of binge drinkers even when they are not drinking. The premise is that binge drinking impaired the brains of the 42 students in the study who described themselves as regular binge drinkers.

This argument contains a subargument. The intermediate conclusion is that binge drinking impaired the brains of the 42 students in the study who described themselves as regular binge drinkers. The fi rst premise is that 42 college students described themselves as regular binge drinkers and 53 students stated that they do not drink alcohol regularly. The second prem- ise is that the binge drinkers performed signifi cantly worse on a memory test while sober than the non-drinkers.

The main argument is an inductive generalization. The argument is somewhat strong, since the sample size of 95 students is reasonably large. The argument does not identify how the participants were selected or their gender percentages, thus we cannot determine whether the sample was random.

Notice that the causal argument is not evaluated because it is not the main argument. Also, claims ➂ and ➃—defi ning what is meant by binge drinking for men and for women—are extra claims, and so are not included in the analysis. This is because these claims are neither premises nor conclusions; they only clarify what qualifi es as binge drinking.

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282 C H A P T E R 1 1 Evaluating Causal Arguments

peers, a new study suggests. The study looked at 27,798 female health professionals ages 45 and older, including 3,568 who had migraines. It showed that women with weekly migraines with auras were four times as likely to have had a stroke during the 12-year study as women without migraines.—Neurology

6. Many bloggers have argued recently that obesity is a major cause of premature death. But no one can live forever. Therefore, we needn’t be bothered about whether obesity is a major cause of premature death.

7. Our team lost the game last night, and I have fi gured out the cause. I didn’t wear my lucky socks.

8. The lawmakers in this country clearly are not interested in protecting our children from harmful advertising on television. I say this because if they were interested in protecting children, then legislation limiting advertising aimed at children would be enacted into law, and that just isn’t going to happen. Why not? Because advertising lobbyists have been spending freely to persuade your government representatives to kill the legislation.

9. Because in India girls traditionally do not receive an inheritance on the death of their parents, the dowry is considered an “up front” payment of a potential inheritance.—John Weeks, Population: An Introduction to Concepts and Issues

10. If mine safety is really important to the people in this country, then they would be putting constant pressure on their elected offi cials to strengthen the power of regulatory agencies to close down mines with serious safety infractions. Since this doesn’t seem to be happening, people must not be very concerned about mine safety.

11. When I went hiking last weekend, I saw hundreds of dead bees lying on the trails. I bet they died from PFOA or perfl uorooctanoic acid poisoning, since a new plastics manufacturing plant was built upwind last year.

12. The “two meals for the price of one” program we tried out in two of our restaurants this spring has been a huge success. Therefore, this is bound to be a great success when we launch the program for all restaurants this fall.

13. Did you realize that teaching in college is quite similar to teaching in high school? Teachers in college face many of the same problems with students who learn in different ways as do teachers in high school. So, since high school teachers benefi t from learning a variety of teaching strategies to reach students who learn in different ways, college teachers likewise would benefi t from learning a variety of teaching strategies, too.

14. If there ever was in the history of humanity an enemy who was truly universal, an enemy whose acts and moves trouble the entire world, threaten the entire world, attack the entire world in any way or another, that real and really universal enemy is precisely Yankee imperialism.—Fidel Castro

15. Rising unemployment is resulting in a crime wave in our county. The police department reported that violent crime has risen 6% since last year, whereas property crimes are up nearly 12%. The only thing different is that unemployment is up by two full percentage points over last year.

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283Chapter Review Questions

Chapter Review Questions

1. How can you recognize that an argument is a causal argument? 2. What is a causal claim? 3. What is the difference between a precipitating event and a resulting event? 4. What are the two methods of causal reasoning described in this chapter? 5. How does a clinical study utilize causal reasoning? 6. What terms are used for evaluating inductive arguments? 7. What goes wrong in a “post hoc ergo propter hoc” causal argument? 8. How do you determine whether a causal argument is strong?

Chapter Re ie Q estions

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332 A N S W E R S T O S E L E C T E D E X E R C I S E S

Chapter 11

E X E R C I S E 1 1 . 2

3. Not a causal claim. 6. Causal claim. Being homeless is caused by being

poor. 9. Not a causal claim.

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This page contains answers for this chapter only

333A N S W E R S T O S E L E C T E D E X E R C I S E S

E X E R C I S E 1 1 . 4

3. P1: The bugs that were eating the spinach in my garden have disappeared.

P2: I surrounded my garden with marigolds. ∴ The bugs disappearing was caused by my

surrounding my garden with marigolds.

Issue: Whether the bugs disappearing was caused by my surrounding my garden with marigolds

➀ The bugs that were eating the spinach in my garden have disappeared. Given that ➁ I sur- rounded my garden with marigolds, ➂ the mari- golds must have caused the bugs to disappear.

➀ +➁

➂ 6. P1: My two friends and I got sick after eating din-

ner together. P2: My two friends and I ate the clam chowder. ∴ My two friends and I getting sick last night was

caused by our eating the clam chowder.

Issue: Whether my two friends and I getting sick last night was caused by our eating the clam chowder

It’s likely that ➀ the clam chowder caused my two friends and I to get sick last night. This is because ➁ we all got sick after eating dinner together, and ➂ we all ate the clam chowder.

➁ +➂

➀ 9. P1: The IRS reported a higher-than-usual number

of people not paying their taxes last year. P2: Last year was the fi rst year in a decade that

taxes were increased. ∴ An increased number of scoffl aws who don’t

pay taxes was caused by taxes being increased last year.

Issue: Whether an increased number of scoffl aws who don’t pay taxes was caused by taxes being increased last year

➀ Tax increases last year led to an increased number of scoffl aws, who don’t pay taxes. ➁ The IRS reported a higher-than-usual number of people not paying their taxes last year, and ➂ this was the fi rst year in a decade that taxes were increased.

➁ +➂

➀

E X E R C I S E 1 1 . 9

3. P1: Traffi c is heavier on Milton Avenue since the beginning of the month.

P2: The road department fi nished widening Milton Avenue at the beginning of the month.

∴ The road being widened caused the traffi c to become heavier on Milton Avenue.

Issue: Whether the road being widened caused the traffi c to become heavier on Milton Avenue

R: the traffi c becoming heavier on Milton Avenue

P: the road being widened M: difference

➀ Traffi c is heavier on Milton Avenue since the beginning of the month. Since ➁ the road depart- ment fi nished widening the road right about that time, ➂ it’s probably responsible for the extra traffi c.

➀ +➁

➂

6. P1: In three major metropolitan areas in the North- east, mandatory waiting periods for handgun purchases were signed into law last year.

P2: Homicide rates in three major metropolitan areas in the Northeast dropped by an average of 15% last year.

∴ The homicide rates in three major metropolitan areas in the Northeast dropping by an average of 15% was caused by mandatory waiting periods for handgun purchases being signed into law.

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334 A N S W E R S T O S E L E C T E D E X E R C I S E S

P: The homicide rates in three major metropolitan areas in the Northeast dropping by an average of 15% was caused by mandatory waiting periods for handgun purchases being signed into law.

∴ Waiting periods for handgun purchases reduce homicides in any city.

Issue: Whether waiting periods for handgun purchases reduce homicides in any city

R: the homicide rates in three major metropolitan areas in the Northeast dropping by an average of 15% last year

P: mandatory waiting periods for handgun pur- chases were signed into law last year in three major metropolitan areas in the Northeast

M: difference

➀ In three major metropolitan areas in the North- east, mandatory waiting periods for handgun purchases were signed into law last year. ➁ Since then, homicide rates dropped by an average of 15%. It is reasonable to conclude that ➂ waiting periods for handgun purchases reduce homicides.

➃ The homicide rates in three major metropolitan areas in the Northeast dropping by an average of 15% was caused by mandatory waiting periods for handgun purchases being signed into law.

➀ +➁

➃

➂ 9. P1: While hiking yesterday, you brushed up against

some poison oak. P2: Your blisters have shrunk considerably since

you began putting on the acorn paste. ∴ Your blisters shrinking was caused by using

acorn paste.

P: Your blisters shrinking was caused by using acorn paste.

∴ Covering the blistered area in a paste made from soaked and cooked acorns is an effective treat- ment for poison oak.

Issue: Whether covering the blistered area in a paste made from soaked and cooked acorns is an effective treatment for poison oak

R: your blisters shrinking P: using acorn paste M: difference

➀ That old Native American cure for poison oak— covering the blistered area in a paste made from soaked and cooked acorns—is clearly effective. ➁ While hiking yesterday, you brushed up against some poison oak, and ➂ your blisters have shrunk considerably since you began putting on the acorn paste.

➃ Your blisters shrinking was caused by using acorn paste.

➁ +➂

➃

➀

E X E R C I S E 1 1 . 1 0

3. A: it provides evidence that the fl u shots were the only possible cause.

6. B: it states that advertisers’ complaints are the only possible cause.

9. B: it states that chipped lead paint is the only pos- sible cause.

E X E R C I S E 1 1 . 1 1

3. a. weaker because another difference is introduced b. stronger because it provides evidence that the

installation is the only difference c. weaker because another difference is introduced d. no change because the new difference is not a

reasonable cause of the resulting event

E X E R C I S E 1 1 . 1 2

3. This passage from Christakis and Fowler’s Connected contains an explanation. The explanandum is that

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335A N S W E R S T O S E L E C T E D E X E R C I S E S

shows like Survivor are alluring. The explanans is that shows like Survivor mirror the ancient struggles within our minds and among our peers.

6. This passage contains an argument. The issue is whether obesity is a major cause of premature death. The conclusion is that obesity is not a major cause of premature death. The premise is that no one can live forever.

The argument commits the red herring fallacy because the premise distracts the reader from the issue.

9. This passage from John Weeks’s Population: An Introduction to Concepts and Issues contains an explanation. The explanandum is that in India, the dowry is in essence an “up front” payment of a potential inheritance. The explanans is that Indian girls traditionally do not receive an inheritance on the death of their parents.

12. ➀ The “two meals for the price of one” program we tried out in two of our restaurants this spring has been a huge success. Therefore, ➁ this is bound to be a great success when we launch the program for all restaurants this fall.

➀

➁ This passage contains an argument. The issue is

whether the “two meals for the price of one” pro- gram will be a great success when we launch the program for all restaurants this fall. The conclusion is that the “two meals for the price of one” pro- gram will be a great success when we launch the program for all restaurants this fall. The premise is that the “two meals for the price of one” program

we tried out in two of our restaurants this spring has been a huge success.

The argument is an inductive generalization. It is weak because the sample size is very small.

15. ➀ Rising unemployment is resulting in a crime wave in our county. ➁ The police department reported that violent crime has risen 6% since last year, whereas property crimes are up nearly 12%. ➂ The only thing different is that unemployment is up by two full percentage points over last year.

➁ +➂

➀ This passage contains an argument. The issue

is whether rising unemployment is resulting in a crime wave in our county. The conclusion is that rising unemployment is resulting in a crime wave in our county. The fi rst premise is that the police department reported that violent crime has risen 6% since last year, whereas property crimes are up nearly 12%. The second premise is that the only thing different is that unemployment is up by two full percentage points over last year.

This argument is an inductive causal argument. It is somewhat strong because it identifi es the precipitating event as the only difference that could cause the resulting event.

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This page contains answers for this chapter only

Chapter 11: Evaluating Causal Arguments

Recognizing Causal Arguments
Analyzing Causal Arguments
Evaluating Causal Arguments
Putting It All Together: A Complete Analysis Plus Evaluation
Chapter Review Questions

Answers to Selected Exercises

fallacies_of_assumption.pdf

Fallacies of Assumption:

Fallacies of Assumption present a problem of insufficient evidence and make it impossible to determine a legitimate degree of probability. Specific fallacies of assumption include:

1. Overgeneralization (also known as False Generalization or Hasty Generalization)

An overgeneralization occurs when one makes a general claim about something without having the proper information to do so or when it is impossible to do so.

Example: I recently visited the country of X for 2 days. All the citizens of X are very impolite.

From visiting a country for a few days, it is not probable that there is enough of a sample set in the evidence to make this conclusion. All generalization carries this risk. Stereotyping is a common form of hasty generalization. Both stereotyping and the example above illustrate the danger of generalization based on insufficient evidence since it is not likely that all possible cases/people have been observed. One observation that differs can negate the credibility of the conclusion.

Some generalizations can be used effectively when conclusions are drawn from evidence that includes knowledge of the entire sample group. For instance, it is fairly safe to make generalizations of a family when one has met all the family members. And it may also be fairly safe when the sample group does not contain all but properly reflects the entire population discussed. For instance, polls on who will vote for whom where in which the sample group represents the overall population in terms of age, gender, religion, etc. Another generalization that can be fairly safe is a generalization about something that is part of the essence of the thing. For instance, all humans can use language.

2. Card stacking Card Stacking is a fallacy that occurs when one changes evidence or even does not disclose evidence that negatively affects one’s case. This would partly relate to the idea of not considering opposing viewpoints and counterexamples. An example of this might be the realtor that rushes you through a closing without revealing a termite infestation in the house. 3. Ad ignorantium (also known as Appeal to Ignorance or Arguments from Ignorance) Appeal to ignorance demonstrates faulty reasoning by claiming that if something is unknown, unproven, or not yet agreed upon, then it is implied that it is also unknowable or improvable or false. Just because something has not yet been proven true does not imply it is false. Example: No one has ever produced an extra terrestrial being, therefore aliens do not exist. Arguments from ignorance are not about whether the person making the argument is knowledgeable on the topic they are addressing, but rather when an argument from ignorance tries to prove something from a lack of evidence as in the above example.

4. Post hoc ergo propter hoc (also known as False Causation) A post hoc fallacy claims one thing causes another when there is some sort of correlation. However, these conclusions are normally drawn after the fact and the two things may have occurred sequentially, but are not in a relation of causation. Example: Every time I eat cereal in the morning, the Cubs win. Therefore, if I eat cereal this morning, the Cubs will win. Notice: This example claims that cereal-eating causes the Cubs to win. The two are correlated (when one happens, the other does as well), but is there a relation of causation? The above example is fallacious because there is no relevance between cereal eating and the Cubs winning. Irrelevance is one of five variations of the fallacy of false causation that we will look at. The other four include: 1. Reverse Causation – The claim is that x causes y and really y causes x. Example: Every time I sneeze, I get a cold 2. Omission of External Cause – The claim is that x causes y, but really both x and y are caused by a third thing z. Example: Mr. X is handsome because he is smart. (Mr. X’s genes caused both.) 3. Omission of Intermediate Cause – The claims is that x causes z not realizing that between x and z lays another cause y. Example: If a person surfs the internet, it causes the computer to shut off. (The intervening third cause is that the battery of the lap top runs out.) 4. Omission of Timing/Extent of cause – The claim is that x causes y, but one cannot project beyond this case. Example: When it rains, flowers grow. Therefore, the more rain the better the flowers are…. (But if it rains too much of course the flowers will be flooded and washed away.)

Fallacies_of_Irrelevance.pdf

Some fallacies come from people purposely introducing irrelevant and misleading ideas into an argument in order to distract the dialogue away from the main issue. At times irrelevance is introduced as an attempt to prove something without truly demonstrating evidence that supports the conclusion. We must always beware of points in argument that appear to be deceptive or do not truly contribute to proving the conclusion. Sometimes lawyers introduce irrelevant points to confuse jurors. However, in some cases, people simply do not realize that the points they put forth do not actually contribute to supporting the conclusion they have drawn.

The following are the most common fallacies of irrelevance:

1. Ad baculum (also called Appeal to force)

An appeal to force tries to convince you to accept a conclusion via a threat of force, potential personal damage, or other form of coercion. A common form of ad baculum has to do with an appeal to fear. This fallacy is effective because it is appealing to emotion (Pathos) and is more likely to evoke a response quickly. However, a critical assessment would reveal that there is no evidence offered to support the conclusion. Example: You should believe in God, because if you do not, you will go to Hell.

Whether or not you will go to hell is not relevant evidence that you should believe in God. If you truly do not believe there is a God, then you also do not believe there is a hell, and the fear to which this argument appeals does not exist. However, if directed at those that have doubt, it offers an appeal to fear rather than reasonable, relevant and sufficient evidence to support the need to believe in God. It depends on emotional response for acceptance.

2. Ad hominem

Ad hominem is another name for personal attacks. Three types of personal attacks are commonly used in argument: Circumstantial personal attacks—occur when the opposition tries to undermine another’s argument or claim that their conclusion is invalid by implying that the person making the argument does not "practice what he/she preaches." Example: An argument is put forth that hunting is cruel and wrong and it is better to not eat meat. A hunter responds by attacking the person who is making the argument with an accusation that they eat meat. The implication in the hunter's refutation is that the person making the argument does not do what they are saying should be done and therefore, cannot truly believe their own conclusion. This is a Tu quoque argument - ‘you too!’ or ‘you do it too!’ type of response. Basically, you accuse the other of being a hypocrite. Even though that may be the case, it is irrelevant as to whether eating meat is a good thing. By diverting the discussion to the arguer rather than the issue, the hunter has used irrelevancy to suggest the conclusion is wrong. Abusive ad hominem attacks occur when the opponent attacks the person making the argument by attacking their character and integrity.

Example: Bill Clinton argues that a strong family is important for a child, but everyone knows he is an adulterer! Even though all parts of this statement may be true, the fact that Clinton is an adulterer does not dismiss the possibility that a strong family is important for a child. This claim is about the man, Clinton, and totally irrelevant to the issue at hand – the importance of strong families. Poisoning the well occurs when the opponent attacks the person making the argument by accusing them of having bias, a hidden agenda, or a personal interest in the issue at hand. Example: Jimmy Carter’s views on Arab-Israeli issues must be false since he is angry at Jewish- Americans for not voting for him in 1980 and has accepted money from Saudi Arabia. Example: President Bush's arguments to go to war in Iraq to promote democracy are unfounded because he is a former oil executive interested in causing the price of oil to rise. Example: You can't believe Mr. X‘s statistical research claim that smoking is harmful as he works for companies that make nicotine patches? In each of these instances there is an implication of ulterior motives that is meant to “poison the well,” or prevent you from further listening to this person's argument. However, in no instance has any real reasoning been applied to support the opposite position.

3. Fallacy of opposition

The fallacy of opposition is similar to poisoning the well. It is a specific kind of ad hominem that cuts off all further reasoned dialogue. The attack on the person involves the idea that there is something about the person’s very nature that dismisses anything they have to say as evidence.

Example: John Smith argues that death by lethal injection is not painful, but he has never undergone it.

Although, John Smith might not be able to cite personal experience, it is fallacious to assume that he has not researched his facts or is unable to ascertain the amount of pain involved in the procedure. And the opponent to the position has offered an irrelevant fact, but no evidence that it is painful.

4. Genetic fallacy

The genetic fallacy concludes that the origin of something determines how we must think about it.

Example: Anti-smoking campaigns cannot be positive since the Nazis were the first ones to begin them.

Just because there is a negative connotation with Nazi, does not mean that every practice they began is, in itself, negative. The argument only introduces an irrelevant reference to the geneses of anti-smoking campaign and offers no real evidence that they are not positive.

5. Guilt by association

Similar to the above example that tries to condemn anti-smoking campaigns by associating them with the Nazi's, guilt by association is aimed at persons. This fallacy claims that because something is associated with someone that is liked or despised, the thing itself should also be liked or despised.

Example: I am going to vote for Senator Johnson for president since he was endorsed by another senator who I think would make a good president.

Just because Senator Johnson is associated with the other senator does not mean that he has any of the same qualities. The argument has introduced an irrelevant association and does not offer any real evidence as to why the person is going to vote for Senator Johnson.

6. Ad misericordiam

This is also known as appeal to pity. Similar to ad baculum, ad misericordiam appeals to emotion to persuade you to accept the conclusion rather than offer real evidence that supports the conclusion. Example: I should not be punished for stealing because I was very depressed at the time and stealing is the only thing that makes me feel better. This argument attempts to employ your pity to get you to accept the conclusion that the stealing was ok. However, your possible empathy for a struggle with depression is irrelevant to whether you should consider stealing as acceptable behavior.

7. Ad populum

Ad populum argument claims that if everyone accepts that X is true, then X is actually true. Or: nobody accepts that X is true, therefore X must be false. Example: Mr X's book has been on the best seller list for 10 years. It must be a good book. There is no evidence offered to support the conclusion that the book is good. Rather, the argument introduces irrelevant evidence based on popular belief as demonstrated by the number of people that have bought the book.

8. Bandwagon

Similar to ad populum, the bandwagon fallacy refers to what people do rather than what they believe. It appeals to our willingness to jump on the “bandwagon” as it goes by.

Example: Since no one pays all their taxes in Italy, it must be okay not to do so.

Again, no evidence is presented to support the conclusion that it is okay not to pay taxes. Rather, an irrelevant reference to what others do is the only evidence offered. This is the fallacy parents try to point out when they ask their children "So, if everyone jumped off of a cliff are you going to do it too?"

9. Plain folks and snob appeal

Just as the band wagon appeals to your desire to belong in the group of "everyone", the plain folks and snob appeal fallacy plays on your identification with a certain type of people. The conclusion is supported by irrelevant evidence as to how something or some idea is accepted by the whole group.

Example: Of course Levi's jeans from the Macy's are better than those from Sears. I wouldn’t want anyone knowing I wear jeans from Sears.

The implication is that superior people shop at the Macy's and therefore, you cannot wear Levi's jeans that were purchased at Sears. However, no real evidence has been presented that there is any actual difference in the Levi's jeans regardless of where they are purchased.

Example: The workers of America who value their job cannot support NAFTA (North American Free Trade Act).

The implication is that the plain folk cannot care about international relations or federal GNP, but should only be concerned with keeping their own job. Whether or not a worker values their job is irrelevant as to whether they can understand and support a trade agreement that might benefit the national economy.

10. Ad verecundiam

Ad verecundiam is an unreasonable appeal to a cognitive authority or expertise in order to prove a point. This fallacy is also known as appeal to authority. There are three common appeals to authority: Irrelevant expertise - The argument appeals to an authority on an issue outside the field of expertise that the expert holds. Example: Drinking coffee is clearly bad for you. I just read where Stephen Hawking says we should stop drinking it. As Stephen Hawking is not a qualified health expert, his encouragement to stop drinking coffee is irrelevant to whether coffee is bad for you. Vague Authority - The appeal to authority is too vague to verify or confirm credibility. Example: I know I am going to live a very long time because experts argue that the human lifespan will increase vastly in the next 30 years. This claim leaves you guessing at who the experts are, what they are experts in and what the context of the argument was that is being cited as authority. Without the ability to verify the credibility of the authority, appeals to authority become irrelevant to the argument. This is one reason that when you write you should always properly introduce and cite all source materials. Otherwise, the information you are presenting may appear as a vague appeal to authority and render your overall argument as fallacious. Name-brand Authority – Name recognition may get our attention, but it is not a valid appeal to authority if the person is not really an expert

Example: Of course this teeth whitener works. Julia Roberts says she owes her career to it. We may really be impressed with Julia Robert's smile, but that does not make her an expert on teeth whitener.

11. Red herring

The fallacy of red herring occurs when someone brings up an irrelevant topic in order to deliberately divert attention from the issue at hand. Example: In disputing whether SUVs are environmentally safe one argues: ‘I am not aware of how many miles per gallon they have, but you have to remember that SUVs protect lives of drivers and provide jobs for many in their manufacturing’ If the issue is how environmentally safe SUVs are, then nothing this person has said addresses that issue. Rather it introduces other issues about an SUV to which the conversation might be diverted. Example: If the victim is white and accused is black then racial discrimination will affect the outcome of the trial. Some people believe that OJ Simpson’s defense team, during his trial for murder of his ex-wife, introduced a red herring when they diverted the jury from consideration of the evidence by making it appear as though discrimination against African-Americans and thus Simpson was the issue. We may never know for sure if that jury followed the red herring and allowed the racial issue (that was irrelevant to the guilt or innocence of the accused) to nullify the case rather than examine the evidence of the crime to its fullest.

12. Weak opponent

One example of this is the straw man fallacy that occurs when an argument is distorted or exaggerated to make it appear weaker. In other words, the argument is presented as a straw/empty/weak version, so it is easily disputed and refuted. A straw man fallacy often presents the argument in such a way as to make the conclusion seem impossible to prove, implausible or ridiculous. Example: The workers are demanding a 10 cent raise. I don't understand why they want to put us out of business. In this example, the workers are demanding a raise and the management is expressing that request as a demand to shut down the factory. It is much easier to get others to disregard such an unreasonable request than it would be to justify not considering the raise. Such a straw man can also occur when one uses a loaded term to describe a key term in an argument. For instance, if one describes a position as Nazi-like, one is usually exaggerating to make it appear as an absolute evil.

identifying_arguments_in_visual_media.pdf

Identifying Arguments in Visual Media Many people love going to the movies. Films, movies, provide images that thrill us, frighten us, or that can even make us cry. But films also present arguments or try to persuade us to adopt certain beliefs. Visual arguments in film can be made via camera angles, editing, settings, etc. Critical analysis will allow us to interpret what a film is trying to say to us; what particular ideas it is trying to persuade us to adopt. Since most films have a plot, cinematography, characters, themes, settings, etc; looking more closely at these elements will help in a critical analysis. The first element of a film that is worth exploring is the plot. If we can determine what happened and what did not happen, then we may discover how the plot steers us to think something in particular. By examining whether specific things were highlighted by the camera angles used, allows an additional glance of what is considered important for us to see. The setting used can often reveal a filmmakers attitude to things. Example: The film The Life of David Gale portrays a professor who wants to make the death penalty illegal. The professor is convicted of murdering a colleague. However, it turns out that the professor did not kill the colleague: a video of the colleague committing suicide and the professor filming the suicide is shown at the end of the film. Despite the professor’s innocence, he is executed and goes to death to prove his point that the death penalty can be applied to the innocent. The general consensus is that this film argues against the death penalty. It offers evidence within the plot that innocent people can be convicted of crimes and sentenced to death. But, in the editing even more is revealed. Images change quickly back and for the between the professor’s execution and the video revealing the truth of the matter. They seem to offer an argument by comparison that emphasizes the professor’s innocence and perhaps the wastefulness of both deaths. This could be seen as an appeal to pathos or ethos in an attempt to provoke emotional outrage in the viewer at the injustice of the death penalty.

introduction_to_visual_arguments.pdf

Introduction to Visual Arguments

Arguments are not only composed with words in speeches, dialogues, and written works. Many people try to convince us of things via visual imagery. Advertisement on television, on billboards, images in art galleries, screen layouts on the internet, and other forms of graphic imagery can be used to cause us to think without words and may implicitly lead us to believe certain ideas.

Photographs are found in magazines, newspapers, advertisements, and art galleries. A photographer never simply holds up a mirror to the world. Photographers deliberately publish certain images to communicate specific ideas, thoughts, and feelings. While photographic images may make us think we are simply looking through a window on the world, the look of the picture itself is actually carefully constructed. We only see what the photographer allows us to see.

We need special tools to analyze what a photograph is attempting to get us to think or feel. Analyzing imagery is somewhat different than analyzing written or spoken arguments. True to the old adage, "A picture is worth a thousand words," when we look at images we take in just as much or more information as we do when we read a sentence. The initial task in receiving that information is to try to express in words what we see the picture ‘saying.’ This allows us to become aware of what the specific image is communicating to us. We naturally grasp meaning intuitively. But, we need to consciously articulate that meaning. Not that you need to talk to yourself out loud whenever looking at an image, but you need to engage in a mental process of interpreting visual meaning into words. For instance, some of the things we might articulate would be a description of what we see. Since our critical thinking is attuned to word play, the mere transposition of the mute experience into words allows us to better apply critical thinking skills.

The following steps will help you organize your thoughts when describing a photograph:

1. Search for the central focus of the photograph. The focus will often equate to the goal of the communication and indicate what might be the main theme or message or thesis of the photograph? What does the picture highlight and draw attention to?

2. Next, observe what is going on in the picture. What are the people doing in the photograph? Where was the picture taken? From what angle was the picture shot?

3. Given the purpose you ascribe to the image, ask yourself if the image succeeds in communicating what you claim it does. Does the picture successfully make you feel the emotion you believe it is trying to arouse?

Of course, visual imagery does not consist exclusively of photographs. We are also confronted with paintings in art galleries and on the walls of homes and business. We can use the same techniques to look at paintings.

Most commonly, we encounter imagery used by the advertising industry aimed at persuading consumers to buy products, persuading voters to support a specific candidate or cause, or providing awareness of a special interest issue. Advertisers and marketing teams skilfully choose the best images and slogans to get the attention of the audience and convince them that a product, a cause, or a candidate is worth the commitment of time or money.

If we critically analyze visual advertisements, we can discover the arguments they are communicating. Critical questions to be considered include:

• Who is the intended audience of the advertisement? Is the advertisement directed to people who are sick with heart disease? Is the advertisement directed at children?

• What does the advertisement claim is desirable? Success? Beauty? Health? Speed? Do we agree that what is being claimed as desirable is actually something we desire?

• What is the goal of the advertisement? Is it trying to convince you to buy a hamburger or vote for a particular candidate?

• How does the ad try to persuade you to act or adopt a belief? Does it appeal to fear of what might happen if you don't act or accept the belief? Does is appeal to pity? Does it present reasonable, relevant and sufficient evidence?

• Based on the above answers, should the ad convince a rational person? Does it employ deceptive or misleading approaches that may be effective on non-critical thinkers?

Example: A commercial uses a handsome actor, who plays a doctor on a soap opera, to suggest that a specific medicine should be used to remedy colds. The actor does disclose that he is not a real doctor. He holds up a package of the medicine and lists several benefits such as how the medicine helps you to sleep when you are stuffed up and how good it tastes. And of course, he recommends that you buy it.

The advertisement is clearly aimed at anyone who has or will have a cold. It makes it seem desirable to be able to get sleep and to have good tasting medicine. The purpose seems clear: to convince you to buy and use the medicine the next time you have a cold. The ad tries to convince you by the beauty of the actor (people tend to want to be like the beautiful), the fact that people think of the actor as a doctor (appeal to authority), and by listing the desirable aspects of a medicine (tastes good and helps you sleep). But does the ad succeed? Would a reasonable person buy the medicine based on this ad? Is there a fallacious appeal to authority? Are good taste and being able to rest enough evidence to support such a conclusion to buy this particular medicine? You can also write the argument out in words to better analyze the content. Example: A handsome actor claims this medicine tastes good.

A soap opera doctor says this medicine will help you rest. You should buy and use this particular medicine if you have a cold.

Now, we can analyze the argument found in the advertisement just as we have all other arguments up to this point. Is the evidence offered relevant, reasonable and sufficient to support the conclusion?

primary_and_secondary_evidence.pdf

Primary and Secondary Evidence

Primary evidence is the evidence that you, as the researcher or writer, unearth on your own via surveys, interviews, laboratory work, or other things that can be verified first hand.

Secondary evidence is what may be found by examining the work of others. It relies on the writings, letters, books, articles, etc. of others. When dealing with secondary evidence, you must engage with the ideas and research of others and analyze it in order to explain it, use it as support of your own view, or argue against it.

Both types of evidence are useful. However, as we have been discussing, it is very important to be sure the secondary evidence used comes from a trustworthy and reliable source.

reliable_sources_of_information.pdf

Reliable Sources of Information Many people who design and maintain websites also infuse the information on these sites with their own personal bias and opinions. We all use the Web for research, entertainment, to communicate with friends, and further our education or learn new things. How can we trust the information we find there? Is it reliable? What critical thinking skills can help determine whether or not to trust what is on a website?

If we go to a local library, most texts and periodicals there can be trusted since the community at large has reviewed them and decided they do not contain misleading information. Often, the company publishing a text will have a fact-checker who documents all that is claimed in a text or periodical. Mistakes are often pointed out by readers such that new editions of a work include revisions. On the Web, most of what we might read is unedited and not checked by the community at large for consistency and truth. Here are some reasons why the Web can be untrustworthy

1. It can be updated and changed in an instant. Whereas a book requires a long process of re- publication to undergo change, information on a website can be changed in a few minutes or the entire website can be removed with the push of a button. In such instances, it makes it impossible for anyone to double check the site material being referenced.

2. Most books, newspaper articles, magazine pieces, etc. have known authors who one can contact and who have a reputation for a consistent body of work. However, on the internet, anyone can publish anything under any name, even anonymously. Identifying the real author of the website is often difficult since the name may not help in finding the real person who stands behind the content.

Brand name resources are often the most trustworthy websites. For instance, the Chicago Tribune website for news can be considered a trusted source since it has a long-standing reputation as a credible news source.

The World Wide Web offers a world of information and another whole world of disinformation or unfounded information. You must be careful and use critical thinking skills to select appropriate web sources.