Key to all exercises.doc

September 25, 2017 | Author: Tiên Nguyễn | Category: Inductive Reasoning, Validity, Deductive Reasoning, Argument, Relativism
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Exercise Answers and Teaching Tips Chapter 1: Introduction to Critical Thinking Students enjoy the exercises in Chapter 1. Most are Socratic exercises, designed to ease students into the course and encourage self-reflection in dialogue with others. Instructors probably won't want to do all the exercises in this chapter: We generally do about half. Exercise 1.1.1 works well as an icebreaker. Students always enjoy Exercises 1.2 and 1.3, and Exercises 1.6.I and 1.6.III work well for instructors who stress writing. Exercise 1.1 I. As noted above, this exercise works well as an icebreaker. We use it mainly to highlight the difference between lower-order thinking and higher-order thinking. II. Having grown up on Jerry Springer and Ricki Lake, today's students are surprisingly frank about their practical and intellectual inconsistencies. If discussion does falter, try discussing the hypocrisies of public figures. Exercise 1.2 Students enjoy this simple test, which takes only a few minutes to take and self-grade. Students are amazed by how poorly they do. (Most only get two or three answers correct.) This brings home to them in a way no lecture could their own proneness to intellectual overconfidence. Exercise 1.3 Students have fun with this exercise, and it is very effective in making clear to them how strongly our thinking is influenced by unconscious assumptions and stereotypes. Students invariably assume, for example, that the Captain is a man, that Dr. Brown is a man, that Dr. Brown is a medical doctor, that Dr. Brown and Marie Brown are related as either husband and wife or as father and daughter—despite the fact there is no textual evidence to support any of these assumptions. Allow at least 20-30 minutes for this exercise.


Exercise 1.4. Below are some crib notes we use in our own classes when teaching this exercise. Case 1 Key Facts:    

You are a member of Culture C and a moral relativist. You are studying cultures A and B. A is a pacifist culture; B is a militaristic and slaveholding culture. B invades A.

Discussion questions: 1. What can you consistently believe with regard to Culture A? Answer: You must believe that it is right for Culture A to be a totally pacifist culture, and hence that it is right for Culture A to permit themselves to be conquered and enslaved by Culture B. (Assuming that this belief is consistent with what you must believe as a member of Culture C.) 2. What can you consistently believe with regard to Culture B? Answer: You must believe that it is right for Culture B to be a militaristic and slaveholding culture, and hence that it is right for Culture B to conquer and enslave Culture A. (Assuming that this belief is consistent with what you must believe as a member of Culture C.) 3. What can you consistently do with regard to Culture A? Answer: Since both Culture A and Culture B are doing what they consider to be morally right, you cannot do anything to interfere with the invasion. (Assuming that your noninterference is permitted by the values of Culture C.) 4. What can you consistently do with regard to Culture B? Answer: You cannot do anything to interfere with Culture B’s conquest of Culture A. (Assuming that your noninterference is permitted by the values of Culture C.) Main Lesson of Case 1: Moral relativism may commit us to certain beliefs or practices that, intuitively, seem to us to be terribly wrong. It makes it impossible for us to criticize the values and practices of other cultures that may seem to us to be clearly wrong or misguided.


Case 2 Key Facts:    

You are a member of Culture B and a moral relativist. A is a pacifist culture; B is a militaristic and slaveholding culture. Culture B believes that it is wrong for Culture A to practice pacifism. Culture B invades Culture A, and seeks to enslave them and force many of them to participate in gladiatorial bouts.

Discussion questions: 1. Is there any logical difficulty with being a relativist and also belonging to Culture B? Answer: Yes. As a moral relativist you must believe that it is right for Culture A to practice pacifism (since this is what Culture A believes is right). But as a member of Culture B you must believe that it is wrong for Culture A to practice pacifism (since this is what Culture B believes). 2. What can you consistently believe with regard to Culture A? Answer: As explained above, you are committed to inconsistent beliefs with regard to Culture A. You must believe that it is right for Culture A to practice pacifism and that it is wrong for Culture A to practice pacifism. 3. What can you consistently believe with regard to Culture B? Answer: You must believe that it is right for Culture B to subjugate and enslave Culture A. (Instructors might wish to note that, strictly speaking, inconsistent beliefs imply any conclusion.) 4. What can you consistently do with regard to Culture A? Answer: Since both Culture A and Culture B are doing what they consider to be right, you, as a member of Culture B, must support the invasion—and indeed participate in it if required to do so. 5. What can you consistently do with regard to Culture B? Answer: You must support and possibly participate in the invasion and subjugation.


Main Lessons of Case 2: 1. Moral relativism may commit us to certain beliefs or practices that, intuitively, seem to us to be terribly wrong. 2. Moral relativism can easily lapse into inconsistency. One way this can happen is when a relativist is a member of a society that holds beliefs that conflict with moral relativism (as Culture B does in this scenario). Another way inconsistency can occur is when a relativist belongs to a culture that holds inconsistent moral beliefs. A third way in which relativism can lead to inconsistency is explored in Case 3. Case 3 Key Facts:      

You are a member of Culture B, a moral relativist, and a member of sub-culture Beta. Culture A is a totally pacifist culture. Culture B consists of two sub-cultures: the Alphas, a ruling majority group, and the Betas, an oppressed minority group with its own distinctive beliefs and practices. The Alphas believe that it is morally right to annually sacrifice a young child; the Betas believe strongly that child sacrifice is wrong. The Alphas also believe that it is wrong that Culture A does not practice child sacrifice, and that it is right for them to impose this belief on Culture A. Culture B invades Culture A, and begins its program of indoctrination.

Discussion questions: 1. Is it possible for an individual to belong to more than one culture at the same time? If so, does this impose any logical difficulty for the moral relativist? Answer: Arguably, yes. The Amish, for example, plausibly belong to two cultures: the larger American culture and their own distinctive sub-culture. If an individual belongs to different cultures, and the cultures hold mutually inconsistent moral beliefs, then moral relativism implies inconsistent moral duties. 2. Is there any logical difficulty in being a relativist and belonging to Culture B? Answer: Yes, for the same reason stated in Case 2. You must believe both that Culture A is right not to practice child sacrifice and that Culture A is wrong not to practice child sacrifice.


3. What can you consistently believe with regard to Culture A and Culture B? Answer: You seem to be committed to holding inconsistent beliefs: that child sacrifice is both right and wrong for Culture B, and that child sacrifice is both right and wrong for Culture A. 4. What can you consistently do with regard to Culture A and Culture B? Answer: You would have inconsistent duties--for example, both to support and not to support child sacrifice. 5. If someday the Betas become the majority sub-culture in Culture B, and consequently most members of Culture B no longer believe in child sacrifice, can this be described as "moral progress" from the standpoint of moral relativism? Answer: No. According to moral relativism, what is morally right for a society is whatever that society believes is right at a particular time. Thus, according to relativism, it is not the case, for example, that contemporary Americans' attitudes toward slavery are "truer" or "more enlightened" than those of most 18th century Americans. Both views are equally true for the people at those times. Exercise 1.5 Students may be confused at first about how some of these critical thinking hindrances differ from one another. Encourage them to begin with definitions of the hindrances and then to work systematically through them, providing examples of each. Exercise 1.6 I. Students enjoy this exercise in self-examination, and it provides a good opportunity early in the course for instructors to offer rapport-building feedback. II. The following definitions are offered on the Center for Critical Thinking Web site ( 

Intellectual humility: Having a consciousness of the limits of one's knowledge, including a sensitivity to circumstances in which one's native egocentrism is likely to function self-deceptively; sensitivity to bias, prejudice and limitations.


Intellectual courage: Having a consciousness of the need to face and fairly address ideas, beliefs or viewpoints toward which we have strong negative emotions and to which we have not given a serious hearing.

Fair-mindedness: Having a consciousness of the need to treat all viewpoints alike, without reference to one's own feelings or vested interests, or the feelings or vested interests of one's friends, community or nation.

Intellectual perseverance: Having a consciousness of the need to use intellectual insights and truths in spite of difficulties, obstacles, and frustrations; firm adherence to rational principles despite the irrational opposition of others; a sense of the need to struggle with confusion and unsettled questions over an extended period of time to achieve deeper understanding or insight.

The Web site also offers definitions of three additional intellectual traits: intellectual empathy, intellectual integrity, and faith in reason. Here are two dictionary definitions of open-mindedness: "Having or showing receptiveness to new and different ideas or the opinions of others." (Source: The American Heritage Dictionary of the English Language, 3rd ed.) "Willingness to listen to other people and consider new ideas, suggestions and opinions." (Source: Cambridge International Dictionary of English.) III. Unfortunately, many students know very little about such intellectually courageous figures as Socrates, Luther, St. Thomas More, Spinoza, or Susan B. Anthony. If time permits, you might ask students to read Plato's Apology and perhaps the Crito or Phaedo as well. This will take a few class periods but the critical-thinking lessons they teach are important.

Chapter 2: Recognizing Arguments Exercise 2.1 I. 1. 2. 3. 4. 5.

Statement Nonstatement (question) Statement Nonstatement (suggestion) Statement


6. Nonstatement (suggestion or exhortation) 7. Statement (This is a brief and emphatic way of saying, "This is great.") 8. Nonstatement (command) 9. Nonstatement (order or request) 10. Statement (You might be lying.) 11. Statement (rhetorical question) 12. Nonstatement (exclamation) 13. Nonstatement (request) 14. Statement (rhetorical question) 15. Nonstatement (question) 16. Statement (This is an emphatic way of saying, "This is a crock.") 17. Nonstatement (This could be an ought imperative in some contexts, but more likely it is a request, suggestion, or order.) 18. Statement 19. Nonstatement ("Please" indicates that this is a request) 20. Nonstatement (petition) 21. Nonstatement (suggestion or proposal) 22. Statement (Spanish for "My house is your house.") 23. Statement (rhetorical question) 24. Statement (rhetorical question) 25. Nonstatement (exclamation) II. 1. Yes 2. No (command) 3. Yes 4. Yes 5. No (suggestion) 6. No 7. Yes 8. Yes 9. Yes 10. Yes 11. No 12. Yes 13. Yes 14. No 15. Yes Exercise 2.2 I. 1.

Premise: Light takes time to reach our eyes.


Conclusion: All that we see really existed in the past. 2.

Premise 1: Life changes when you least expect it to. Premise 2: The future is uncertain. Conclusion: Seize this day, seize this moment, and make the most of it.


Premise: A good name shall continue with thee, more than a thousand treasures precious and great. Conclusion: Take care of a good name.


Premise: Faith means believing a proposition when there is no good reason for believing it. Conclusion: Faith is a vice.


Premise: If you are not very careful about lying, you are nearly sure to get caught. Conclusion: You want to be very careful about lying.


Premise: There is no definitive way to prove any one set of religious beliefs to the exclusion of all others. Conclusion: Religious freedom is a human right.


Premise: Science is based on experiment, on a willingness to challenge old dogma, on an openness to see the universe as it really is. Conclusion: Science sometimes requires courage--at the very least the courage to question the conventional wisdom.


Premise 1: You may not be able to hear warning sirens from emergency vehicles. Premise 2: Hearing damage from loud noise is almost undetectable until it's too late. Conclusion: Do not play your sound system loudly.


Premise 1: Without symbols, no intellectual advance is possible. Premise 2: With symbols, there is no limit set to intellectual development except inherent stupidity. Conclusion: The invention or discovery of symbols is doubtless by far the single greatest event in the history of man.


Premise: On average, the lowest animal is a lot nicer and kinder than most of the human beings that inhabit the earth. Conclusion: Animals have souls.


Premise: The more stupid a member of Parliament is, the more stupid his constituents were to elect him. Conclusion: Democracy has at least one merit, namely, that a member of Parliament cannot be stupider than his constituents.



Premise: When senility hit you, you won't know it. Conclusion: Don't worry about senility.


Premise: Oil isn't helping anyone when it sits in the ground. Conclusion: There's nothing wrong with burning crude [oil] like crazy, so long as there's a plan for energy alternatives when the cheap oil runs out.


Premise: Everyone recalls the famous incident at Sybil Seretsky's when her goldfish sang "I Got Rhythm"--a favorite tune of her deceased nephew. Conclusion: There is no doubt that certain events recorded at seances are genuine. 15.

Premise: We need quality highways to handle the sharp increase in the number of Mercedes automobiles purchased by lawyers enriched by the tobacco settlement. Conclusion: It's good that so far states are spending more than 90 percent of the tobacco settlement money on programs unrelated to smoking, such as building highways. 16.

Premise: If we encourage each other to blame God for injustice, we are giving the evil or dark side a victory by keeping God's precious children–that's all of us–away from His loving arms. Conclusion: Although it's part of human nature to be angry at God when bad things happen, there' s no point in doing so.


Premise 1: In great contests each party claims to act in accordance with the will of God. Premise 2: God cannot be for and against the same thing at the same time. Conclusion: Both parties in great contests may be, and one must be, wrong.


Premise 1: The Alaska bears are a distinct species. Premise 2: Relegating grizzlies to Alaska is like relegating happiness to heaven-one may never get to heaven or Alaska. Conclusion: It is not good enough for me if grizzlies survive only in Canada and Alaska.


Premise 1: More than 99 percent of the creatures that have ever lived have died without progeny. Premise 2: Not a single one of your ancestors falls into this group. Conclusion: You are very lucky to be alive.


Premise: You put a pen in there, you roll over in the middle of the night, you kill yourself. Conclusion: You don't need a breast pocket on your pajamas.


II. 1.

Premise 1: Man knows that he is dying. Premise 2: Of its victory the universe knows nothing. Conclusion: When the universe has crushed him man will still be nobler than that which kills him.


Premise 1: Rights are either God-given or evolve out of the democratic process. Premise 2: Most rights are based on the ability of people to agree on a social contract, the ability to make and keep agreements. Premise 3: Animals cannot possibly reach such an agreement with other creatures. Premise 4: Animals cannot respect anyone else's rights. Conclusion: Animals cannot be said to have rights.


Premise 1: I need a man. Premise 2: My heart is set on you. Conclusion: You’d better shape up.


Premise 1: Moral responsibility presupposes free-will. Premise 2: This freedom is not compatible with universal causal determinism. Premise 3: Universal causal determinism appears to be the case. Conclusion: Contrary to what most people believe, human beings are not morally responsible.


Premise 1: Our faith comes in moments. Premise 2: Our vice is habitual. Premise 3: There is a depth in those brief moments which constrains us to ascribe more reality to them than to all other experiences. Conclusion: The argument which is always forthcoming to silence those who conceive extraordinary hopes of man, namely the appeal to experience, is forever invalid and vain. 6.

Premise 1: Travel articles appear in publications that sell large, expensive advertisements to tourism-related industries. Premise 2: These industries do not wish to see articles with headlines like "Uruguay: Don't Bother." Premise 3: (subconclusion): No matter what kind of leech-infested, plumbing free destination travel writers are writing about, they always stress the positive. Conclusion: Never trust anything you read in travel articles.


Premise 1: If you are not speeding, you don't have to worry about speed traps. Premise 2: Speed traps could save your life if some other speeder is caught. Conclusion: No one in his right mind can criticize the state police for speed traps.




Premise 1: Philosophy is dangerous whenever it is taken seriously. Premise 2: So is life. Premise 3: Safety is not an option. Conclusion: Our choices are not between risk and security, but between a life lived consciously, fully, humanly in the most complete sense and a that just happens.


Premise: Our nation protests, encourages, and even intervenes in the affairs of other nations on the basis of its relations to corporations. Conclusion: We cannot dissociate ourselves from the plight of people in those countries.


Premise: He that loveth not his brother whom he hath seen, cannot love God whom he hath not seen. Conclusion: If a man say, "I love God" and hateth his brother, he is a liar.


Premise 1: Each of us has an intellectual dimension to his existence. Premise 2: We need ideas as much as we need food, air, or water. Premise 3: Ideas nourish the mind as the latter provide for the body. Conclusion: We need good ideas as much as we need good food, good air, and good water.


Premise 1: The only criterion for distinguishing right from wrong is the moral system of the society in which the act occurs. Premise 2 (subconclusion): The only ethical standard for judging an action is the moral system of the society in which the act occurs. Conclusion: What is right in one place may be wrong in another.


Premise: If you don't accept reality the way it occurs--namely, as highly imperfect and filled with most fallible human beings—you will experience continual anxiety and desperate disappointments. Conclusion: Whether you like it or not, you'd better accept reality the way it occurs: as highly imperfect and filled with most fallible human

beings. 14.

Premise 1: The more vivid our sense of the approach of death, the more we relish the small things in life. Premise 2 (subconclusion): Death is necessary for our appreciation of life. Premise 3: Death is necessary for the continued march of evolutionary improvement, an ongoing process leading to more valuable states of good, to take place on earth. Conclusion: We should be emotionally reconciled to the fact of death, rather than fearing it.



Premise: The hit rock songs of 1974 included "Kung Fu Fighting," "Seasons in the Sun," "Billy Don't Be a Hero," "The Night Chicago Died" and "(You're) Having My Baby." Conclusion: It is a scientific fact that 1974 was the worst year in world history for rock music.


Premise 1: Those who develop the first-thing-in-the-morning routine tend to be more consistent in their training. Premise 2: Morning runs avoid the heat and peak air pollution. Premise 3: You can enjoy your runs without carrying along all the stress that builds up during the day. Premise 4: Early-morning runs save time by combining your morning and postrun shower. Conclusion: Getting in your run early certainly has its advantages.


Premise 1: You go to Duke and it has everything you dream about in college basketball. Premise 2: Guys play hard. Premise 3: They go to class. Premise 4: They do things the right way. Premise 5: They have discipline. Premise 6: They go out and win. Premise 7: The crowd is behind them. Conclusion: There is nothing not to like about Duke University men’s basketball program.


Premise 1: College professors don’t know how to live any better than the rest of us. Conclusion: The art of how to live can’t be taught in college.


Premise 1: You’ll begin to eat food in season, when they are at the peak of their nutritional value and flavor. Premise 2: You won’t find anything processed or microwavable. Premise 3 (subconclusion): You’ll cook. Premise 4: You’ll be supporting the farmers in your community. Premise 5: You’ll be helping defend the countryside from sprawl. Premise 6: You’ll be saving oil by eating food produced nearby. Premise 7: You’ll be teaching your children that a carrot is a root, not a machinelathed orange bullet that comes in a plastic bag. Conclusion; Shop at the farmer’s market.


Premise 1: When you understand other positions and points of view, you often learn something new and expand your horizons. Premise 2: When the person you are talking to feels listened to, he or she will appreciate and respect you far more than when you habitually jump in with your own position.


Premise 3: A side benefit is that the person you are speaking to may even listen to your point of view. Conclusion: The next time you find yourself in an argument, rather than defend your position, see if you can see the other point of view first. Exercise 2.3 Students with less developed literacy skills often find it very difficult to distinguish arguments from explanations. This exercise allows students to reflect on a large number of generally straightforward examples in a format that encourages active learning. It is also a good source of student-generated examples for quizzes and exams. Exercise 2.4 I. 1. Nonargument (explanation) 2. Argument 3. Nonargument (explanation) 4. Nonargument (conditional statement) 5. Nonargument (explanation) 6. Argument 7. Nonargument (report of an argument) 8. Nonargument (illustration) 9. Nonargument (explanation) 10. Nonargument (illustration) 11. Argument 12. Nonargument (conditional statement) 13. Nonargument (report of argument). (The writer is reporting, not endorsing, Gladstone's argument.) 14. Nonargument (explanation) 15. Nonargument (unsupported assertion) 16. Nonargument (report of an explanation) 17. Nonargument (unsupported assertion) 18. Argument 19. Nonargument (unsupported assertion). (Notice that the word "because" does not function as a premise indicator in either sentence of this passage.) 20. Nonargument (unsupported assertion) 21. Nonargument (explanation) 22. Nonargument (unsupported assertion) 23. Nonargument (unsupported assertion) 24. Argument 25. Nonargument (illustration) 26. Argument


27. Nonargument (unsupported assertion) 28. Nonargument (conditional statement) 29. Nonargument (explanation) 30. Nonargument (unsupported assertion) II. 1. Explanation 2. Argument 3. Explanation 4. Argument 5. Explanation 6. Explanation 7. Explanation 8. Explanation 9. Explanation 10. Explanation 11. Argument 12. Explanation 13. Explanation 14. Explanation 15. Argument 16. Explanation 17. Argument 18. Explanation 19. Explanation 20. Explanation

Chapter 3: Basic Logical Concepts Exercise 3.1 I. 1. Moriarty 2. Adler, with the revolver 3. Windibank, with the rope, on the downs


II. 1.

Mike: Grape juice Amy: Pepsi Brian: Diet Coke Lisa: Iced tea Bill: 7-Up

2. China and Japan are out because Seth does not want to go to Asia. Australia is out because Maria does not want to go to any country south of the equator. Canada is out because Antoine wants to study in Europe or Australia. England is out because JoBeth is willing to go anywhere except England. Therefore, by a process of elimination, the answer is Germany. 3. Buck: Soda Jennifer: Pretzels Li: Dip Ursula: Chips Tyler: Ice cream Exercise 3.2 1. Modus tollens 2. Affirming the consequent 3. Modus ponens 4. Chain argument 5. Denying the antecedent 6. Modus ponens 7. Denying the antecedent 8. Affirming the consequent 9. Chain argument 10. Affirming the consequent Exercise 3.3 1. Deductive (Argument based on mathematics; also, the conclusion follows necessarily from the premises.)


2. Inductive (Argument from authority; also, the conclusion follows only probably from the premises; also, "it’s reasonable to believe that” is an induction indicator phrase.) 3. Inductive (Statistical argument; also, the conclusion follows only probably from the premises; also, probably is an induction indicator word.) 4. Deductive (Argument by elimination; also, the conclusion follows necessarily from the premises.) 5. Deductive. (The conclusion follows necessarily from the premises; also, obviously is a deduction indicator word.) 6. Inductive (Causal argument; also, the conclusion does not follow necessarily from the premises.) 7. Inductive (Given that signs can be wrong, the conclusion follows only probably from the premises.) 8. Deductive (Argument by definition; also, the conclusion follows necessarily from the premises.) 9. Deductive (Categorical syllogism; also, the conclusion follows necessarily from the premises.) 10. Inductive (Argument from authority; also, a prediction; also, probably is an induction indicator word; also, the conclusion does not follow necessarily from the premises.) 11. Deductive (Hypothetical syllogism; note, however, that the conclusion does not follow necessarily from the premises.) 12. Deductive (The conclusion follows necessarily from the premises.) 13. Inductive (The principle of charity dictates that the argument be regarded as inductive, because the conclusion follows at best probably from the premises.) 14. Inductive (Causal argument; also, the conclusion does not follow necessarily from the premises.) 15. Inductive (Inductive generalization; also, probably is an induction indicator word; also, the conclusion does not follow necessarily from the premises.) 16. Inductive (Argument from authority; also, the conclusion does not follow necessarily from the premises.)


17. Deductive (Hypothetical syllogism; note, however, that the conclusion does not follow necessarily from the premises.) 18. Inductive (Argument from analogy; also, the conclusion does not follow necessarily from the premises.) 19. Inductive. (The principle of charity dictates that the argument be regarded as inductive, because the conclusion does not follow necessarily from the premises.) 20. Deductive (Argument by definition; also, the conclusion follows necessarily from the premises; also, “it must be the case that” is a deduction indicator phrase.) 21. Deductive. (The conclusion follows necessarily from the premises.) 22. Deductive (Argument by elimination; also, the conclusion follows necessarily from the premises.) 23. Inductive (Argument from authority; also, the conclusion follows only probably from the premises.) 24. Inductive (Predictive argument; also, the conclusion follows only probably from the premises.) 25. Deductive (Argument based on mathematics; also, conclusion follows necessarily from the premises; also, "it necessarily follows" is a deduction indicator phrase.) Exercise 3.4 1. Beta. 2. Alpha. 3. Delta is a beta. 4. Delta is not an alpha. 5. Delta is not a beta. 6. Delta is not an alpha. 7. If Delta is an alpha, then Delta is a theta. 8. Delta is a beta. 9. Either Delta is a theta or Delta is a sigma. 10. Some alphas are thetas (or: Some thetas are alphas). Exercise 3.5 I. 1. Valid


2. Valid 3. Invalid (affirming the consequent) 4. Invalid (denying the antecedent) 5. Invalid 6. Invalid (Not all lions have four legs.) 7. Valid 8. Valid 9. Invalid 10. Invalid II. 1. Sound 2. Unsound (The first premise is false.) 3. Sound 4. Unsound (invalid argument: affirming the consequent) 5. Sound 6. Sound 7. Unsound (invalid argument: denying the antecedent) 8. Unsound (The argument is invalid.) 9. Unsound (The argument is invalid.) 10. Unsound (false premise) III. 1. Cogent 2. Uncogent (Although cigarette smoking significantly increases one's risk of dying from lung cancer, most heavy smokers do not die from lung cancer.) 3. Uncogent (false premise) 4. Uncogent (The analogy is a bad one, and the second premise is false.) 5. Cogent 6. Uncogent (The conclusion does not follow probably from the premises.) 7. Cogent 8. Uncogent (The first premise is false.) 9. Cogent. 10. Uncogent (The conclusion does not follow probably from the premises.) IV. 1. 2. 3. 4.

Deductive, valid Deductive, valid Inductive, strong Inductive, weak


5. Inductive, strong 6. Deductive, invalid (three socks would suffice) 7. Inductive, strong 8. Deductive, invalid 9. Deductive, valid 10. Inductive, weak 11. Inductive, strong 12. Inductive, strong 13. Inductive, weak 14. Deductive, valid 15. Deductive, invalid 16. Inductive, weak 17. Deductive, invalid 18. Inductive, weak 19. Inductive, strong 20. Deductive, invalid


Chapter 4: Language Exercise 4.1 I. 1. Vague and overgeneral. 2. Overgeneral. 3. Overgeneral. 4. Overgeneral. 5. Vague and overgeneral. 6. Vague and overgeneral. 7. Overgeneral. 8. Vague and overgeneral. 9. Overgeneral. 10. Vague and overgeneral. II. It’s important in this exercise that students are able to tell how they might clear up the confusion in ambiguous sentences. In some cases, however (numbers 2 and 16, for example), the ambiguity is intended. In the case of vagueness, students should be able to say which sentences make deliberate and necessary use of vague language. 1. Vague and overgeneral (not to mention ungrammatical). Terms such as “verbal assaults” and “derogatory comments” are highly vague. Much of the language is also overgeneral (e.g., any language or behavior that “challenges” another person or puts them “in a state of fear or anxiety” apparently counts as harassment). 2. Ambiguous because of unclear pronoun references. “It” could refer to Sheridan’s having called the honorable member a liar or to the honorable member’s being a liar. 3. Ambiguous. Should the security officer have experience as a shoplifter or as someone who has enforced laws against shoplifting? 4. Unhelpfully vague. How likely is it to rain? 5 percent? 95 percent? 5. Ambiguous. Who, precisely, is on drugs? 6.

Ambiguous. “With relish” could refer to the condiment made of chopped pickles, or it could describe the enjoyment with which the cheesecake was eaten.


7. Ambiguous. Whose bottom is enormous, Ellen’s or the ship’s? (If you have time, you might use this comical sentence to remind students about the confusion caused by dangling modifiers.) 8. Overgeneral. Of course the minister “was against” sin, but Coolidge, very cleverly, doesn’t provide specifics. 9. Ambiguous. Does this mean (a) that only riders carrying dogs may ride the elevator or (b) that riders accompanied by dogs must carry those dogs? 10. Ambiguous. Who is hot, Bob or Devlin? And "hot " in what sense? 11. Ambiguous. 12. Ambiguous. Without parentheses it is impossible to know how to proceed in solving this equation. Is it (3 + 5) x 3 = 24? Or is it 3 + (5 x 3) = 18? 13. Ambiguous. 14. Ambiguous. The verb bear can mean carry, produce, or tolerate. 15. Ambiguous. 16. Brilliantly ambiguous. The phrase “lose no time in reading it” can be read to mean that Disraeli would immediately read the manuscript or refuse to waste his time. 17. Vague and overgeneral. The words small and brown have fuzzy meanings (How small? What shade of brown?). And the phrase “small brown dog” is not specific enough to distinguish the lost dog from many other dogs. “Generous reward” is also vague because there are many borderline cases. A million dollars is clearly generous; a nickel is not. But what about one hundred dollars? 18. Ambiguous. A teacher is hitting lazy students, or the teachers are on strike, which is leaving the kids with nothing to do. 19. Ambiguous pronoun reference: she can refer to either Jana or her sister. 20. Ambiguous, thankfully.


III. 1. Verbal 2. Factual 3. Verbal 4. Factual 5. Verbal 6. Verbal 7. Factual 8. Verbal Exercise 4.2 I. Answers to the exercise will vary greatly. The point of the exercise is to show students that they should attempt to define terms to the satisfaction of their readers and listeners; therefore, they should avoid personal or persuasive definitions and focus on lexical and precising ones. The exercise also helps students recognize the value of illustrations in defining terms, given that terms like rock and roll and horror movie can hardly be defined well without examples. Many of the words in the list lend themselves well to genus and difference definitions, because students must supply characteristics to distinguish, for example, one type of music from another. II. This exercise works well for class discussion and as a source of assignments for short papers. When assigning papers based on this exercise, I ask students to choose one item and to organize their papers into two main sections, the first defining the term and the second applying the definition to the action to show whether the action fits the definition. Class discussions, however, are not as formal or premeditated, and some very interesting conversations ensue when students give their initial responses to the question and find themselves trapped in inconsistencies. Two words of caution: some definitions (assault, for example) require legal definitions that must be located in specialized sources such as Black’s Law Dictionary. And some of the items can—and probably should—be limited to a particular context. In class discussion you can provide contextual parameters to help narrow the question. Below are two short essays I received from students. For some readers the second essay may present too simplistic a definition of “art,” but the writer shows that he can use various strategies to define a term. 5. Nancy has a paper due tomorrow morning. She has written a very rough, undeveloped draft. Last semester Nancy’s roommate, Sharon, wrote a paper on the very same topic. Sharon gives Nancy the paper and tells her to “take as much of it as you want.” With


Sharon’s permission and help, Nancy uses Sharon’s paper to develop her own. Is Nancy guilty of “plagiarizing”? The question is whether Nancy is guilty of plagiarizing her roommate Sharon's paper for a Critical Thinking class. I believe that Nancy is guilty of plagiarism because she did not complete the paper using her own knowledge and ability. The definition of plagiarism is very clear. According to Merriam-Webster's Collegiate Dictionary, plagiarism means, "to steal and pass off (the ideas or words of another) as one's own; use (a created production) without crediting the source" (“Plagiarism”). It is deliberately and voluntarily copying another person's work word-forword. The person is just restating what someone else has said. A new or original idea is not being presented, and he or she knows that what they are doing is wrong, yet they choose to do so anyway. The definition in no way excuses copying another person's work even if the other person gives permission. "To put your name on a piece of work any part of which is not yours is plagiarism, unless that piece is clearly marked and the work from which you have borrowed is fully identified.". Plagiarism is “a form of theft" (“Plagiarism,” Academic). The term plagiarism directly applies to the situation of Nancy and her roommate Sharon. Nancy has waited until the last minute to write a paper for her class. She has been lazy in not doing her work, but now she realizes that she has run out of time. Her roommate, thinking that she is being a good friend by helping Nancy out, tells her to "take as much of it as you want", referring to the paper she wrote last semester on the same topic. Despite the fact that Sharon willingly gave the paper to Nancy, when the definitions given above are taken into account, she has still committed an act of plagiarism. Nancy has deliberately used ideas or statements of Sharon's as her own. In addition, she has taken credit for words and ideas that she did not think of herself. The ideas that she has presented are not original. Most likely, in developing her paper, she has not given any credit to Sharon for her work. Nancy has stolen something from Sharon, her creativity and intelligence. This is an act that should not go ignored. Nancy is clearly committing an act of academic dishonesty. She has cheated; not only herself from the knowledge she may have acquired by doing the research herself, but also her professor. Even if her professor had never found out, she still had lied in handing in someone else's work. I realize that there will be some people who disagree with me on whether Nancy has committed an act of plagiarism. Some will argue that Nancy didn't plagiarize because Sharon consented to Nancy using the paper. Despite the fact that Sharon voluntarily gave Nancy permission to use the paper, she still copied from it. Another possible argument in opposition to my position may be that it wasn't plagiarism because Nancy didn't copy from a respected source such as an encyclopedia or dictionary. Yet, when the definition is applied, Nancy has tried to pass of words or ideas that are not her own without giving credit to the author. In other words, she has plagiarized. It is vague as to how much Nancy actually used "to develop" her paper. Yet, the amount that she took from Sharon is immaterial; she actually used Sharon's ideas. I believe it is evident that Nancy was wrong in what she did. If new information is discovered in this case, specifically if Nancy did in some way give credit to Sharon as her source for the paper, then I will reexamine my position. However, at this time I feel that Nancy has plagiarized Sharon's paper and as a


result, disciplinary action should be taken to discourage her and others at this college from repeating this type of behavior. --Jamie Drula (used with permission) ___________________________________ Works Cited “Plagiarism.” Merriam Webster's Collegiate Dictionary. 10th ed. 1993. "Plagiarism.” Academic Writing at WFU. 1999. Wake Forest University. 7 Dec. 1999.

9. One day out of frustration your roommate throws a full plate of mashed potatoes against the wall of the room, where, amazingly, it sticks. You get up to remove the plate and potatoes from the wall. “Leave it,” your roommate insists. “It says something. It’s art.” “It’s garbage,” you reply. Who is right? My roommate is wrong; the mess he has created is indeed garbage. There is no possible way I am going to allow those potatoes on our wall. Art, as defined in Merriam-Webster’s online dictionary, is “the conscious use of skill and creative imagination especially in the production of aesthetic objects” and “the works so produced” (“Art,” Merriam). The American Heritage Dictionary adds that art “is human effort to imitate, supplement, alter, or counteract the work of nature.” It is “the conscious production or arrangement of sounds, colors, forms, movements, or other elements in a manner that affects the sense of beauty, specifically the production of the beautiful in a graphic or plastic medium is art.” The term “art,” the dictionary continues, also refers to “a field or category of art, such as music, ballet, or literature” (“Art,” American). Art, then, is the deliberate (or conscious) use of skill and imagination to make something new that affects our sense of beauty. Art is painting, photography, drawing, sculpture, architecture, music, and dance. “La Guernica” by Picasso is art. The Williamsport Philharmonic, CATS, The Nutcracker, the Eiffel Tower, and Load by Metallica are all art. All of these productions, whether we like them or not, are intentionally created to appeal to us and affect us in some way. The key here is intention. Given the definition of art, it is very clear that a piece of art must be intentionally and consciously produced. By just throwing the plate against the wall out of frustration, my roommate shows that he had no intention of the plate sticking and forming a piece of “art.” This mess on the wall may very well draw emotion to a viewer. However it was not deliberately created in an “effort to imitate, supplement, alter, nor counteract the work of nature.” The throwing of the plate against the wall was not a conscious use of skill in the order to produce an aesthetic object anymore than an elephant with a paintbrush in its trunk creates “art” when it slaps paint on a canvas. The potatoes were not deliberately


arranged in a certain order and thus show no conscious use of a medium. By putting no conscious or intentional effort for the plate on the wall, it cannot be ruled as art. --David Boyer (used with permission) _____________________________ Works Cited “Art.” Merriam-Webster’s Collegiate Dictionary. Online. 2001. “Art.” The American Heritage Dictionary of the English Language. Fourth Edition. Online. 2000. III. 1. Stipulative 2. Lexical 3. Persuasive 4. Precising 5. Stipulative 6. Precising 7. Lexical 8. Stipulative 9. Precising 10. Persuasive

11. Persuasive 12. Precising 13. Lexical 14. Stipulative 15. Persuasive 16. Lexical 17. Precising 18. Persuasive 19. Lexical 20. Precising

IV. 1. Enumerative 2. Synonymous 3. Etymological 4. Subclass 5. Genus and difference, and synonymous 6. Synonymous 7. Ostensive 8. Enumerative 9. Synonymous 10. Genus and difference, and synonymous

11. Etymological 12. Ostensive 13. Synonymous 14. Synonymous 15. Subclass 16. Etymological 17. Ostensive 18. Ostensive 19. Synonymous 20. Etymological


V. 1. Too broad 2. Circular 3. Slanted 4. Lacking in context 5. Too narrow 6. Non-essential meaning 7. Circular 8. Too obscure (Also too narrow.) 9. Slanted 10. Lacking in context

11. Slanted 12. Circular 13. Too broad 14. Figurative 15. Non-essential meaning 16. Slanted 17. Lacking in context 18. Too broad 19. Too obscure 20. Figurative

Exercise 4.3 I. The more creative students in your class will enjoy this exercise. The more literal minded may find the exercise taxing and unenlightening. If you don’t want to spend the time in small groups, the exercise works well as a short class discussion, perhaps at the end of the period, when you have a few moments to discuss the practical applications of the day’s lesson on language. Because the first part of the exercise asks students to invent names for vehicles, you might share with the students Marianne Moore’s correspondence with the Ford Motor Company. She was asked to come up with a name for their newest car in 1950. She humorously suggested such things as The Magigravue, The Turcotingo, and The Utopian Turtletop. Ford choose instead “Edsel.” (You can find the story at several good sites: ( and Modern American Poets ( II. The second part of the exercise invites observations on the building and naming of suburban housing developments and shopping centers. Some students will enjoy the opportunity to comment on how such property—which is often bland, unremarkable, and identical in its architecture and design—is made more attractive and “unique” through labeling. As an added topic for discussion in this section, one that works very well for driving home the chapter’s point about the emotive quality of language, ask your students about their names and the names of their siblings, children, or pets. Ask students whether they’ve ever had to choose a name for a child or a pet. Ask them what went into the decision and what effect they hoped to achieve. Ask them about their own names: Are they happy with them? Do their names say anything about them as individuals? When they hear certain names, how do they respond? You might share with them the following lists. The first provides the most popular names for babies born in 2000 and the most


popular baby names in the 1880’s. The second provides the given names of some celebrities and their more familiar stage name. Baby names (Source: 2000 Girls 1. Hannah 2. Emily 3. Sarah 4. Madison 5. Brianna 6. Kaylee 7. Kaitlyn 8. Haley 9. Alexis 10. Elizabeth


Boys Michael Jacob Matthew Nicholas Christopher Joseph Zachary Joshua Andrew William

Girls Mary Anna Elizabeth Margaret Minnie Emma Martha Alice Marie Annie, Sarah

Boys John William Charles George James Joseph Frank Henry Thomas Harry

Celebrity Names Better Known As Woody Allen Fred Astaire Pat Benatar Tony Bennett Mel Brooks George Burns Nicholas Cage Michael Caine Alice Cooper David Copperfield Elvis Costello Tom Cruise Rodney Dangerfield James Dean John Denver Kirk Douglas Bob Dylan Whoopi Goldberg Cary Grant Charlton Heston Billie Holiday Elton John Ralph Lauren

Born Steward Konigsberg Frederick Austerlitz Patricia Andrzejewski Antonio Dominic Benedetto Melvin Kaminsky Nathan Birnbaum Nicholas Coppola Maurice Joseph Micklewhite Vincent Furnier David Kotkin Declan Patrick MacManus Thomas Mapother IV Jacob Cohen James Byron John Henry Deutschendorf Issur Danielovitch Robert Allen Zimmerman Caryn Johnson Archibald Alexander Leach John Charles Carter Eleanora Fagan Reginald Kenneth Dwight Ralph Lipshitz


Jerry Lewis Sophia Loren Elle McPherson Madonna Cher Malcolm X Walter Matthau Meat Loaf George Michael Marilyn Monroe Demi Moore Muddy Waters Prince Ginger Rogers Roy Rogers Jane Seymour Martin Sheen Sting John Wayne Stevie Wonder

Joseph Levitch Sofia Scicolone Eleanor Gow Madonna Louise Veronica Ciccone Cherilyn Sarkisian Malcolm Little Walter Matuschanskavasky Marvin Lee Adair Georgios Kyriacos Panayiotou Norma Jean Mortenson Demetria Guynes McKinley Morganfield Prince Rogers Nelson Virginia Katherine McMath Leonard Slye Joyce Penelope Wilhemina Frankenberg Ramon Estevez Gordon Sumner Marion Michael Morrison Steveland Judkins

Exercise 4.4 I. This is another exercise that asks students to think about how they use language and to think about the differences between similar words. Careless choices in diction lead to misunderstanding and frustration. The point of this exercise is not to find the correct word or to provide a list of perfect synonyms but to provide similar words that have obvious or subtle differences in meaning. Students are being encouraged in this exercise to think about the richness and variety in the English language and to commit themselves to the hard work of selecting precise and accurate words. In a scene in the film Twelve Angry Men, Juror #4 reports that the defendant claimed to have been “slapped” by his father. Juror #4 is reminded by another juror that the young man claimed to have been “punched.” Juror #4 settles on “hit.” Some students want to say there is no difference. One approach to the assignment is to have students think of as many “synonyms” as they can for a term and then to discuss some of the differences in denotation and connotation among the words listed. Obviously, students with good vocabularies will participate more enthusiastically. 1. This one is done as an example in the text. 2. Possible choices: exclaimed, intoned, declared, insisted, whispered, mumbled, declared, cried, stated, uttered, asserted, confessed, blurted, admitted. Some words suggest the speaker’s sense of freedom, whereas others suggest


trepidation or anxiety. 3. Possible choices: demanded, requested, begged, implored, pleaded. Most words that students choose for this item will portray a demanding child. To describe the child as excited or pleasant, the word exclaimed might be used (squealed?), or the word said could be qualified: the child said optimistically, excitedly, hopefully, gleefully, and so forth. 4. Possible choices: begged, pleaded, requested, implored, insisted, demanded, screamed, Begged, pleaded, and implored suggest that the speaker is dependent on the listener or that she is desperate. Demanded shows that she has more power over the listener, making “please” in the sentence merely courteous or perhaps sarcastic. 5. Possible choices: ogle, stare at, eyeball, eye up, watch, check out, scrutinize. Most of these words are accusatory, but students could be asked to supply words with more positive connotations (behold comes to mind). If students offer choices such as notice or see, you can talk about whether these words accurately capture the apparent intent of the speaker. Students could be asked to discuss tone and how tone can change the meaning of the sentence as it is stated in the text: “Did you look at that woman?” This and other items in this exercise offer a chance to discuss how a word’s connotation and meaning can be altered by context. The word right in a court transcript can have a variety of meanings depending on how it was said. 6. Possible choices: demolished, destroyed, broke, cracked, snapped, shattered, scratched. Although a cracked CD is a destroyed CD, students can discuss when it is necessary or appropriate to be specific. 7. Possible choices: gripped, grabbed, clutched, seized, squeezed. Gripped connotes aggression or dominance; clutched suggests fear or protection. 8. Possible choices: nuts, crazy, insane, out of your mind, not thinking clearly, unwise, stupid, imprudent, thoughtless, irrational, stupid, foolish, silly, reckless. Some of these choices (not thinking clearly, foolish, imprudent) are more forgiving than others. Some (insane, crazy) might be insensitive. 9. Possible choices: committed to, devoted to, dedicated to, obsessed with. Students might be asked to comment on the difference between believing in a cause and being devoted to it. 10. Possible choices: cold, hard-hearted, apathetic, callous, insensitive, unsympathetic. These words are all close in meaning, but callous might imply a roughness developed after many disappointments, and apathetic suggests indifference and a lack of concern.


11. Possible choices: lazy, contemplative, idle, lethargic, sedentary, unmotivated, apathetic, passive, laid-back, unhurried, a slacker, workshy (British). 12. Choices might be endless: mad, furious, outraged, incensed, irritated, livid, irate, enraged, outraged, infuriated, cross, pissed off, apoplectic, inflamed, upset, annoyed, irritated, riled up, bothered, exasperated, frustrated. 13. Possible choices: accepted, okayed, endorsed, praised, admired, celebrated. These words all have different meanings, but they share the notion of approval. However, some of the words (praised, celebrated) suggest something far more positive than others (accepted, okayed). 14. Possible choices: selfish, self-centered, egotistical, egocentric, greedy, conceited, vain, inconsiderate, insensitive, narcissistic, thoughtless, uncharitable, unkind, uncaring, careless, insensitive, discourteous. 15. Possible choices: shocking, indecent, unacceptable, offensive, out of place, unethical, unsuitable, reprehensible, rude, improper, abnormal, unsuitable, unconventional, unorthodox, unusual, unseemly, indelicate. II. 1. Emotive words and phrases in the advertisement include charming, cozy (code for small?), older neighborhood, lower-level recreation room (basement?), modern, tender loving care (needs lots of work?). All these words are used to create a warm and receptive attitude in the prospective buyer. 2. Almost all of the words are emotive. You might point out that some of the words (mature, petite,) might also be euphemisms. An interesting variation of this exercise involves having students describe themselves for a dating service, using only selected words that will generate the most positive emotional responses. Or have them describe themselves to a job agency. Alternatively, have them list four or five personal traits they know they need to improve (e.g., "loves to watch professional wrestling") and have the students rewrite the phrases with a positive spin. This exercise, naturally, dovetails well with the following section on euphemisms. And students enjoy writing euphemistically about themselves. 3. Emotive words include traipsed, disrupt, indoctrinate, circumventing, hovered, spread, gospel, self-indulgent, terrorism. 4. This passage does not have the obvious kinds of emotive language that critical thinking students get accustomed to looking for—the blatant emotional appeals, sarcastic slanting and name-calling characteristic of the preceding passages. I think it’s important to let students know that some writing (such as you find in literary essays), contains more subtle emotional appeals. The emotive words and phrases in this passage include family herd, grandma’s practiced eye, desperate families, flooded, seeking, bundle, toddlers, hang, unswaddle, species. Students might be asked how Kingsolver carefully sets up her final sentence with a subtle, emotionally charged


passage. They might also comment on whether the historical description of women’s work is relevant to the point suggested in the final sentence. I’m not sure it is. 5. There are almost too many emotional appeals to count. Here are just a handful: world split into two vast, increasingly hostile armed camps; impotency; invade our shores; traitorous actions; infested with Communists; the graft, the corruption, the dishonesty, the disloyalty, the treason; emotional hang-over; moral lapse; apathy to evil; cloak of numbness; whole sorry mess of twisted, warped thinkers; swept from the national scene; new birth of national honesty and decency. III. We've used encyclopedia articles on John Brown to show that even supposedly objective sources are filled with emotive language. Here are just the opening paragraphs of entries on John Brown in several encyclopedias: Collier’s, 1997 BROWN, JOHN (1800-1859), one of the most extreme and violent of American abolitionists, was born on May 9, 1800, at Torrington, Conn. The son of Owen Brown and Ruth Mills Brown, he was descended from a Mayflower passenger on his father's side. At the age of five he was taken to Hudson, O., where he spent the rest of his childhood and youth. After a rudimentary education, he began working in his father's leather tannery and then went into business on his own. A restless man, eager to try his luck anywhere, Brown worked for over twenty-five years in leather tanning and the wool business in at least ten different locations, ranging from Richmond, Pa., and Springfield, Mass., in the east to Akron, O., in the west. His ventures did not prosper, and in 1842 he was declared bankrupt while living in Richfield, O. He then joined with Simon Perkins of Akron in a new company selling wool, moving to Springfield to take charge of the firm's office there. Brown's business career ended in 1849 with the dissolution of his partnership with Perkins. Litigation continued for several years thereafter. Grolier’s, 2000 BROWN, JOHN (1800-1859). American abolitionist who took direct action to free slaves by force. He was convicted of treason, conspiracy, and murder following his raid on Harpers Ferry, Va. (now W.Va.), Oct. 16-18, 1859, and was executed on December 2. The most controversial of the abolitionists, Brown was regarded by some as a martyr and by others as a common assassin. Still others questioned his sanity. Brown's name often is linked in the public mind with that of William Lloyd Garrison, as an extremist. Unlike Brown, however, Garrison was a pacifist. Northern resistance to slavery found leaders with radically different methods. The Great Soviet Encyclopedia, 1975


BROWN, JOHN. Born May 9, 1800, in Torrington, Connecticut; died Dec. 2, 1859, in Charles Town, Virginia. Fighter for the emancipation of the Negro slaves in the USA. One of the leaders of the left wing of the abolitionist movement. Author of antislavery pamphlets. Brown participated in the activity of the so-called underground railroad. In 1855-56 he organized an armed struggle against slaveholders in Kansas. He worked out a plan for the establishment of a free republic in the Allegheny Mountains as a base for the struggle against slavery, and he composed a draft for its democratic provisional constitution. Carrying out his plan, Brown captured the government arsenal in Harpers Ferry (in the slaveholding state of Virginia) on Oct. 16, 1859, with a band of 18 people (including five Negroes). The band was surrounded by troops and almost completely annihilated. Two of Brown's sons were killed, and he was himself seriously wounded. In accordance with a court sentence Brown was hanged in Charles Town. Brown's uprising, which immediately preceded the Civil War of 1861-65, was an open challenge to slavery. His name became a symbol for revolutionary action and the struggle for the rights of the Negro people. Chambers, 1973 BROWN, JOHN (1800-59), American abolitionist, was born in Connecticut on 9 May 1800 of a family in which there was a marked strain of insanity. He spent 50 years trying to make a success is business and failed. He was likewise interested in the welfare of Negroes in slavery and became a fanatic on the subject of abolition, believing himself called of the Lord to serve the cause of freedom. He went out to Kansas in the early days of its settlement and engaged in land speculating, cattle trading and the political feuding which were all closely intertwined. He participated in some acts of violence, notably the brutal killing of five political opponents at the Potawatomie massacre in May 1856. Brown had friends among eastern philanthropists who were attracted by his great zeal. They gave money to develop a plan to free the slaves by force. In 1858 he conducted a raid on a Missouri farmer and ran off slaves to Canada. Then he began his last effort. He would invade slave states and establish refuges in the mountains, first in Virginia, and invite and bring slaves thither. His hope was that this wholesale liberation would cause Virginia to abolish slavery. Then he would go into other regions and repeat his exploits. He prepared for his first raid in the summer of 1859 with financial support from prominent philanthropists; it seems incredible that they should not have known what Brown was planning. His raid of 16 Oct. 1859 upon Harpers Ferry where a government arsenal and rifle manufactory were located was easily stopped. No one joined him and his small force of 20 was killed or captured. He was tried, and hanged on 2 Dec. 1859. Britannica, 1997 BROWN, JOHN (b. May 9, 1800, Torrington, Conn., U.S.-d. Dec. 2, 1859, Charlestown, Va.), militant American Abolitionist whose raid on the federal arsenal at Harpers Ferry, Va., in 1859 made him a martyr to the anti-slavery cause and was instrumental in heightening sectional animosities that led to the American Civil War (1861-65).


Moving about restlessly through Ohio, Pennsylvania, Massachusetts, and New York, Brown was barely able to support his large family in any of several vocations at which he tried his hand: tanner, sheep drover, wool merchant, farmer, and land speculator. Exercise 4.5 Some students will try to see euphemisms and emotive language as two separate issues. We try in this part of the chapter to show that euphemisms are a form of emotive language used to deliberately hide the truth, so that someone who says that he was a bit of a radical in college might be speaking accurately about his activities, or he might be trying to put a positive spin on his delinquency. In either case, the phrase "bit of a radical" has emotive meaning, but when it is used to hide the truth, it falls into the category of euphemism. When deciding whether a word or phrase is euphemistic or politically correct, you might ask, Does this word accurately label the objective action or person it refers to? In other words, students might list the actions of several college students: Before the game, Adam stole State’s mascot, scratched his fraternity’s letters into the walls of tavern restrooms, and tore down a goalpost; Betty joined the Young Communists Club and protested the bookstore’s selling of non-union made clothing; Carla burned down the president’s home. Who, if anyone, deserves the term radical or delinquent? In examining the euphemisms and politically correct terms in Exercise 4.5, you might ask students the same sort of question: is, for example, convict a more accurate term than socially separated for someone who is serving time in prison? Some enterprising students might look up the words on the left side of the page to see if their etymology and lexical meanings provide any insight into their accurate use. Convict comes from the same Latin root from which we get convince: convincere, meaning to prove wrong, from vincere, to overcome. So a convict is someone who has been proven wrong (or guilty) in a court of law. Socially separated, which could refer to an elderly shut-in, is not accurate when describing a prisoner who has been tried and convicted. So convict is the better choice. Socially separated is inaccurate, euphemistic, and perhaps politically correct.


Chapter 5: Logical Fallacies-1 Exercise 5.1 1. Positively relevant 2. Positively relevant 3. Irrelevant 4. Irrelevant 5. Positively relevant 6. Positively relevant 7. Negatively relevant. 8. Positively relevant 9. Irrelevant 10. Positively relevant (Although the premises don't provide evidence for God's existence, they do provide prudential, or self-interested, reasons for belief in God. Whether these prudential reasons are properly convincing is, of course, another question.) 11. Positively relevant 12. Positively relevant 13. The first premise is negatively relevant, and the second premise is positively relevant 14. Positively relevant (Because many Chinese girls are aborted or put up for foreign adoption, there are more boys than girls in China.) 15. Positively relevant (In a democracy, the fact that most citizens want something to be legal, does generally provide at least some reason why that thing should be legal.) Exercise 5.2 I. 1. Bandwagon argument 2. Personal attack 3. Appeal to pity 4. Straw man 5. Look who's talking 6. Equivocation 7. Begging the question 8. Attacking the motive 9. Scare tactics 10. Two wrongs make a right 11. Straw man 12. No fallacy 13. Equivocation 14. Bandwagon. 15. Look who's talking 16. No fallacy

17. Red herring 18. Appeal to pity 19. No fallacy 20. Scare tactics 21. Personal attack 22. Straw man 23. Attacking the motive 24. Two wrongs make a right 25. Red herring 26. No fallacy or appeal to pity 27. Scare tactics 28. Attacking the motive 29. Equivocation 30. Begging the question 31. Bandwagon argument 32. Look who's talking


33. Two wrongs make a right 34. Bandwagon argument 35. Straw man 36. Equivocation

37. Red herring 38. No fallacy 39. Personal attack 40. No fallacy

II. This is a good active learning exercise. Some of the examples students come up with tend to be pretty funny. III. Students find this exercise challenging, and many of the examples they come up with will not in fact be examples of the fallacies they allege. Nevertheless, the exercise is useful in getting students to think about fallacies of relevance and to begin to be on the look-out for them in real-life contexts.


Chapter 6: Logical Fallacies-2 Exercise 6.1 I. 1. Inappropriate appeal to authority 2. Questionable cause 3. Loaded question 4. Inappropriate appeal to authority 5. Appeal to ignorance 6. Inconsistency 7. Hasty generalization 8. Inconsistency 9. False alternatives. 10. Inappropriate appeal to authority 11. Slippery slope 12. Appeal to ignorance 13. Weak analogy 14. No fallacy 15. Loaded question 16. Inappropriate appeal to authority 17. No fallacy. (The analogy is a good one.) 18. No fallacy (assuming that the risk of avalanche is real) 19. No fallacy

20. Questionable cause 21. Slippery slope 22. Hasty generalization 23. False alternatives 24. Weak analogy 25. Inappropriate appeal to authority 26. No fallacy 27. Loaded question 28. Inconsistency 29. Questionable cause 30. Inappropriate appeal to authority 31. False alternatives 32. Weak analogy 33. No fallacy 34. Weak analogy 35. Hasty generalization 36. Appeal to ignorance 37. Hasty generalization 38. Weak analogy 39. No fallacy 40. Slippery slope

II. 1. 2. 3. 4.

Loaded question Questionable cause Weak analogy False alternatives (assuming that an argument is being given) 5. Weak analogy 6. Look who's talking and personal attack; also possible inconsistency 7. False alternatives 8. Weak analogy 9. Begging the question 10. Questionable cause 11. Two wrongs make a right 12. Weak analogy 13. Equivocation 14. Weak analogy

15. Personal attack 16. Hasty generalization 17. Slippery slope 18. Weak analogy; possible slippery slope 19. False alternatives 20. Personal attack 21. Slippery slope 22. Hasty generalization 23. Personal attack; possible red herring 24. Questionable cause 25. Weak analogy 26. Slippery slope 27. Ad hominem 28. Appeal to ignorance 29. Inconsistency


30. Questionable cause III. Students enjoy this exercise, and it is a good source of examples for the game in Exercise 6.1., Part VI. IV. This exercise works well with stronger students. With weaker students, you’ll find that most of the examples they collect are either not fallacies at all or not the fallacies they think they are. Still, treasure hunts may be worthwhile, even if most of the "treasure" brought back is fool’s gold. V. We encourage you to try this exercise; it's always a hit with our students. We've found that students do much better spotting the fallacies if they are assigned an individual juror to watch. Evidence Against the Accused 1. The old man downstairs claims (a) he heard the accused yell, "I'm gonna kill you!" followed by the sound of a body hitting the floor, and (b) he saw the accused running down the stairs fifteen seconds after the murder. 2. The woman across the el-tracks claims she saw the accused stab his father through the windows of a passing el-train. 3. The knife was identified as the defendant's by several witnesses and was allegedly one-of-a-kind. 4. The accused had a weak alibi. He couldn't remember the names of the movies or who played in them. Also, he claims, implausibly, that the knife fell through a hole in his pocket on his way to the movies. 5. The accused had a motive: He had regularly been beaten up by his father, and he had been "hit" by his father earlier that evening. 6. The accused had a prior record (including two arrests for knife fighting).


How This Evidence Was Later Weakened or Undermined by Critical Thinking Versus 1a: The el-train was making too much noise for the witness to have reliably identified the defendant's voice. Versus 1b: Juror #8 proved that it would have taken the witness at least 41 seconds (actually 31 seconds: time it!) to have walked from his bedroom to the front door--not the fifteen seconds the witness claimed. Moreover, there are general reasons for doubting the credibility of the old man’s testimony. As Juror #9 pointed out, the witness apparently wasn't very observant (he wore a torn jacket to court). Also, according to Juror #3, he was confused much of the time on the stand. Versus 2: As Juror #9 pointed out, the woman had marks on her nose, indicating that she wore glasses. Since the woman presumably wasn't wearing her glasses at the time of the murder, it's doubtful she could have clearly identified the defendant. Versus 3: Juror #8 bought another knife just like the murder weapon at a pawn shop just a few blocks from the defendant's apartment; this proved that the knife wasn't unique. Moreover, why would the accused have left the knife sticking in his father's chest (taking care to wipe off any fingerprints) and then come back to the apartment, knowing that the murder had likely been detected and that the knife could be identified as the one he had just bought? Versus 4: As Juror #8 showed, it's not always easy to remember details when one is under great emotional stress. Versus 5: As Juror #8 pointed out, it's not clear how strong a motive this was, given the defendant's long history of physical abuse. Versus 6: On the other hand, as Juror #5 pointed out, someone as handy with a knife as the accused probably would have gone for his victim underhanded. Fallacies Committed by the Jurors Juror #1: Foreman and high school football coach (Martin Balsam) No fallacies. Juror #2: Bank clerk (John Fiedler) Appeal to ignorance: (“I just think he’s guilty. . . . Nobody proved otherwise.”)


Juror #3: Head of messenger service (Lee J. Cobb) Inconsistency: ("You can throw out all the other evidence. The woman saw him do it. . . . "What about all the other evidence? The knife? The whole business?") Inconsistency: (How could he be positive about anything? Half the time he was confused.) Attacking the person: ("You lousy bunch of bleeding hearts, you're not going to intimidate me") Attacking the person: ("You keep coming in with all these bright sayings. Why don't you send them into a paper? They pay three dollars apiece.") Red herring: ("You can't prove that he didn't get to the door!") (Also possible appeal to ignorance.) Red herring: ("How do you know she didn't have [her glasses] on?") Weak analogy: ("What is this, underprivileged brother week or something? Why don't you drop a quarter in his collection box?") Juror #4: Stockbroker (E.G. Marshall) No fallacies. Juror #5: Mechanic (Jack Klugman) No fallacies. Juror #6: Housepainter (Edward Binns) Scare tactics: ("You say stuff like that to him again, I'm gonna lay you out.") (Not a clear-cut case, because it's not obvious the housepainter is rejecting any argument offered by Juror #3) False alternatives: ("If you don't have a motive, where's your case?") Juror #7: Salesman Bandwagon argument: ("What's there to talk about? Eleven of us in here think he's guilty.")


Weak analogy: ("Supposing we're wrong! Supposing this whole building should fall on our heads. You can suppose anything.") Weak analogy: (How do you like this guy? It's like talking into a dead phone." Hasty generalization: ("I'm telling you they're all like. They come over here running for their life, and before they can take a deep breath, they're telling us how to run the show.") False alternatives: (What're you get out of this--kicks? Or did somebody bump you on the head one time, and haven't gotten over it?) Juror #8: Architect (Henry Fonda) Appeal to pity: ("This kid's been kicked around all his life. . . . I just think we owe him a few words, that all.") (Not a clear-cut case, because it's not obvious the appeal is irrelevant in this context.) Juror #9: Old Man (Joseph Sweeney) No fallacies. Juror #10: Garage owner (Ed Begley) Bandwagon argument: ("Boy oh boy, there's always one.") Bandwagon argument: ("How come you're the only one in this room who wants to see exhibits all the time?") Hasty generalization: ("They're no good. Not a one of them is any good." "They're real big drinkers, all of them." "The kids who crawl out of them are real trash." "You can't believe a word they say." "Human life don't mean as much to them as it does to us." "Most of 'em, it's like they have no feelings." "They're born liars." "They don't know what the truth is. "Those people are dangerous. They're wild.") Inconsistency: ("You can't trust a word they say"--but he believes the woman's testimony, even though she's one of "them," too.) Attacking the person: ("Oh, stop being a kid, will you.") Attacking the person: ("He's the fifteenth assistant or something. What does he know about it?")


Questionable cause: ("You know how these people lie. It's born in them.") Juror #11: Watchmaker (George Voscovec) No fallacies. Juror #12: Ad man (Robert Webber) No fallacies. VI. Students have fun with this exercise. Check the Additional Resources section of this manual for examples that can be used in the game.


Chapter 7: Analyzing Arguments Exercise 7.1 1.  Bertie probably isn't home.  His car isn't in the driveway, and  there are no lights on in his house.

2.  No members of the volleyball team like hip hop.  Andrea is a member of the volleyball team. So,  Andrea doesn't like hip hop.

3.  Don’t copy off Sturdley’s exam.  He’s one of the worst students in class.  My roommate told me he’s bombed every test this semester.

4. Affirmative action in higher education is morally justifiable, because  it compensates for past discrimination,  provides valuable role models for women and minorities, and  promotes multicultural understanding.


5.  Either this is my car or it's Sandy's car.  If it is my car, then the key should fit in the lock. But  my key doesn't fit in the lock. So,  this is Sandy's car.

6.  Wexford College is a really great college.  The students are friendly.  The faculty really care about the students.  The campus is beautiful, and  the athletic facilities are great.

7.  Only three people could have stolen the CD: Danny, Stacy, or Patrick. But  Stacy couldn't have stolen the CD, because  she was out riding her bike.  Patrick couldn't have stolen the CD, because  he was at a friend's house. Therefore,  Danny must have stolen the CD.

8.  Something is a square only if it is a rectangle. But  this isn't a rectangle. Look,  it only has three sides, and  some of the sides aren't even straight. So,  this can't be a square.


9.  Lasse speaks fluent Finnish.  It is likely, then, that Lasse was born in Finland.  Anyone born in Finland is a Finnish citizen. So  Lasse is likely a Finnish citizen. Finnish citizens are entitled to European Union travel privileges. So  Lasse is probably entitled to European Union travel privileges.

10. Several states have abolished the insanity defense against criminal responsibility.  This may be popular with voters, but it is morally indefensible.  Insanity removes moral responsibility, and  it is wrong to punish someone who is not morally responsible for his crime. Moreover, it is pointless to punish the insane, because  punishment has no deterrent effect on a person who cannot appreciate the wrongfulness or criminality of his or her actions.


11.  Jeremiah is a bullfrog.  It follows – since  all bullfrogs are amphibians – that Jeremiah is an amphibian.  All amphibians can drink wine.  So Jeremiah can help me drink my wine.

12.  It's foolish to smoke cigarettes.  Smoking is expensive,  unhealthy, and  obnoxious to many nonsmokers.  I wouldn't date anyone who smokes cigarettes.

13.  If today is Saturday, then tomorrow is Sunday.  If tomorrow is Sunday, then we'll be having pasta for dinner.  If we'll be having pasta for dinner, then I should pick up some red wine today, since  in this state wine can be purchased only at liquor stores, and  the liquor stores are closed on Sundays.  Today is Saturday. Therefore,  I should pick up some red wine today.

14.  It makes no sense to ask God for things in prayer.  The thing you ask for is either good or it is not.  If it is good, then God will do it anyway.  If it is not, then he won't.  In neither case, can your prayer make any difference.


15.  If Amy isn't dating Sturdley, then she's dating Mel or Steve.  Amy isn't dating Sturdley, since  she doesn't date anyone who uses drugs, and  Sturdley sniffs glue practically every weekend. Thus,  Amy is dating Mel or Steve. However,  Amy won't date anyone who isn't a football player, nor  will she date anyone who isn't goodlooking.  Both Mel and Steve are good-looking, but  Steve isn't a football player. Consequently,  Amy is not dating Steve. We can logically deduce, therefore, that (11) Amy is dating Mel.

Exercise 7.1 II. 1. Since  our feelings, desires, and preferences can be either beneficial or harmful, noble or ignoble, praiseworthy or damnable, and since  they can be either in harmony or in conflict with other people's feelings, desires, and preferences,  they are obviously not accurate tools for analysis of moral issues or trustworthy guidelines to action.


2.  Suppose you had one sheep which fell into a ditch on the Sabbath; is there one of you who would not catch hold of it and lift it out? And  surely a man is worth more than a sheep!  It is therefore permitted to do good on the Sabbath.

3.  Wealth is not sought except for the sake of something else, because  of itself it brings us no good, but only when we use it, whether for the support of the body or some similar purpose. Now  the highest good is sought for its own sake, and not for another’s sake. Therefore  wealth is not man’s highest good. (St. Thomas Aquinas, Summa Contra Gentiles).

4.  School tests should be abolished.  Tests introduce competition where it does not belong.  They deny the individuality of students' talents and interests  They degrade education by encouraging passivity, mindlessness, and triviality. Finally,  they send the wrong messages about what is valuable in education and in life.


5.  The rule of equal incomes is socially impracticable.  It would deter the great majority of the more efficient from putting forth their best efforts and turning out their maximum product. As a consequence,  the total volume of product would be so diminished as to render the share of the great majority of persons smaller than it would have been under a rational plan of unequal distribution.

6.  Many that live deserve death. And  some that die deserve life.  Can you give it to them? Then  do not be too eager to deal out death in judgment. For  even the wise cannot see all ends.

7.  Everything eternal is necessary. But  whatever God wills, he wills from eternity, for otherwise  His will would be mutable. Therefore,  whatever He wills, He wills necessarily.

8.  Testing at the national level is indicated;  we are all aware of the abysmal education of too many young people, especially in certain areas and certain schools.  Such people tend to become narrow-minded, ignorant and hateful, and contribute little to advancing the highest ideals of which we are capable.  National testing can help to devote extra attention to such places.


9.  If a body moves, either it must move in the pace where it is or in the place where it is not. But  it cannot move in the place where it is, and  it cannot move in the place where it is not. Therefore,  no body can move. (Zeno, “Paradoxes.”)

10.  Education implies teaching.  Teaching implies knowledge.  Knowledge is truth.  The truth is everywhere the same. Hence  education should be everywhere the same.

11.  All humans have equal positive value.  There is no morally relevant difference between humans and some animals (such as mammals). Therefore,  some animals have equal positive worth with humans.  Moral rights derive from the possession of value. Since  humans have rights (to life, not to be harmed, and so forth),  animals have those same rights.

12.  True-false and multiple-choice tests have well-known limits.  No matter how carefully questions are worded, some ambiguities will remain.  The format of the questions prohibits in-depth testing of important analytic skills.  Students can become so "test savvy" that objective tests measure test-taking skill as much as subject-matter content.


13.  Planetary exploration has many virtues.  It permits us to refine insights derived from such Earth-bound sciences as meteorology, climatology, geology and biology, to broaden their powers and improve their practical applications here on Earth.  It provides cautionary tales on the alternative fates of worlds.  It is an aperture to future high technologies important for life here on Earth.  It provides an outlet for the traditional human zest for exploration and discovery, our passion to find out, which has been to a very large degree responsible for our success as a species. And  it permits us, for the first time in history, to approach with rigor, with a significant chance of finding out the true answers, questions on the origins and destinies of worlds, the beginnings and ends of life, and the possibilities of other beings who live in the skies—questions as basic to the human enterprise as thinking is, as natural as breathing.

14.  Creation has no place in a science class because  it is not science. Why not? Because  creationism cannot offer a scientific hypothesis that is capable of being shown wrong.  Creationism cannot describe a single possible experiment that could elucidate the mechanics of creation.  Creationism cannot point to a single prediction that has turned out to be right, and supports the creationist case.  Creationism cannot offer a single instance of research that has followed the normal course of scientific inquiry, namely, independent testing and verification by skeptical researchers.

15.  Nonhuman animals lack linguistic capacity, and, for this reason,  lack a mental or psychological life. Thus,  animals are not sentient.  If so, of course, they cannot be


caused pain, appearances to the contrary. Hence,  there can be no duty not to cause them pain.

16.  All students should study a foreign language.  It improves mastery of English.  It helps to avoid cultural provincialism by expanding the cultural experience of students.  It is useful for travel and commerce.  It makes it possible to do advance work in a foreign language, including the study of the major literary works in that language. Finally,  the ability to read, speak, and think in a second language is a source of pleasure and satisfaction even if this language is not used for travel and business and even if it does not become a field of further study.

17.  No belief is justified if it can be fully explained as the result of natural causes.  If materialism is true, then all beliefs can be explained as the result of irrational causes. Therefore  if materialism is true, then no belief is justified.  If no belief is justified, then the belief “materialism is true” is not justified. Therefore  materialism should be rejected. (Victor Reppert, C.S. Lewis’ Dangerous Idea (slightly adapted)).

18.  A square must have exactly four corners, and  a circle must have exactly zero corners. So  a round square must have exactly four corners and simultaneously have


exactly zero corners. But  this is plainly impossible; hence  there cannot be a round square. (Erik J. Wielenberg, God and the Reach of Reason)

19.  Lefty Grove was the greatest pitcher of all time, period.  The one best indicator of a pitcher's ability is his ERA, and  Lefty grove led leagues in earned run average nine times.  No one else even approaches this record.  The second-best indicator of a pitcher's ability is his winning percentage. Guess what?  Grove also led the league in that more times than anyone else.

20.  Here is a gentleman of a medical type, but with the air of a military man.  Clearly an army doctor, then.  He has just come from the tropics, for  his face is dark, and  that is not the natural tint of his skin, as  his wrists are fair.  He has undergone hardship and sickness, as  his haggard face says clearly.  His left arm has been injured.  He holds it in a stiff and unnatural manner. Where in the tropics could an English doctor have seen much hardship and get his arm wounded? (11) Clearly in Afghanistan.

Exercise 7.2 1. Most Californians are friendly.


2. A need or complaint kept secret will never be addressed. 3. You shall not commit murder. 4. Human beings are the only rational animals on earth. 5. Don't worry about problems that can't be fixed. (Or: People don't worry about problems that can't be fixed.) 6. Only persons that are citizens from birth may be president. 7. Having a lot of money is not the secret to true happiness. 8. In case I don’t have another opportunity to wish you a nice holiday, I do so now. 9. All human beings are created with equal moral worth and equal basic rights. (This paraphrase is debatable, obviously.) 10. Because a well-regulated citizen militia is necessary to the security of a free state, the right of the individual citizens to keep and bear arms shall not be infringed. 11. People make light of hardships they’ve never personally experienced. 12. Regarding yesterday's e-mail from you, please note that there is no parking close to the convention center, because the Jefferson Street Parking Garage is closed for repairs. 13. Common sense tells us that long-established governments should not be changed without compelling reasons. That is why, as all experience shows, people tend to be willing to endure political abuses, while those abuses are tolerable, rather than correct them by abolishing the forms of government to which they are accustomed. But when a long series of abuses and injustices, all with the same purpose, makes clear that the government is attempting to establish a complete dictatorship, it is their right, it is their duty, to throw off the government and provide new safeguards for their future security. 14. Because human reason is so weak and uncertain, some people should simply be told what their duties are. Otherwise, they will make poor choices that may result in serious harm. 15. A person commits the crime of sexual misconduct in the first degree if he or she (1) has deviate sexual intercourse with another person of the same sex without that person's consent, (2) purposely subjects another person to sexual contact without that person's consent, or (3) purposely engages in conduct that would constitute nonconsensual sexual contact with another person except that the touching occurs through that person's clothing.


Exercise 7.3 I. 1. Missing premise: All Mazda Miatas are convertibles. 2. Missing conclusion: This Beetle is fuel efficient. 3. Missing premise: Blazers are not made by Ford. 4. Missing premise: This is not a Honda. 5. Missing premise: This is either a Camaro or a Firebird. 6. Missing premise: Minivans are roomy. 7. Missing premise (subconclusion): This is a Toyota. 8. Missing premise (subconclusion): This car doesn't get good gas mileage. 9. Missing conclusion: Either this is a Ford or it's a Mercury. 10. Missing premise: Some Fords are Rangers. II. 1. Missing premise: Most people from Singapore speak English. 2. Missing conclusion: Whatever is dangerous should be banned. 3. Missing premise: Most blondes are dumb. 4. Missing premise (subconclusion): It's not cold. Missing premise (subconclusion): It's not snowing. Missing conclusion: Uncle Fred will be coming over for dinner. 5. Missing premise: All Princeton graduates are smart. Missing premise: Anyone who is smart should be able to solve this logic problem in the time allotted. 6. Missing premise: I'm not rich. Missing premise: Bill Gates is the Chairman of Microsoft. 7. Missing premise: Today is Thursday. Missing premise: Zoe is not on the golf course. 8. Missing premise: Anything that comes to an end is meaningless. 9. Missing premise: If Bugsy became totally blind last year, then he didn't drive the getaway car. Missing premise (subconclusion): Bugsy didn't drive the getaway car. Missing premise (subconclusion): Sparky was not working for Bugsy. 10. Missing premise: Jay is a Hampton College student. Missing premise: Anyone who voted the straight Republican ticket in the last election and has a large poster of president George W. Bush in his dorm room is probably a Republican. Missing premise: Most Republicans favor a constitutional amendment banning abortion.


Exercise 7.4 1. 1. Asking the question “Will this be on the exam?” indicates that your main interest is in getting through the course with a good grade rather than in learning what the instructor has to teach. 2. The question is insulting to the teacher who has worked hard to put you in a position to appreciate the material—its intrinsic interest, its subtlety, its complexity. 3. Thus, the question “Will this be on the exam?” infuriates many instructors, and rightly so. ( from 1 and 2) 4. Therefore, you should not ask, nor be tempted to ask, the question: “Will this be on the exam?” (from 3) 2. 1. 2. 3. 4. 5. 6.

Science seeks to explain only objective knowledge, knowledge that can be acquired independently by different investigators if they follow a prescribed course of observation or experiment. Many human experiences and concerns[, including aesthetics and morality,] are not objective. Thus, many human experiences and concerns, including aesthetics and morality, do not fall within the realm of science. (from 1 and 2) Thus, science has nothing to say about aesthetics or morality. (from 3) [Aesthetics and ethics are essential to the functioning of human society.] Therefore, the functioning of human society clearly requires principles that stem from some source other than science. (from 4 and 5)

3. 1. Education is required in the performance of our most basic public responsibilities, even service in the armed forces. 2. It is the very foundation of good citizenship. 3. It is a principal instrument in awakening the child to cultural values, in preparing him for later professional training, and in helping him to adjust normally to his environment. 4. Thus, it is doubtful that any child may reasonably be expected to succeed in life if he is denied the opportunity of an education. (from 3) 5. Thus, today education is perhaps the most important function of state and local governments. (from 1, 2, and 4) 6. [All fundamental benefits and opportunities offered by the state must be made available to all on an equal basis.]


7. Therefore, a right to a public education is a right which must be made available to all on equal terms. (from 5 and 6) 4. 1. Everyone needs thinking skills to meet the demands of career and citizenship. 2. The highest of Abraham Maslow’s hierarchy of human needs, selfactualization, is unachievable without the ability to think productively. 3. [Maslow correctly identifies self-actualization as the highest human need.] 4. Thus, everyone needs thinking skills to realize his or her potential as a human being. (from 2 and 3) 5. Thus, to deny meaningful instruction in thinking to students below a certain IQ of proficiency level is to deny them an essential part of their humanity. (from 4) 6. The constitutional guarantees of freedom to speak, to choose one’s own religion, and so on, lose much of their meaning when only some individuals are trained to evaluate and choose among competing views. 7. Therefore, thinking instruction in elementary and secondary education should not be limited to the honors program. (from 1, 3, and 6) 5. 1.

2. 3. 4. 5. 6. 7. 8.

Providing all students in the twelfth grade with some kind of work-andstudy experience would help to overcome age segregation by allowing students to observe adults at work and, in doing so, to learn what it is like to work all day. It would give students the opportunity to overcome stereotypes about people who perform kinds of job different from their parents’. Students would see how education actually contributes to workaday life. Thus, the jobs would enhance the meaning of school work. (from 4) Young people would come to know better what they really like to do and what they are good at doing. Thus, they would develop clearer career aspirations. (from 5) Most important, the work experience could be used to make classroom discussions of social and economic institutions vivid and individually relevant. Therefore, consideration should be given to providing all students in the twelfth grade with some kind of work-and-study experience. (from 1-4, 6, 7)

6. 1. Teachers already have enough time during the school day to instruct children.


2. There are too many children that come home with either no adult there or no adult with the ability to help them with their homework. 3. This places many children at a disadvantage compared to other children who have their parents there to help them with their homework. 4. [Teachers should not give assignments that place some children at a disadvantage compared to others.] 5. Children, like adults, should have the luxury of being able to come home after a long day and have the rest of the day to themselves. 6. Therefore, teachers should assign no homework whatsoever. (from 1-5) 7. 1. All sorrow or pain is either something that is truly evil, or for something that is apparently evil, but good in reality. 2. There is something worse than pain or sorrow for that which is truly evil, namely, either not to reckon as evil that which is truly evil, or not to reject it. 3. Thus, pain or sorrow for that which is truly evil cannot be the greatest evil. (from 2) 4. There is something worse than sorrow or pain for that which is apparently evil, but really good, namely, to be altogether separated from that which is truly good. 5. Thus, pain or sorrow for what is apparently evil, but good in reality, cannot be the greatest evil. (from 4) 6. Therefore, it is impossible for sorrow or pain to be man’s greatest evil. (from 1, 3, and 5) 8. 1. Urban, southern, and western school districts have disproportionately low spending and high numbers of disadvantaged students. 2. Students in these areas constitute a growing proportion of U.S. students, and future productivity will depend on learning how to provide better education for them. 3. Recent research suggests that the achievement scores of minority and disadvantaged students respond to additional well-targeted educational expenditures and that significant score gains could occur. 4. Research also suggests that additional educational investment might be recouped through lower future social expenditures and improved economic productivity. 5. Such policies would reduce the achievement gap between racial or ethnic and income groups—a source of continuing social and political divisions and economic costs in society. 6. Improving the United States’ international standing requires lifting the scores of these students.


7. Therefore, urban, southern, and western school districts should receive the focus of educational policy attention. (from 1-6) 9. 1. A mail voting system requires so little time and effort on the part of voters that it makes it easy to forget the value of voting. 2. A mail voting system allows voters who cast their ballots near the end of the designated voting period to have a greater volume of information and perhaps more accurate information than other voters do. 3. There is a serious potential for voter fraud in elections conducted by mail. 4. In a mail voting system, some ballots may get lost in the mail or arrive late. 5. Therefore, we should not rush to adopt a mail voting system. (from 1-4) 10. 1. The economic cost of legal drugs is two-and-a-half times greater than that of illicit drugs. 2. [Thus, although legalizing drugs may take the profit motive away from the street and clandestine manufacturers, these drugs will continue to be manufactured and the economic costs of drugs will still be high. (from 1)] 3. Drug use not only impacts on the user, but has serious implications for families, community, consumers and others. 4. Legalizing drugs would open the floodgates of access to these moodaltering chemicals and would send a message that drugs are not harmful. 5. Thus, legalizing drugs would increase that risk that pilots, surgeons, and school bus drivers would use drugs on the job. (from 4) 6. Thus, drug use is not a right and should never be. (from 3 and 5) 7. [It is ridiculous to say that child abuse laws should be repealed because abuse of children is escalating.] 8. Saying drugs should be legalized because drug use is escalating is like saying child abuse laws should be repealed because abuse of children is escalating. 9. [Thus, it is ridiculous to say that drugs should be legalized because drug use is escalating. (from 7-8)} 10. Common sense and state experiments with the decriminalization of marijuana in the 1970s tell use that when there are fewer controls, there will be more incidents. 11. America’s two favorite legal drugs—alcohol and nicotine—have a tremendous negative impact on the physiological, social, psychological, economic and spiritual aspects of our lives. 12. Thus, if drugs were legalized, hospitalizations, crimes, car accidents, addicted babies, industrial accidents, family break-ups, and other problems afflicting our society would worsen significantly. (from 10-11) 13. [Therefore, drugs should not be legalized. (from 2, 6, 9, and 12)]


11. 1. There is no fair and objective way to measure effort in one’s academic work. 2. So, if professors based their grades on their perception of how much effort their students have expended, the grades would be wildly unfair and the professors would have to barricade themselves in their offices to ward off all the pleaders and complainers. (from 1) 3. If professors gave out grades based on effort rather than on achievement, students would be unable to assess their own learning. 4. If professors gave out grades based on effort rather than on achievement, outside evaluators such as employers and graduate schools would not know which students are likely to be top performers. 5. It is absolutely crucial to our nation’s health and prosperity that outside evaluators be able to know which students are likely to be top performers. 6. Therefore, professors should base their grades primarily on achievement rather than on effort. (from 2, 3-5)

Chapter 8: Evaluating Arguments and Truth Claims Exercise 8.1 This exercise invariably generates good class discussions. Of course, many of the points students make to support their beliefs are quite flimsy. A gentle Socratic approach works best. Exercise 8.2 I. This exercise requires a little planning. It works best if you ask a student confederate to take notes on how you looked the last time the class met--or, better still, show them a video or photo of how you looked. If you don't usually end class early, or carry a briefcase or backpack, you might wish to do so to enhance the effect. II. 1. Not reasonable (It is, or should be, common knowledge that tigers are native to Asia. Of course, some tigers do live in zoos in Africa.) 2. Reasonable (This, by now, is common knowledge.)


3. Not reasonable (This is a mere superstition.) 4. Not reasonable (The figure is too specific, and the claim is implausible on its face.) 5. Not reasonable (This is standard advertising puffery.) 6. Reasonable (credible source.) 7. Not reasonable (World War II ended more than 65 years ago.) 8. Not reasonable (The source is clearly biased, and the claim is inconsistent with credible expert opinion.) 9. This claim is true, but even people who know a great deal about U.S. geography are often surprised to hear it. Given background knowledge most of us share, it may not be reasonable to accept the claim based simply on the say-so of a stranger on the bus. 10. Reasonable (credible source) 11. Not reasonable (biased and unqualified source) 12. Not reasonable (Maybe a speed-reader could pull this off, but the claim is so intrinsically implausible that it's more reasonable to believe the person is pulling your leg.) 13. Not reasonable (The claim is inherently implausible given background knowledge most of us share, and Falwell was presumably not an expert on hate crimes.) 14. Arguable, but the claim seems implausible given background knowledge most of us share, and anti-gun control Web sites are not known for their objectivity and strict fidelity to truth. 15. No commentary necessary.

Exercise 8.3 I. 1. The statement is self-refuting. If not statements are true, then the statement that no statements are true isn’t true either. So if the statement is true, it’s false, which is a contradictory.


2. The statement is self-refuting. The statement “All generalization are false” is itself a generalization, and hence false in its own terms. 3. Since, by definition, brothers are males and nieces are females, the statement is necessarily false (assuming that, necessarily, no males are females). 4. The statement is self-refuting. If no beliefs are justified, then the belief that no beliefs are justified isn’t justified either. So fit he statement is true, it’s false, which is contradictory. Looked at another way, if we should be absolute and total skeptics (i.e., hold that no beliefs are justified), we should be skeptical of the claim that we should be absolute and total skeptics, and hence not be absolute and total skeptics. The statement asserts that we should be absolute and total skeptics, yet implies that we shouldn’t, which is contradictory. 5. To say that an object is “red all over” is to say that its entire surface is red with no admixture of another color. Hence, it is self-contradictory to assert that an object is red all over and blue all over (at the same time. 6. Since kissing, as standardly understood, requires lips, and disembodied spirits have no lips, it is impossible to be kissed by a disembodied spirit. 7. If the claim is that all children in Lake Wobegone are above average with respect to other Lake Wobegone children, the claim is necessarily false, for something can be above average in a comparison group only if some other things in the group are below average. The statement is not necessarily false if it means that all children in Lake Wobegone are above the national average. 8. Notice that it is not stated that Joseph killed his grandfather when his grandfather was a child (or before his grandfather was able to beget children). If it did, the statement would be necessarily false, because then Joseph would never have been born. The deeper problem is with the very concept of time travel. Many philosophers argue that it is logically impossible to travel to the past, for this implies that something both happened and did not happen at a particular time in history. It might be said, in reply, that travel to the past creates a new “time line,” with two distinct but logically compatible historical sequences running parallel to each other. It isn’t clear that this notion of distinct time lines is coherent. But even if it is, this wouldn’t involve travel to the past, because the modified historical sequence has never occurred before, and is therefore not in the past. II. 1. What about polar bears, seals, walruses, and orcas, to name a few? 2. Keeping promises is important, but other things, such as saving lives, may sometimes be more important.


3. What about if an urgent message is expected, e.g., regarding the birth of a child or a medical emergency? 4. Plausible counterexamples include: Thoreau, Melville, Hawthorne, Poe, Fitzgerald, Hemingway, and Faulkner, among others. 5. What about bananas, pears, limes, lemons, blueberries, kiwis, grapes, peaches, cantaloupes, etc.? 6. In countries such as Guatemala, Iran, and Indonesia, the United States has supported, and in some cases installed, corrupt authoritarian governments. 7. Don’t forget good ol’ Ohio and Utah. III. 1. Answers will vary for these exercises. Pertinent counterpoints to this argument include: Not all colleges cost a fortune. Often students who were bored in high school find that they enjoy college work. Though jobs like trucking and construction may be relatively high-paying, the work may be more dangerous, less enjoyable, less prestigious, and less secure than many jobs that require a college education. The difference in earning power may also be greater than this individual supposes. Studies show that college graduates make on average about 45% more than those who have only a high school diploma. 2. Pertinent counterpoints: Average life expectancy for U.S. residents has increased from age 60 in 1930 to over age 77 today. Moreover, a 65-year-old American today has a 50% chance of living to 82, and a 25% chance of living to 92. Thus, there is a good possibility this person will need some retirement savings—and not just to pay for a nursing home. Saving for retirement—particularly with widely available employer matching funds—need not cost an arm and a leg. A 22-year-old who saved just $75 a week would have nearly $1.5 million in savings by age 65 (assuming an 8% average annual rate of return). And of course in most cases unused retirement income can be passed on to one’s heirs. 3. Pertinent counterpoints: Gender discrimination may often take subtler forms today, but there is ample evidence it still exists, both on a personal level and in the way workforce norms are structured. Also, posing this simply as an issue of “personal choice” ignore the reality of powerful societal pressures and expectations that influence and often limit women’s career choices. 4. Pertinent counterpoints: Although the meaning of the Second Amendment is hotly debated, few would argue that the “right to bear arms” extends to military-style weapons that are neither necessary for personal protection nor suitable for hunting.


Moreover, the risks of legalizing such weapons would seem to outweigh the gains. The threat of foreign invasion or a breakdown of society are probably pretty remote. By contrast, the risk that such weapons could fall into the hands of criminals or be used in Columbine-type massacres, domestic disputes, and accidental shootings is high. 5. Pertinent counterpoints: Tanning booths, like natural sunlight, emit ultraviolet radiation that causes skin cancer and wrinkling. Studies show that rates of skin cancer among women under 40 have tripled since the late 1970s, and that women who go to tanning salons more than once a month are more than twice as likely to develop skin cancer. 6. Pertinent counterpoints: Over 500,000 persons become naturalized U.S. citizens each year. What would the economic cost be of requiring all “able-bodied” applicants (of unspecified ages) to serve three years in the armed forces? How motivated would these “volunteers” be? What percentage would be women? Would it deter skilled or highly educated workers or students from coming to the U.S.? 7. Pertinent points that weaken or refute the argument include: The likelihood that legalizing hard drugs would lead to greatly increased use and addiction rates, with all the personal and societal costs this would entail: more overdoses, hospitalizations, car accidents, industrial accidents, suicides, family break-ups, unemployable workers, lower productivity, and so forth. Legalizing hard drugs would also likely make these drugs more readily available to children and implicitly send a message that these drugs aren’t all that harmful. 8. Pertinent counterpoints: Obviously, there may be significant upsides to marrying career women, even assuming these research findings are sound. For many men, marrying a “career woman” (however that is defined) may greatly increase their standard of living and result in a happier, more simpatico marriage. It is relevant to ask, too, what would happen if all men thought like this individual. Few women—or men, we feel sure—would be happy returning to the kind of “Father Knows Best” world that would result. 9. Read the papers lately? IV. Here are one reader's standardizations of these essays. Stan Daniels, Helmet Laws Discriminate against Bikers 1. There is no discernible difference in motorcycle injury or fatality rates between states that have mandatory helmet laws and those that don't. 2. Motorcycles represent just 2 percent of total vehicles in the United States and account for less than 1 percent of all vehicle accidents.


3. Thus helmet laws are unnecessary. (from 1-2) 4. [If golfers are not required to wear helmets and hunters are not required to wear bulletproof vests, then helmet laws are discriminatory.] 5. Golfers are not required to wear helmets and hunters are not required to wear bulletproof vests. 6. Thus, helmet laws are discriminatory. (from 4-5) 7. Helmets are annoying to motorcycle riders who don't wish to wear them. 8. Helmet laws have no effect on anyone except motorcycle riders. 9. In a free society, responsible citizens should be allowed to choose what safety measures best suit their particular needs. 10. In a recent local television poll, 82 percent of callers favored repealing Pennsylvania's mandatory helmet law. 11. Therefore, helmet laws should be repealed. (from 3, 6, 7-10) Leonard Pitts, Don't Use God's Law to Beat Up on Gays 1.God is mercy and love. 2. If I was given a heart and mind, God must have wanted me to use them. 3. The Bible says men ought not to judge. 4. When the scribes and Pharisees brought before Jesus a woman caught in the act of adultery and demanded that she be stoned in accordance with God's law, Jesus faced them and said the one who was without sin should cast the first stone. 5. Many passages in the Bible--for example, Leviticus 20:9 (mandating death for cursing your parents), Leviticus 20:10 (mandating death for committing adultery), I Corinthians 11:14 (condemning men who wear long hair), and I Corinthians 11:34-35 (condemning women who speak out in church)--are not, and should not, be interpreted as still-binding divine law. 6. [Therefore, don't use God's law to beat up on gays. (from 1-5)] Constance Hilliard, We're Spendthrift "Environmentalists"


1. Although eight out of 10 Americans regard themselves as environmentalists, Americans comprise a mere 5 percent of the world's population and consume an estimated 30 percent of its non-replenishable resources. 2. This unbridled consumerism is, as Roger Rosenblatt notes, "threatening the ecological balance of our entire globe." 3. We suffer more stress-related illnesses now than ever before, while neglecting family and intimate relationships in our time-consuming struggle to surpass the Joneses. 4. Our patterns of overconsumption reflect a dependency, a need for constantly whispering promises of untold bliss that mere goods simply cannot keep. 5. Thus, the more single-mindedly we grab for the elusive, nirvana-like American Dream, the more inexorable the slippage in our quality of life. (from 3-4) 6. Therefore, in this holiday season of frenzied shop-'til-you-drop spending, those of us who call ourselves environmentalists should take time out to re-evaluate our personal patterns of consumption. (from 1-2, 5) USA Today, “Campus Rules Overreach” 1. Speech codes at [public] colleges that squelch all but the most bland and conformist comments violate students’ constitutional rights to free expression. 2. A free exchange of ideas is supposed to be an integral part of the college experience. 3.

Encouraging students to show sensitivity is laudable, but it’s better achieved through persuasion than coercion of those who express disagreeable views.

4. According to the head of the U.S. Department of Education’s Office of Civil Rights, federal rules that ban sexual or racial harassment are intended to protect students from discrimination, not regulate speech. 5.

[Federal courts would agree with this official’s interpretation of the law.]


[Thus, restrictive speech codes are not needed to comply with federal rules that ban sexual or racial harassment. (from 4 and 5)]

7. Therefore, colleges should not seek to promote campus harmony by means of restrictive speech codes. (from 1-3, 6) Richard Delgado, “Hate Cannot Be Tolerated” 1. Federal courts have extended “hostile environment” case laws to schools that tolerate


a climate of hate for women and students of color. 2. [Thus, colleges may need to enact reasonable campus hate-speech codes to avoid being sued for sexual or racial harassment. (from 1)] 3. In many cases, the usual and preferred response to hate speech—“more speech”—is either unavailable or too dangerous for the victim. 4. College counselors report that colleges where highly publicized incidents of hate speech have taken place see a decline in minority enrollment. 5. [Declines in minority enrollment are undesirable for colleges.] 6. Society is becoming more diverse. 7. Courts, rightly, have struck down overly broad campus speech codes, but they are likely to uphold reasonable, narrowly crafted rules that accommodate diversity and hone in on the most offensive forms of speech. 8. Therefore, reasonable, narrowly crafted college hate-speech codes are to be applauded, not feared. (from 2-7)

Sean Curtis, Why Cats Make Better Pets Than Dogs 1. Unlike dogs, cats need to be fed only once a day or once every few days. 2. Unlike dogs, cats don’t need to be taken for walks on sub-zero mornings. 3. Unlike dogs, cats poop in one place. 4. So, dogs are higher maintenance than cats. (from 1-3) 5. Unlike dogs, cats don’t bark. 6. Unlike dogs, cats don’t jump on house guests and get their smell all over them. 7.

[So, cats are less annoying than dogs.] (from 5-6)


Cats can be just as loving as dogs.

9. Therefore, cats make better pets than dogs. (from 4,7, and 8)


John Tierney, On Campus a Good Man Is Hard to Find 1. Affirmative action policies for boys in public colleges aren’t fair to the girls who are rejected despite having higher grades and test scores than many of the boys who are admitted. 2. Such policies aren’t fair to the boys if they’re not ready to keep up with their classmates. 3. Government shouldn’t favor one group over another. 4. Fewer boys than girls go to college, not because of any discrimination boys have faced, but because boys are less fond of school than girls are and are more inclined to skip college in favor of relatively well-paying jobs in fields like construction and manufacturing. 5. [Thus, affirmative action for boys in public colleges cannot be justified as a remedy for past discrimination. (from 4)] 6. Therefore, public colleges should not practice affirmative action for boys. (from 1-3, 5) USA Today, Don’t Blame the Burgers 1. Nine of 10 Americans say it’s wrong to hold food companies liable for obesity-related health problems. 2. People who know or should know that eating copious orders of high-calorie fast foods is unhealthy and may result in weight gain have only themselves to blame. 3. Advice to avoid such foods is hard to miss. 4. [Thus, it cannot plausibly be claimed that fast-food chains have deceived customers about their products. (from 3)] 5. It’s a stretch to suggest that McNuggets are as addictive or dangerous as nicotine. 6. [Thus, “fat” lawsuits, in contrast to lawsuits against Big Tobacco, cannot be justified by claiming that the products sold are highly addictive or dangerous. (from 5)] 7. Ultimately, good eating habits are a matter of personal and parental responsibility. 8. Thus, it is not the place of the law to protect people who eat too much fast food from their own excesses. (from 1-2, 4, 6, 7) 9. Food companies are responding to health findings and consumer demand by, for


example, posting nutritional information and phasing our Super Size programs. 10. Market forces and public education will work better than lawsuits and government edicts in trimming the nation’s midsection. 11. Therefore, our nation’s obesity epidemic should not be addressed by “fat” lawsuits or government edicts, but by market forces, public education, and an emphasis on personal responsibility. (from 8-10) USA Today, End the Death Penalty; Use Life Without Parole 1. Studies show that the death penalty dooms the innocent along with the guilty. 2. Studies show that capital punishment has a “brutalizing effect” that actually seems to incite killers. 3. Studies show that the average murder rate in death-penalty states is substantially higher than the average murder rate in non-death-penalty states. 4. Thus, the death penalty actually makes our society more violent and our persons less secure. (from 1-3) 5. Studies show that the death penalty is applied in an arbitrary and racially discriminatory way. 6. [If the death penalty is applied in an arbitrary and racially discriminatory way, then it cannot be reconciled with the Constitution.] 7. Thus, the death penalty cannot be reconciled with the Constitution. (from 5-6) 8. The death penalty bogs down the courts. 9. The death penalty encourages legalistic manipulation. 10. Thus, the death penalty erodes the system’s integrity. (from 9) 11. Thus, the death penalty is a failure as a tool of law, justice or public safety. (from 4, 7-8, 10) 12. Life without parole means what it says: There is no parole. 13. Life without parole is indisputably constitutional. 14. Life without parole is cheaper than the death penalty. 15. Life without parole is easier to win than the death penalty.


16. Life without parole may actually deter crime better than the death penalty. 17. Thus, we should abolish the death penalty and use life without parole instead. (from 11-16)


Chapter 9: A Little Categorical Logic Exercise 9.1 1. No artichokes are fruits.

2. Some rectangles are squares.

3. All architects are professionals.

4. Some skateboarders are jazz fans.


5. Some tattoo artists are not archbishops.

6. All persons born in the United States are U.S. citizens.

7. No women are persons that have been U.S. presidents or vice-presidents.

8. Many dwarves are bachelors.


9. Not a single chess master is a rock star.

10. Some of the world's greatest soccer players are South Americans.

Exercise 9.2 1. All psychiatrists are doctors. 2. All persons that rush in are fools. 3. All blue jays are birds. 4. All Mustangs are Fords. 5. All persons that may use the restroom are employees (of this establishment). 6. All eligible for the honor society are persons with a 3.8 GPA or higher. 7. All players due to report on Monday are pitchers or catchers. 8. All persons allowed in the hall are persons with passes. 9. All persons eligible for the discount are senior citizens. 10. All persons that may use the Teacher's Lounge are teachers. 11. All friends of the devil are fires.


12. All sober dancers are lunatics. 13. All persons God loves are persons who dwelleth in wisdom. 14. All times when man is wholly human are times when he plays. 15. All persons I loathe are executioners. Exercise 9.3 I. 1. All maples are trees. 2. Some roses are red. 9. Some bats are nocturnal animals. 4. All insects are animals. 5. Some desserts are foods that are not fattening. 6. All igloos are structures made of ice. 7. Some things that glitter are not gold things. 8. No cheaters are persons that prosper. 9. All clouds are things that have silver linings. 10. All times when you hit the ball are times when you swing the bat. 11. All events that are identical with World War II are events that began in 1939. 12. All cars are vehicles. 13. Some birds are animals that cannot fly. 14. Some Wessex College students are students that graduate in four years. 15. Some sheep are not white sheep. 16. All places are places where the grass is greener on the other side.


17. Some persons are not humans. 18. No mammals are reptiles. 19. Some polar bears are animals that live in Canada. 20. All humans are persons who prefer belief to the exercise of judgment. 21. Some persons are persons that have been ruined by success. 22. All liars are thieves. 23. All free persons are educated persons. 24. All persons that go to a psychiatrist are persons that should have their heads examined. 25. Some persons are persons that live lives of quiet desperation. 26. No places are places more delightful to a person than that person's own home. 27. No things that are not worth doing are things that are worth doing well. 28. All persons that persevere in error are fools. 29. All lives that are worth living are examined lives. 30. All persons who say farewell when the road darkens are faithless persons. 31. All certainties are certainties that nothing is certain. 32. All (true) men are nonconformists. 33. All persons who have a why are persons who can bear with almost any how. 34. All villains dwelling in Denmark are arrant knaves. 35. Some men are rogues. II. Translation into standard-categorical form is the most difficult part of categorical logic for most students. This exercise provides additional practice.


Exercise 9.4 I. 1.

No barracuda are pets. No sharks are barracuda. So, no sharks are pets.


No farmers are city-dwellers. All city-dwellers are urbanites. So, no urbanites are farmers.


All curmudgeons are pessimists. All pessimists are cynics. So, some cynics are curmudgeons.



Some bankers are vegetarians. No anarchists are bankers. So, some anarchists are not vegetarians.


No beach bums are workaholics. Some beach bums are rollerbladers. So, some rollerbladers are not workaholics.


All violinists are musicians. Some bookworms are violinists. So, some bookworms are musicians.



No poker players are early-risers. Some firefighters are early-risers. So, some firefighters are not poker players.


Some millionaires are philanthropists. All philanthropists are altruists. So, some altruists are millionaires.


Some telemarketers are Methodists. Some Methodists are Democrats. So, some Democrats are telemarketers.



No Fords are Pontiacs. All Escorts are Fords. So, some Escorts are not Pontiacs.


No mockingbirds are cardinals. Some cardinals are songbirds. So, some songbirds are not mockingbirds.


All ecologists members are environmentalists. All ecologists members are wilderness lovers. So, all wilderness lovers are environmentalists.



No landlubbers are sailors. Some sailors are not pirates. So, some pirates are not landlubbers.


All cats are carnivores. All tigers are cats. So, all tigers are carnivores.


All sound arguments are valid arguments. Some sound arguments are mathematical arguments. So, some mathematical arguments are not valid arguments.



No fish are reptiles. All trout are fish. So, some trout are not reptiles.


Some idealists are not romantics. All idealists are dreamers. So, some dreamers are not romantics.


Some stockbrokers are couch potatoes. All stockbrokers are e-traders. So, some e-traders are couch potatoes.



Some butchers are not bakers. No butchers are candlestick makers. Therefore, some candlestick makers are not bakers.


All meteorologists are forecasters. Some forecasters are psychics. So, some psychics are meteorologists.


II. 1.

No Nobel Prize winners are rock stars. Some astrophysicists are Nobel Prize winners. So, some astrophysicists are not rock stars.


Some philosophers are determinists. All fatalists are determinists. So, some fatalists are philosophers.


All maples are trees. No bushes are trees.


So, no bushes are maples.


All liberals are big-spenders. All persons identical to Senator Crumley are big-spenders. So, all persons identical to Senator Crumley are liberals.


Some tarot-card readers are lottery players. All tarot-readers are frauds. So, some frauds are not lottery players.


All sonnets are poems. No mathematical treatises are poems. So, no mathematical treatises are sonnets.



Some lawyers are not golfers. All lawyers are persons who have attended law school. So, some persons who have attended law school are not golfers.


No cardsharks are psychics. All cardsharks are poker players. So, some poker players are not psychics.


No fish are mammals. All pickerel are fish. So, no pickerel are mammals.



All political scientists are social scientists. Some political scientists are persons who favor campaign finance reform. So, some persons who favor campaign finance reform are social scientists.


No egoists are humanitarians. No humanitarians are sweatshop owners. So, no sweatshop owners are egoists.


Some e-mail messages are not messages that are spell-checked. Some interoffice memos are e-mail messages. So, some interoffice memos are not messages that are spell-checked.



All tax-evaders are lawbreakers. No lawbreakers are model citizens. So, no model citizens are tax-evaders.


No trucks are cars. Some Mazdas are trucks. So, some Mazdas are not cars.


All dogs are furry animals. All animals identical to Lassie are dogs. So, all animals identical to Lassie are furry animals.



No harmless acts are immoral acts. Some lies are not harmless acts. So, some lies are not immoral acts.


All mystics are religious persons. Some religious persons are not greedy persons. So, some mystics are not greedy persons.


All persons who drink and drive are irresponsible persons. Some persons who talk on a car phone are not irresponsible persons. So, some persons who talk on a car phone are not persons who drink and drive.



All persons who eat pizza every night are persons at risk for heart disease. Some persons who are at risk for heart disease are cab drivers. So, some cab drivers are persons who eat pizza every night.


All persons identical to Joey are kindergarteners. All children who finger paint in school are persons who are kindergarteners. So, all persons identical to Joey are children who finger paint in school.


Chapter 10: A Little Propositional Logic Exercise 10.1 I. 1. p 2. p & q 3. p & q 4. p & q 5. p & q 6. p & q 7. p & q 8. p & q 9. p & q 10. p & q II. 1. T 2. F 3. F 4. T 5. F 6. T 7. F 8. F 9. T 10. F III. 1. T 2. F 3. F 4. T 5. F 6. F 7. F 8. T 9. F 10. T


Exercise 10.2 I. 1.






II. 1. p q ... p & q


2. p .. p & q .

3. p .. q .

Exercise 10.3 I. 1. F 2. T 3. T 4. F 5. F 6. T 7. F 8. F 9. T 10. T


II. Students find this exercise helpful. It makes clear to them that the symbols and variables are meant to stand for thoughts and statements. III. 1. p & ~q 2. ~p & ~q 3. ~ (p & q) 4. ~p & q 5. ~ (p & q) 6. ~p & ~q 7. p & ~q 8. ~ (p & q) 9. ~p & q 10. ~ (p & q) IV. 1.








1. ~p & ~q ... ~ (p & q)

2. ~(p & q) ... ~ q

3. ~(p & q) ~p ... ~q



~ (p & q) p . . . ~q

5. ~ (p & q) ... ~p & ~ q

Exercise 10.4 I. 1. T 2. F 3. F 4. F 5. T 6. F 7. T 8. T 9. F 10. T


II. Students find this exercise helpful. It makes clear to them that the symbols and variables are meant to stand for thoughts and statements. III. 1. (c & d) & ~k 2. c & d & h 3. ~(c & d & h) 4. (t & b) & ~ w 5. ~((t & b) & ~w) IV. 1.







V. 1. f&t ~s ... ~(f & s)

2. f&p ~r . . . ~(p & r)


3. ~ (f & b) ~g ... ~ f & ~ g

4. s & ~e ~(e & t) ... s & t


5. ~(f & j) ~c ... ~j & ~c

Exercise 10.5 I. 1. T 2. T 3. F 4. T 5. T 6. T 7. T 8. T 9. T 10. F II. Students find this exercise helpful. It makes clear to them that the symbols and variables are meant to stand for thoughts and statements. III. 1. d v r 2. (d v r) & ~s 3. ~ (d v r) 4. w v d 5. w v ~d 6. (w v ~ d) & ~ g


7. p v f 8. ~(e v c) 9. (s v a) & ~ (s & a) 10. ~ (t v a) & w IV. 1.


(Because the premises are inconsistent there are no cases in which the premises are both true and hence no cases in which the premises are both true and the conclusion is false. Because this example requires some explanation it may be better suited for the classroom than for homework.)






V. 1. dvr ~r ... d

2. (d v r) & ~s ... ~(s v d)


3. ~ (e v c) c ... ~e

(Because the premises are inconsistent there are no cases in which the premises are both true and hence no cases in which the premises are both true and the conclusion is false. Because this example requires some explanation it may be better suited for the classroom than for homework.) 4. sva ~ (s & a) a ... s


5. ~ (t v a) avw ... ~t

Exercise 10.6 I. 1. F 2. T 3. F 4. T 5. T 6. T 7. F 8. T 9. T 10. T II. Students find this exercise helpful. It makes clear to them that the symbols and variables are meant to stand for thoughts and statements. III. 1. b  e 2. ~(h  t) 3. ~b  ~e 4. h  f 5. ~b  ~h 6. e  c 7. ~c  ~e


8. ~g  ~s 9. ~(~g  ~s) 10. (s  g)  (~s  p) IV. 1.


(There are no cases in which the premises are both true and hence no cases in which the premises are both true and the conclusion is false. Because this example requires some explanation it may be better suited for the classroom than for homework.) 3.





V. 1. be ~e ... ~b

2. ~b  ~h b ... h

3. ec ~e ... ~c


4. gs . . ~g  ~ s .

5. sg g&t ... s


Chapter 11: Inductive Reasoning Exercise 11.1 1. Strong. 2. Weak. 3. Weak. 4. Strong. 5. Weak. 6. Weak. 7. Strong. 8. Strong. 9. Strong. 10. Weak. Exercise 11.2 I. 1. Strong. Is the sample large enough? Yes. Is the sample representative? Yes. 2. Strong. Is the sample large enough? Yes, probably. Is the sample representative? Yes, probably. 3. Weak. Is the sample large enough? Yes. Is the sample representative? No, women are excluded. 4. Weak. Is the sample large enough? Yes. Is the sample representative? No, a far higher percentage of Americans attend college than is typical in other countries. 5. Weak. Is the sample large enough? Yes. Is the sample representative? Possibly not. II. 1. Is the sample large enough? No, just three cities are considered. Is the sample representative? No, not necessarily; for example, at least two of the cities have problems with illegal immigration which may add to the crime problem. 2. Is the sample large enough? Yes. Is the sample representative? No, not necessarily, since people may live considerably longer in the future. 3. Is the sample large enough? Yes. Is the sample representative? No, all the frogs are from one pond in a precarious location. 4. Is the sample large enough? Possibly, depending on the size of the faculty. Is the sample representative? No, they are all from one department; other departments may grant tenure to far fewer applicants..


5. Is the sample large enough? No, one hundred people is not enough to support this conclusion. Is the sample representative? No, definitely not. They are all children. Teenagers and adults may evaluate the movie differently.

Exercise 11.3 This exercise works particularly well with cooperative learning strategies. Try assigning students to groups either in class or for homework, and have them present their plans for the poll. Exercise 11.4 I. 1. c) Strong and reliable. 2. b) Strong but unreliable. 3. a) Weak. 4. c) Strong and reliable. 5. a) Weak. 6. b) Strong but unreliable. 7. c) Strong and reliable. 8. a) Weak. 9. a) Weak. 10. c) Strong and reliable. II. Students find this exercise helpful. Constructing their own arguments to fit the specifications gives them a deeper understanding of the concepts involved. Exercise 11.5 This exercise provides a good opportunity for students to test their “logical instincts.” Discussing their answers will help clarify the main issues involved. Exercise 11.6 1. 2 The skills involved are very different. 2. 2 There are too many dissimilarities and life doesn’t really have well-defined rules the way chess does. 3. 6 There are a too many dissimilarities.


4. 5 There are big differences between a small family budget and a large city budget. 5. 9 Changing the oil in a car is a pretty straightforward procedure and a transferable skill, especially considering that Fords and Chevys are both American made cars. 6. 3 Changing a car’s oil is far less complicated than changing its brakes. Also Chevys and BMWs are very different kinds of cars. 7. 7 The argument does not claim very much, and considering Rodriguez’s’s athletic ability, love for the game, and practice, it isn’t unreasonable to claim that he could learn to play fairly well. 8. 9 The argument draws on some important similarities and modestly claims that its conclusion is “probably” true. 9. 5 The conclusion may be true but there are important dissimilarities between cars and colleges. 10. 3 The conclusion is too strong in claiming that he must be "just like" the character. There are a couple of important similarities but not enough to fully support the conclusion. Exercise 11.7 1. Obviously, the topic of abortion is controversial, and many students have a difficult time being objective about the argument from analogy. 2. This exercise works best as a homework assignment. Few students can “think on their feet” well enough to construct a good analogy on the spot. 3. For the same reason as above, this exercise works best as a homework assignment. Exercise 11.8 I. 1. Strong, but students will want to argue it is weak. 2. Weak. There are significant differences between animals and human beings. To strengthen the argument we would need to add evidence that human beings do not have to eat meat to survive whereas some animals do. We might also add a premise about the fact that human beings can think rationally and decide on what to eat in a way that animals cannot. 3. Strong. 4. Weak. In this case there is not much that could be added to strengthen the argument.


II. 1. A. B. C. D.

Strengthen. Strengthen. Weaken. Strengthen.

2. A. B. C. D.

Strengthen. Weaken. Strengthen. Strengthen.

3. A. Weaken. B. Strengthen. C. Weaken. D. Strengthen. 4. A. B. C. D.

Strengthen. Weaken. Weaken. Strengthen.

5. A. B. C. D.

Strengthen. Weaken. Weaken. Strengthen.


Exercise 11.9 1. Bob is a good employer because he knows the concerns of his employees and treats them fairly, runs a profitable business, and knows when and how to delegate authority. 2. The mayor of a small town must similarly know the concerns of his constituents, respond to them fairly, keep an eye on the bottom line, and know when and how to delegate authority. 3. So, Bob would be a good mayor of his small town. Strong, though not a perfect argument. 2. 1. Mr. Sanders is a good football coach because he knows the game and inspires his players. 2. Good teachers know their subject matter and inspire their students. 3. So, Mr. Sanders would be a good health teacher. Weak. Mr. Sanders may or may not know the subject matter necessary for teaching a health class. Coaches and teachers inspire students in related yet different ways. The skills involved in communicating as a teacher and as a coach are related but different. 3. 1. Jezebel lives a life based on lies and deceit, cheating on her husband and pretending to be someone she is not. 2. A good actress must pretend she is someone is not. 3. So, Jezebel would be a good actress. Weak. There are two many dissimilarities. Deceiving others and yourself about who you are and what you are doing is qualitatively different from assuming the role of another on stage or screen. 4. 1. Brad Pitt is a good actor, commanding attention on screen and often making passionate socially conscious films. 2. The president must command attention and have a passionate social conscience. 3. So, Brad Pitt would be a good president. Weak. Needless to say, the analogy is strained. The similarities are trivial and slight, while there are innumerable relevant dissimilarities.


5. 1. Sam was a bad Marine, taking advantage of his authority, showing little care or concern for others, shrinking from conflict, and exercising bad judgment. 2. A good police officer must not abuse his authority, care for others, rise to the situation in conflict, and exercise good judgment. 3. So, Sam will be a bad police officer. Strong, though not a perfect argument. Exercise 11.10 I. 1. Bad evidence. Being old does not cause one to be uncomfortable with computers, but there is a correlation between being old and being uncomfortable with computers. 2. Good evidence. 3. Bad evidence. Being Caucasian does not cause one to have skill in playing hockey. There is, however, a correlation tied to socioeconomic factors. 4. Good evidence that studying causes higher grades. 5. Bad evidence. It is not the absence of nicotine ingestion that causes weight gain. Rather there is a correlation between increased caloric intake and smoke cessation. 6. Bad evidence for a causal relationship. Likely explained as a correlation between political affiliation and beliefs regarding the bill. 7. Good evidence for a causal relationship between a combination of decreased caloric intake and increased exercise resulting in weight loss. 8. Good evidence that the conditions they endured on the camping trip caused them to catch a cold. 9. Bad evidence. Being tall does not cause a person to play basketball; nor does playing basketball cause a person to grow tall. 10. Good but not perfect evidence. II. 1. What else did he eat? Did anyone else become sick from eating it? 2. Does the launch disturb the atmosphere? Do they have nasty weather anywhere else? 3. What percentage of habitual tobacco chewers get mouth cancer? What is the percentage of mouth cancer in the general public? Do tobacco chewers tend to do anything else that might result in mouth cancer? 4. The percentage of women with breast implants who have connective tissue disease; the percentage of women in the general public who have connective tissue disease; the


percentage of women with silicon breast implants who have connective tissue disease; the percentage of women with saline breast implants who have connective tissue disease. 5. The actual percentage of vegetable juice drinkers who maintain good health; how often do they actually get sick; what other health promoting practices, habits, or activities are common to them; quantity of vegetable juice they drink daily. 6. Need a definition of acts of violence; need actual percentages of children who watch professional wrestling and commit acts of violence versus those who do not watch professional wrestling. What else is characteristic of children who commit acts of violence? 7. Why do students choose to sit in the front row? 8. A decrease in high blood pressure of what percent is found when there is decrease in salt intake of what percent? Do people who decrease their salt intake in order to reduce high blood pressure do anything else that might result in a decrease in high blood pressure? 9. What is the percentage of cancer in communities with high dioxin content in their soil? What is the percentage of cancer in the general public? Is there anything else unusual about communities that have a high dioxin content in their soil? 10. How do we define a “healthy heart”? Just red wine, or other alcoholic beverages? Exercise 11.11 Note: These are tough. Students will say that some examples are ambiguous. Use this as an opportunity to discuss a context in which the example would not be ambiguous. Such discussion will help further clarify the different types of probability. 1. Relative frequency. 2. A priori. 3. Relative frequency. 4. Epistemic. 5. Epistemic. 6. A priori. 7. Epistemic. 9. Epistemic. 10. A priori. Exercise 11.12 I. 1. 2. 3. 4. 5.

Negative. Neutral. Positive. Negative. Negative.


II. This exercise is a good opportunity for discussion, which will reveal that not everyone places the same relative value on the same bets. III. This, too, is a good opportunity for discussion. Some students come up with good and relevant examples, which will clarify the concept for other students.


Chapter 12: Finding, Evaluating and Using Sources Exercise 12.1 The exercise can be very enjoyable. It works best if it is completed as described in the text—in groups of four or, if necessary, three. Encourage the group to record a consensus answer for each item. If the group cannot agree on an answer, the students should leave the item blank. After the students have completed their group discussions (which can take up to thirty minutes), spend some time discussing in general terms how individuals participate in group decisions and the dynamics you may have observed. When I do this exercise in class, I eavesdrop around the room and listen to how students debate the questions. After the discussions have ended I ask students to think about how they contributed to the discussion: Do they defer to others who seem more knowledgeable or more aggressive? How do they act when they know (or believe) they are right? Do they speak up to correct what they know is wrong? Did they go along with the majority decision? What did they do when they had only a vague notion they were right but no hard evidence? Did they trust their instincts? Were they easily swayed? Do they retreat to a “who cares?” or “whatever” position? And so forth. I don’t ask the students to announce their behavior to the class, just to think about their behavior in groups. Ask them to think about how the group decided on answers. Was it majority rule? Did they turn to the group’s “experts” on issues involving sports or religion or history? Did they guess at the answers or debate them? What evidence did they use to support their answers? Did they even ask for any evidence? If everyone seemed to be in agreement on a item, did anyone say, “Are we sure? Let’s discuss this.” How closely did they examine the items, especially in the true/false section? Did they take the statement apart, looking for one word that could make the statement false? (Because many students have taken true/false tests designed to trick them, students often do examine the language very carefully.) How often did the group simply guess? Finally, ask them to think about their intellectual curiosity. If I dismissed them at that moment, I ask, would they look up any of the answers? Would they ask me the answers on the way out or in the next class? (I don’t wait for an answer to those questions because I’m afraid to know. I only ask them to think about their curiosity, the lack of it, and the possible reasons for either.) Then move on the answers. The answer to most of the statements in Part I is an unqualified “false,” although many students will record “true” for all or almost all items. Explanations are provided below. Most of the answers students will give in Part II are predictable, but many of those answers will be incorrect or at least arguable. In some cases—in both Parts I and II, you should be ready for some debate, disagreement and downright incredulity among the students. They will also accuse you (and us) of splitting hairs, of being too strict, or of “tricking” them. It’s a good time to discuss precision and accuracy.


But, most important, the exercise shows that much of what we have often assumed to be true is not true. I make sure my students understand that the exercise is not intended to undermine their educations or demonstrate the weaknesses of their high school and elementary teachers, but that the exercise shows how we all believe things that may not be true. The purpose of the exercise is to encourage students to do research even into matters they feel are most obvious or conventional. In short, the aim of the exercise is to show students that they must be willing to “look it up.” In addition to Britannica Online, The following sources of information were used to create the true/false test: Adams, Cecil. The Straight Dope: Answers to the Questions that Torment Everyone! New York: Ballantine, 1984. Burnam, Tom. The Dictionary of Misinformation. New York: Harper, 1986. Cerf, Christopher and Victor Navasky. The Experts Speak: The Definitive Compendium of Authoritative Misinformation. Expanded and updated edition. New York: Villard, 1998. I. 1. Sort of. The Merrimac was a northern ship refitted by the South as an ironclad. The name was changed to the Virginia, so, strictly speaking, the first battle took place between the Virginia and the Monitor. 2. “Yankee Doodle” was most likely a British song that poked fun at the bumpkin colonists, who most likely coopted the tune. 3. “The Star Spangled Banner” was written during the War of 1812. The following is from the online version of Encyclopedia Britannica: Francis Scott Key, a lawyer, wrote the lyrics after watching the British attack Fort McHenry, Maryland, in 1814, during the War of 1812. The melody was taken from "To Anacreon in Heaven," a drinking song of the Anacreontic Society (of London) that was written by the British composer John Stafford Smith. Key's words were first published in a broadside in 1814 under the title "Defence of Fort M'Henry." The song's title was changed when it appeared in sheet-music form later the same year. After a century of general use, the four-stanza song was officially adopted as the national anthem by act of Congress in 1931. 4. Ferdinand Magellan died before the journey was completed. His first-mate, Juan Sebastian del Cano, finished the voyage and should be considered the first person to circumnavigate the globe.


5. Charles Lindbergh was the first person to fly solo across the Atlantic. 6. The Declaration of Independence was dated July 4, 1776, but signing did not take place that day. 7. Although students insist that this is true, many writers violate this “rule.” Some students will want to argue that, okay, then, it’s still true that you “should never” . . . . even though good writers do it. 8. The United States fought China in the Boxer Rebellion, in Korea, and indirectly in Vietnam. 9. While tenure protects the academic freedom of teachers, it does not protect them in cases of moral turpitude or financial exigency. 10. If a widower’s children are past age eighteen, he can join the priesthood. If a married Episcopalian priest converts to Catholicism, he can become a married Catholic priest. There are indeed married Catholic priests. 11. Victor Frankenstein, the scientist, never named his creature. 12. It began simply as an abbreviation. The Greek letter Chi (“X”) is short for Christ. 13. The Emancipation Proclamation (January 1, 1863) freed the slaves held in states “then in rebellion”; it specifically excepted states under the control of the Union army. Also, it proclaimed the slaves free, but it did not free them in the sense that they could walk away from their masters. (Students like to argue the “trickiness” of this question. I think these arguments are healthy and productive since students show their willingness to challenge the statement and me, and because it demonstrates the need to look very closely at language, sentence structure and history.) 14. Fulton built a steamboat, which was later named the Clermont, but it’s hard to argue that he “invented” it (you could discuss with your students the various definitions of “invent,” and for that matter “discover). Almost a quarter-century before Fulton’s ship sailed in the United States, a Frenchman, Marquis Claude de Jouffroy d’Abbans tested a model of a steamboat. In America, John Fitch should be credited for building the first functioning steamboat (1786). Fulton’s, however, was the first efficient and commercially successful steamboat 15. They were all hanged, not burned. One “warlock” was pressed to death with stones. 16. Franklin discovered that lightning was electrical and could be conducted by metal. Franklin is credited for inventing the lightening rod.


17. A common misconception is that the Immaculate Conception refers to Christ’s virgin birth. It refers instead to Mary’s having been conceived immaculately, in other words, untainted by original sin. Some students will show little concern for an item like this one. I sometimes use the occasion to ask whether there’s any value in knowing about religious doctrine and beliefs that may not be our own. 18. A old saying based on an old falsehood. II. 1. Although most of us associate them with Scotland and Ireland, bagpipes have been around for almost two thousand years in other parts of the world including western Asia. This question presents a good opportunity to discuss the meaning of words like “invent” and “discover” and to talk about how popular notions regarding the origin of inventions or ideas might need to be researched before we accept them as factual. Perhaps a student will volunteer to find out where bagpipes come from. And by the way, some purists insist that there are no “bagpipes”; it’s “bagpipe,” singular. 2. While some people believe that circumstantial evidence means evidence that is weak or unreliable, it is actually all evidence in a court case other than eyewitness testimony. All lab reports, fingerprint evidence, videotape, and so forth are circumstantial evidence, which is often the best evidence available. 3. In 1913, the major league baseball team from Brooklyn, New York, changed its name to the Dodgers after the custom of running quickly across the street to avoid oncoming trolley cars (trolley dodgers). The team moved to Los Angeles in 1958. 4. Many students educated in the United States will say Elias Howe. Some will say Isaac Merrit Singer. From Britannica Online: An early sewing machine was designed and manufactured by Barthélemy Thimonnier of France in 1841 to mass-produce uniforms for the French Army, but rioting tailors destroyed the machines. Thimonnier's design, in any event, merely mechanized the hand-sewing operation; a decisive improvement was embodied in a sewing machine built by Walter Hunt of New York City in about 1832-34 but never patented, and independently by Elias Howe of Spencer, Mass., and patented in 1846. In both machines a curved eye-pointed needle moved in an arc as it carried the thread through the fabric, on the other side of which it interlocked with a second thread carried by a shuttle running back and forth on a track. Howe's highly successful machine was widely copied, leading to extensive patent litigation and ultimately to a patent pool that included the design of Isaac Merrit Singer, the largest manufacturer. In 1860 more than 110,000 sewing machines were produced in the United States alone.


5. Although once a contraction for “mistress,” that usage no longer makes sense since, for example, Laura Bush is not Mistress Bush. As a title of courtesy for an unmarried woman, the term “Mrs.” is, strictly speaking, short for nothing. 6. Truman had no middle name, per se, and so the letter “S” is his “middle name.” His full name can be written Harry S. Truman or Harry S Truman (no period). 7. Many students will say that Ford invented the car; some will say the assembly line. He invented neither. 8. Almost everyone will say, with good reason, Thomas Edison. Here’s Britannica on the topic: In 1801 Sir Humphrey Davy demonstrated the incandescence of platinum strips heated in the open air by electricity; but the strips did not last long. Frederick de Moleyns of England was granted the first patent for an incandescent lamp in 1841; he used powdered charcoal heated between two platinum wires. The first practical incandescent lamps became possible after the invention of good vacuum pumps. The Englishman Sir Joseph Wilson Swan in 1878 and the American inventor Thomas Alva Edison in the following year independently produced lamps with carbon filaments in evacuated glass bulbs. Edison has received the major credit because of his development of the power lines and other equipment needed to establish the incandescent lamp in a practical lighting system. (See filament lamp.) The term “practical,” of course, changes everything. But it is interesting that even the first “practical” incandescent bulb is not credited to Edison alone. 9. Alexander Graham Bell will occur to most students. Britannica: The word telephone, from the Greek roots tele, "far," and phone, "sound," was applied as early as the late 17th century to the string telephone familiar to children and was later used to refer to the megaphone and the speaking tube; but in modern usage it refers solely to electrical devices derived from the inventions of Alexander Graham Bell and others. The U.S. patent granted to Bell in March 1876 (No. 174,465) for the development of a device to transmit speech sounds over electric wires is often said to be the most valuable ever issued. The general concepts involved in the invention of the telephone--of speech sounds as a complex of vibrations in air that is transferrable to solid bodies and of the convertibility of those vibrations to electrical impulses in conducting metals--had by then been understood for decades. Bell was but one of a number of workers racing to pull them together into a practical instrument for the transmission of speech.


What might a thorough research about Bell’s “invention” reveal? I use these previous two inventions—light bulb and telephone—to introduce a short discussion on how “facts” in our education are usually the result of where we are educated. Most students have no trouble admitting that an education in France or Sweden includes very different “facts.” 10. The Morse code distress signal, three dots followed by three dashes followed by three dots, corresponds to the letters SOS, but those letters were not intended to stand for anything. Many people believe, however, that SOS means “Save Our Ship,” or “Save Our Souls.” 11. The line is from Lincoln’s Gettysburg Address, but it is quoted inaccurately: “forefathers” is simply “fathers” in the address. 12. The fun in this item is in listening to students debate the issue. Students have argued that since Brazil is in the southern hemisphere, the sun must rise in the west. The answer is “east” in both cases, obviously, although Brazil has no west coast. The word “but” throws readers off, and some complain that the sentence is unfairly tricky. They are probably right, but this is a good time to talk about what happens when faced with “tricky” questions about what we know to be true. One final word of caution: Try to avoid at all costs giving the impression in this exercise that individual students or young people in general are unintelligent. I repeat several times during the hour that the exercise only points out how unreliable may be our conventional wisdom, memories, educations, and assumptions. The point again: be willing to look it up. Exercise 12.2 I. After students bring in their facts, I collect them and select forty or so facts, matters of facts and non-facts to share with the class. We discuss why an apparent fact cannot or should not be considered true. I also hand out a few opinions to show the difference between fact and non-fact. II. 1. Facts: Cal Thomas worked for NBC News in the late 1960’s. Robert Kitner was at one time president of NBC, as was Sylvester Weaver, who went by the name of “Pat.” Matters of fact: Stories were selected based on the audience they would attract (this could be verified with interviews, for example, or with corporate correspondence). Whether or not “ratings for news started to matter, as they did for entertainment” could be verified in similar ways, though some words, such as “mattered” would need to be clarified. The decline in the ratings could easily be documented. But what about the claim that “the respect most people once had for the journalism profession” also declined? Could that be documented through


surveys or opinions polls? Could such a statement be shown to be factual? 2. Book and movie reviews are a good source of writing that contains entwined facts and opinions, and, as one might expect, far more opinion than fact. These three reviews of The Dark Knight contain very little factual information and much critical commentary. Facts include: The film was made by Warner Bros, it was directed and co-written by Christopher Nolan, and it was Heath Ledger’s last performance. Students might want to argue whether the claim that The Dark Knight is the most anticipated movie of the year is a verifiable fact. 3. There are several claims presented as factual in Ward Churchill’s response to the question of whether the World Trade Center was an “acceptable” or legitimate target on Sept. 11, 2001. Students might be asked to research the following statements to determine whether or not they are true: 1) “[T]he C.I.A., the Defense Department, and other parts of the U.S. military intelligence infrastructure, had situated offices within” the World Trade Center. 2) “Saddam Hussein had situated elements of his command and control infrastructure within otherwise civilian occupied facilities.” 3) “The Donald Rumsfelds of the world, the Norman Schwartzkopfs, and the Colin Powells of the world”…”justified their bombing of civilian facilities [in Baghdad] in order to eliminate the parts of the command and control infrastructure that were situated there.” Therefore, “under U.S. rules,” Churchill argues, the World Trade Center was “an acceptable target.” Besides attempting to verify Churchill’s claims, students might also wish to examine his reasoning in the excerpted passage (does the passage illustrate the two-wrongs fallacy, or example? Does it contain a weak analogy?) Additionally, as an exercise in paraphrasing and summarizing, students might be encouraged to read Ward Churchill’s essay “People Push Back: On the Justice of Roosting Chickens,” a very difficult essay to paraphrase in absolutely neutral and objective terms. 4. Facts: Harvard is the oldest institution of higher learning in America; thirty-three Nobel prize winners graduated from Harvard; Bill Gates developed the programming language BASIC; Radcliffe was founded in 1879 and started admitting men in 1973; Martin Luther King Jr. received a doctorate in theology from Boston University, and so forth. Some statements, however, are not immediately verifiable. For example, it would be very difficult to document the claim that MIT is “generally acknowledged to be the nation’s top school for science and engineering.” The imprecise language—“generally acknowledged”—makes the statement more opinion than verifiable fact. Qualifying the statement might make it closer to being verifiable: “MIT is regarded among college presidents as the nation’s best school for engineering.” 5. Students might want to discuss, first, Coulter’s style, which is marked by a tendency to exaggerate the facts and needle her opponents. The imprecision and informality of her language in this excerpt make the job of pinning down facts nearly impossible. Nonetheless, her remarks provide an opportunity to discuss the sometimes subtle ways in which opinion is presented as fact. The following statements could be analyzed and


evaluated: “[T]he price of college tuition”…is not determined by “the quality of the product.” “CNN reports [in 2006] that college tuition has risen an astonishing 40 percent since 2000.” “[T]he solution [proposed by CNN?] is for the government to subsidize college professors’ salaries even more than it already does.” “Liberals think hardworking taxpayers who can’t afford gas should pay more in taxes.” Liberals think that “America is the worst country on Earth and that the American bond traders who were murdered on 9/11 deserved it.” Ward Churchill “makes $120,000 a year [2006] as a department head at the University of Colorado.” “The only part of his resume that has not already been proved false” is that he majored in communications and graphic arts. Exercise 12.3 1. Rush Limbaugh is a radio talk show host and author who espouses a conservative point of view. His claim that condoms fail “around’ seventeen percent of the time should be cautiously considered and verified with more reliable sources. One key to Limbaugh’s bias is his characterization of liberals in the first sentence of the quoted item. (Could he be charged here with a straw man fallacy?) 2. The author of this item from makes some effort to back up his or her evaluation with reasons, but the tone and generalizations suggest that the author’s purpose is retaliatory. Students might want to discuss the reliability of anonymous ratings sites such as Some students will suggest that a single evaluation has more credence if its comments are repeated in evaluations written by other students. (To start a good discussion, ask the students how useful or ethical a site called would be.) 3. Students seeking information on the author will discover that Dr. Robert A. Hatcher is Professor of Gynecology and Obstetrics at Emory University School of Medicine in Atlanta. His handbook on contraceptive technology is now in its 18th edition. Students might wish to discuss whether the evidence from 1998, quoted in the item, is still reliable but it is hard to deny that the source of this information is highly reliable. 4. The billboards proclaiming these “facts” are sponsored by someone who is attempting to reduce the level of immigration into the United States. The figures on the billboards may or may not be correct, but anyone hoping to use them in an argument would do well to corroborate the information with other sources. (A careful reader will notice the slippery language in less-than-reliable information. In the first billboard, how little is “very little”? In the second, “arrive” is a vague word with several possible meanings, including “visit.” 5. Pro-Life America’s numbers for condom failure are higher than Hatcher’s. The claim that the condom failure rate among teenagers is 36 percent is not verified except with vague reference to a “study.” Pro-Life America’s purpose here seems


to be to discourage sexual activity among teenagers, which may or may not call their numbers into questions. Students should be given an opportunity to discuss the possibility of bias and to research the numbers for themselves. Also, students might want to discuss what “failure rate” means. Pro-Life America seems to be suggesting that in every case, “condom failure” results in pregnancy. 6. Len Gougeon claims that Emerson and Thoreau were involved with the Underground Railroad and that both gave money to John Brown to buy rifles. Gougeon’s purpose seems to be to set the record straight. His language is straightforward, though “generously” is vague. Gougeon is a professor of literature whose letter is published in a very respectable magazine. Students might want to research how many letters to the editors of premier journals and newspapers (as compared to local dailies) are selected for publication. 7. It may well be true that 67 percent of listeners “would prefer that the races be separated.” But that doesn’t proved that “sixty-seven percent of people” prefer the same. Are the callers to a radio talk show a representative sample of “people” everywhere? Hardly. 8. Well, what did you expect him to say? 9. Students generally enjoy discussing the comic unreliability of tabloid newspapers such as The Weekly World News. They might be reminded that tabloids such as this cannot be trusted even when the news they print is true. It might also be noted that such tabloids are aimed at a gullible readership and that they have a disconcerting influence. Typing “planet-dissolving dust cloud” into Google will generate over 700 hits. 10. The Onion is an online parody newspaper that publishes satirical articles about newsworthy events (and non-events). Its intended audience—primarily regular readers who appreciate The Onion’s biting satire—won’t be misled by the passage. Given the patent implausibility of such an event, few others will be either. 11. Most students will understand immediately that the information in this item is coming from a partisan source. Students should be cautioned, however, not to dismiss the information out of hand (or to agree with it) until more research has been conducted to discover the truth about violent crime in America. Students might be encouraged to compare the Senate Democratic Policy Committee’s information to that provided by its Republican counterpart. See “Ten Key Facts on Key Issues,” 23 Oct. 2006, available at`rpc/index.cfm. 12. “Tracy” given no indication of a background in environmental science, though she (or he) makes several claims about the effectiveness of computer modeling in predicting climate change. How, students might ask, does Tracy know this? The harsh language she uses to describe her opponent calls her objectivity into


question. Students should be cautioned against making any generalizations about bloggers and might wish to discuss, instead, how and when to determine whether a blogger is a reliable source of information and opinion. How reliable, for that matter, is any information provided in personal spaces such as MySpace or Facebook? 13. America (The Book) is a satirical romp through American history written by Jon Stewart and the writers of Comedy Central’s fake new program, The Daily Show. The passage is obviously a joke, but a pointed one given longstanding debates about how disinterested the founding fathers’ motives were. 14. The U.S. Bureau of Labor Statistics is a very reliable source of information. This item presents a good opportunity to inform students about resources for reliable statistical information. 15. University Presses are generally reliable sources of information and opinion. Exercise 12.4 Answers will vary. The paraphrases below present only possibilities: 1. In her book, Starting Out Suburban: A Frosh Year Survival Guide, Linda Polland Puner suggests that most freshmen find it difficult to be away from home for the first time. They miss some of the comforts such as good meals and privacy. Some are lucky enough, particularly if their family lives nearby, to get home within the first month of school, but others must wait until Thanksgiving or even Christmas. Even just a semester away from home can seem very long and the distances can seem longer than they really are. 2. Two possible paraphrases: a) With his unique virtue and special skills, the cowboy, a distinctive American creation, is anointed by our culture as a mythic hero, Robert N. Bellah claims in Habits of the Heart: Individualism and Commitment in American Life. Though the cowboy is almost always seen as the outsider, it is a misconception to see him as antisocial. That special skill to defend towns and defeat villains, ironically, isolates the cowboy, as does his commitment to justice: though society needs and welcomes him, he is so special that he cannot be “one of us.” So, characteristically, the cowboy heroes “ride off into the sunset” or like the Lone Ranger are left with only one companion. b) America is also the inventor of that most mythic individual hero, the cowboy, who again and again saves a society he can never completely fit into. The cowboy has a special talent—he can shoot straighter and faster than other men—and a special sense of justice. But these characteristics make him so unique that he can never fully belong to society. His destiny is to defend society without really joining it. He rides off alone into the sunset like Shane, or like the Lone Ranger moves on accompanied only by his


Indian companion. But the cowboy’s importance is not that he is isolated or antisocial. Rather his significance lies in his unique, individual virtue and special skill and it is because of those qualities that society needs and welcomes him. 3. Two possible paraphrases: a) The photograph—to narrow it down—reduces us to two dimensions and it makes us small enough to be represented on a piece of paper or a frame of film. We have been trained by the camera to see the external world. We look at and not into, as one philosopher has put it. We do not allow ourselves to be drawn into what we see. We have been trained to go by the externals. The camera shows us only those, and it is we who do the rest. What we do this with is the imagination. What photographs have to show us is the external appearance of objects or beings in the real world, and this is only a portion of their reality. It is after all a convention. b) In Graven Images Saul Bellow contends that the convention of photography is to reduce the world to a small, two-dimensional image in which the viewer of the picture must supply the imagination to be able to see more than just the external representation. As such, the convention epitomizes our cultural training to look at rather than to be “drawn” into what we see. It is our imagination, though, Bellow suggests, that allows us the opportunity to see beyond the limitation of the external representation and discover a reality greater than the convention would appear to expose. 4. Researchers have found that phonemic awareness, or the ability to sound out words, is perhaps the single most important requirement for good reading skills. The ability appears to be a more important indicator of reading success than IQ scores and vocabulary and listening comprehension tests. Having a proper assessment tool in place, therefore, can help direct the teacher to awareness of potential problems and to the use of available exercises that will enable the student to acquire stronger spelling and reading skills. 5. A brief paraphrase: Hip-hop music and culture are becoming increasingly popular. Even young children are singing hip-hop lyrics, not knowing what they mean. Unfortunately, more and more messages of sexism and misogyny are taught through hip-hop lyrics and music videos. These messages force themselves into conventional thinking, leading to narrow-mindedness, heightened violence against women, increased rates of incarceration for minority youths, and the viewing of women as sex objects and fashion accessories. Exercise 12.5 1. Because rules are precise and must be followed to the letter, it would be best to quote the rule or the relevant part of the rule exactly as it appears in the book In claiming that a player should have lost a tournament, someone might write, “In hitting the ball twice, Sampras clearly violated Rule 20d, which prohibits the player from


‘deliberately touch[ing] it [the ball] with his racket more than once’ in a given point.” The writer would need, of course, to prove that the action was “deliberate.” 2. The comments in this excerpt could be paraphrased, although perhaps the last lien could be quoted: “This is the greatest generation any society has produced.” 3. The first line should be quoted (“Gym class was another brush with fascism”), but the rest of the passage could be paraphrased as long as the paraphrase didn’t lose the humor or tone. 4. The passage could be paraphrased or summarized with some phrases quoted if necessary. The following sentence might appear in a student’s paper: “Athletes who push themselves to the limit often incur injuries, but the medical community is now considering whether athletes who push too hard might be susceptible to “a host of chronic diseases, even cancer” (Tabor). 5. Students will want to quote most of this passage out of respect for the document and the writer, but much of the excerpt could be paraphrased while key phrases are retained. If you have time, ask your students to paraphrase this passage. Exercise 12.6 Many students know that ideas, opinions, interpretations, arguments and the like need to be documented. This exercise is intended to give students some practice in a more difficult aspect of research--determining when facts should be documented. Prepare to get some argument on many of these items. The arguments however can help demonstrate that with few exceptions (statistics, for example), knowing what to document is not an exact science, and that students need to think when deciding what to document. Many students, I’ve discovered, will want to document what they did not personally know, so that some students will, for example, want to document Barry Bonds' home run record. One handy device for helping in some cases is to ask students to imagine introducing the point with the phrase, “According to _______.” “According to The Sporting News, Barry Bonds holds the record for home runs in a season.” Such an introduction suggests that other sources would disagree, that the record is a matter of debate, or that only The Sporting News knows about the record. It should be clear that the fact does not have to be documented. On the other hand, some items seem to call for an introduction: “According to _________, Hitler applied to the Vienna Academy of Fine Arts in October 1907 but was rejected. Later, penniless and unwilling to work, he ended up in a homeless shelter.” The phrase “unwilling to work” might be debated among Hitler’s biographers. The item needs to be documented. 1. Fact available in wide variety of sources: does not need to be documented.


2. Could be considered common knowledge, but it might be best to tell where this fact was acquired. 3. Statistics always need documentation. 4. Although many people might be able to list from memory the five best-selling albums of all time, this fact should be documented. One clue that this information needs to be cited is the inclusion of a date, “as of August, 1999.” The fact may have changed since then, so it would be wise to say where the information came from. Also, it’s possible that different sources measure sales differently, another reason to document this item. 5. A fact surprising enough to be documented. 6. No need to document this, but a writer who did would not be violating any rules. 7. No need to document this fact; it is widely known and available. 8. Probably common knowledge. 9. Common knowledge. 10. This one is tricky. For scholars of Dickens’s life and work, this is a commonly known fact: Dickens’s childhood experiences are indeed reflected in several of his novels. Therefore, in preparing an argument for a literature class, a student would most likely find this information in several sources and would not have to cite it. However, a writer would not be incorrect in giving a source if he or she chose to do so. The paper might contain the sentence, “According to Charles Dickens’s friend and biographer, John Forster, the novelist’s childhood experiences, including his father’s imprisonment for debt and Dickens’s subsequent work in a shoe-polish factory, influenced his work as a novelist”. 11. This fact should be documented. 12. Because some students are confused by this fact, they will want to document it, although it does not need to be. 13. This is still being debated, so it would be best to tell the reader the source of the information. 14. Common knowledge, at least among baseball fans. No need to document. 15. Probably does not need to be documented any more that other scientific facts (the sun is approximately 93 million miles from the earth), but I would not quarrel with a student who provided the source of this information. Students should be reminded that they should check the accuracy of facts such as this one in other sources. If they find that the information is not common knowledge or is debatable, they should be ready to credit their sources.



Chapter 13: Writing Argumentative Essays This chapter walks students through the process of writing an argument, and each of the exercises reflects a step along the way. Exercise 13.1 At this point in the course, most students will understand that an argument is not a fight to be won at all costs and that they should defend their claims with well chosen evidence and clear logic. The opening of Chapter 13 provides an opportunity to remind students that while tactics such as overt emotional appeals, personal attacks and manufactured evidence might help “win” an argument, they have no place in serious arguments or discussions. Even if you decide not to include a written argument in the critical thinking course, this chapter may help students further realize the necessity of arguing fairly. Primarily, the opening part of the chapter asks students to keep in mind that all arguments should be evaluated on their merits and not on whether the audience agrees with them. Students should also know, however, that writing an argument is not a dry, bloodless exercise in marshalling evidence and premises to support a claim. This exercise gives you and students a chance to talk about the role of emotions in presenting an argument. Although this is, admittedly, a complicated topic, students might be asked, first, to recall how emotions can impede clear perception and rational thought. They might be asked to recall the fallacy that occurs when an arguer attempts to evoke irrelevant feelings in an audience. They might be asked further to decide when and how to use emotions in an argument. Obviously, a writer or speaker must have a great distaste for contradiction, illogic, unfair appeals and so on, and a love for clarity, precision, fairness, and so forth. Clearly the best arguments demonstrate a great passion for justice, a hatred of prejudice, and respect for opponents. But, students might be asked, can emotional appeals find their way into “good,” well-reasoned arguments? Is the appeal to emotions always fallacious? Students might be asked whether it is desirable, or even possible, to divorce “reason” from “feelings,” or to consider how an arguer might distinguish between his purely personal emotions and ones that are more widely shared and, perhaps, therefore more reasonable. Finally, this exercise ends the discussion of what makes an “good” argument and how arguments are to be evaluated. What follows from this point will help students construct arguments that will be evaluated according to prescribed criteria. (I sometimes ask my students if I should count my agreement and disagreement with a student’s argument as one of the criterion for assessment. They are unanimous in their decision.) I give the students the following assessment criteria when I assign the paper. Writer The writer avoids appearing to merely fulfill an assignment, and, instead, writes honestly, with confidence, conviction and enthusiasm, showing that he or she cares about the topic


and the claim. The writer demonstrates understanding of the topic chosen for discussion and does not defend the claim with unexamined, usually erroneous premises that are the result more of habit than thought or research. The writer avoids sounding arrogant, overly aggressive or pretentious and avoids egocentrism, sociocentrism or wishful thinking. The writer uses a tone appropriate to the topic. Audience The writer shows a keen sense of audience and does not insult, berate or ridicule readers or use personal attacks against those who hold an opposing view. The audience is assumed to be slightly skeptical, open-minded, intelligent, rational, humane and fair and is treated with respect. The writer anticipates reader’s reactions, especially those of potential opponents and renders opponent’s arguments accurately and charitably. Topic The selected topic is important, controversial (or unusual), interesting and narrow enough to be dealt with adequately in the space allowed. The writer avoids topics too complicated or too vast. Thesis The argument defends a single, central claim, usually expressed in a thesis statement provided in the opening paragraph. The thesis presents a position on the topic. The thesis is limited to the assertion that the writer intends to prove, and the essay does not digress from the thesis. Organization (Form) The essay contains an interesting introduction, body paragraphs that develop the thesis, and an effective conclusion. The essay flows coherently from paragraph to paragraph. A pattern of development is clear throughout the essay. The pattern is logical, effective and appropriate given the topic and the thesis. Opposing arguments are introduced and addressed at appropriate points in the essay. Development (Content) The central claim is defended with premises that are themselves, when necessary, supported with well-selected facts and opinions. Only credible sources are used. Premises and conclusions are connected logically. Fallacies and emotional appeals are avoided. Assumptions are examined. Key terms are defined when necessary, and definitions are provided in a suitable manner. Opposing arguments are rebutted convincingly. Arguments and subarguments are cogent or sound. The overall argument is complete.


Expression Sentences are clear, concise, and complete; the essay is free of grammatical errors. Sentence structures and lengths are varied to avoid a “choppy” style. Words are carefully selected and used correctly. Conventions Punctuation and spelling are conventional. Manuscript is properly prepared (margins are correct, title is provided, name and date are given, pages are numbered, and so forth). Exercise 13.2 The letter is filled with emotive language, insults and attacks. Since the letter was published in a newspaper with a wide readership, the author, it could be assumed, is attempting to persuade readers to accept his claim to oppose the tax increase and to vote against Democrats. Students will want to say that the letter is ineffective, but they might consider that the letter could be effective in convincing non-critical thinkers. Exercise 13.3 The two parts of this exercise provide topics and questions for students preparing an argument. Here are 120 additional topics and questions, most of which are intended to be topic-generators. Students must narrow the topic and refine the question when necessary. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.

Should the United States continue the war on drugs? Should marijuana be legalized for medicinal purposes? Should we end the practice of building homes and business on America’s coastlines? Are pollution laws too strict? Not strict enough? Is global warming myth or fact? Should the police be allowed to photograph people entering public events (as was done at the Super Bowl in 2001)? It’s often said that we are a “litigious society.” Are we? Should recycling laws be trimmed back, left alone, or increased? Should the United States pursue an antiballistic missile defense system? Should it be illegal to download music from the Internet? Should executions in high-profile cases (Timothy McVeigh's, for example) be televised? Should credit card companies be barred from advertising on college campuses? Should federal funds be available to church-run organizations that serve community needs? At what age should someone accused of a crime be tried as an adult? Should the United States pay reparations for slavery?


16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58.

Was the United States justified in going to war with Iraq in the Second Gulf War? Should the United States intervene in internal conflicts in other nations? Should the United States intervene in conflicts between other nations? Should defense spending be increased? Decreased? What limits, if any, should the federal government place on the Internet? Should pornography on the Internet be regulated? Do we need more gun control laws? Should the SAT be eliminated as a college admissions test? Does illegal immigration harm the economy? Is the private sex life of a political figure the public’s business? How relevant is one’s private life to public office? Should the U.S. have ratified the Kyoto Treaty? Should Congress institute term limits? Do we need campaign finance laws? Is space exploration a waste of money? Is there anything to faith healing? Is human cloning ethical? Do individuals have a right to die? When does “life” end? Is professional wrestling harmful to those who watch it? Should the government permit or prohibit physician-assisted suicide? Should old, unused nuclear power plants are being purchased and put back online? Should sex education be taught in public schools? Should condoms be distributed in public schools? Should parents who put a newborn up for adoption be allowed to change their minds? Are we too concerned with the rights of criminals? Is the victim ever responsible for the crime? Is animal experimentation justified? Is American culture on the decline? Is grade inflation a problem at your school? Should high school students be required to pass a standardized test before graduating? Do paramilitary organizations pose a threat against the government? Are the ACLU’s objectives too extreme? Can the government require some citizens to be sterilized? Should Division I athletes be paid? Do media portraits of women encourage eating disorders? Should endangered species take priority over property rights? Should tenure be abolished in public education? Should the media pay more attention to third political parties? Should third parties be invited to participate in televised debates? Should the Electoral College be eliminated? Are multicultural approaches good for education? Should gay couples be allowed to adopt children?


59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 76. 77. 78. 79. 80. 81.

82. 83. 84. 85. 86. 87. 88. 89.

Should some sports teams (Atlanta Braves, for example) be required to change their names? Do Barbie dolls give little girls the wrong impression? Is there any harm in beauty pageants? Should children (e.g., four or five years old) participate in beauty pageants? Should Americans curtail their consumption of beef? Have we made too much of sexual harassment? Should the government step in when parents refuse medical treatment for their children for religious reasons? Is Howard Stern dangerous? Should campuses institute speech codes? If so, what language should be prohibited? Are Catholic schools more successful than public ones? Is home schooling an effective way to educate children? Should the practice of circumcision be stopped? Should college students be required to take courses in a general education or core curriculum? Should college students be required by their schools to perform community service or take service learning courses? Should a mother whose child is born addicted to crack be charged with a crime? Should Pete Rose be admitted to the Baseball Hall of Fame? Should a singer whose lyrics are considered offensive to some groups be disqualified from awards competitions such as the Grammys? Should boxing be outlawed? Should Israel return any land to the Palestinians? Should the government outlaw some dog breeds? Should some dog breeds be exterminated? Is there anything wrong with an African American using what are normally considered racist terms? Should radar detectors be outlawed in all states? How serious (or widespread) are any of the following (some topics can be narrowed to the students’ hometown or campus): violence against homosexuals, violence among teenagers, domestic abuse, racism , discrimination, teen pregnancy, terrorism , nursing home abuse, hate crimes, homelessness, gang violence, media violence, pollution, gun violence, drug use and addiction, child abuse? Should Hooters restaurants be boycotted? Is plagiarism really all that bad? Should students with special needs be educated in classrooms with everyone else? Are sanctions against aggressor nations effective? Moral? Should tax money be used to fund art exhibits that some groups find offensive? Is gambling a victimless crime? Should doctors be prohibited from performing elective cosmetic surgery on teenagers who request it (e.g., on sixteen-year-old women requesting breast augmentation?) Have academic standards eroded?



Was the United States justified in dropping atomic bombs on Hiroshima and Nagasaki in World War II? 91. Is the Confederate flag a racist symbol? 92. Is the tobacco tax unfair? 93. Should high schools require an admissions test? 94. Should women be allowed to become Catholic priests? 95. Does the World Trade Organization present a threat to workers in developing nations? 96. Should the Brady Bill be eliminated? 97. What really happened at Roswell, New Mexico? 98. Should Martin Luther King Day be a day off for students in public schools? 99. Should a couple live together before they marry? 100. Are people who make long lists neurotic?

Some general topics that may be narrowed into an arguable thesis: 1. American isolationism 2. Globalization 3. The North American Free Trade Agreement 4. Non-traditional medical practices 5. The effect of free agency on professional sports 6. The advantages and disadvantages of widespread computerization 7. Computer ethics 8. The insanity defense 9. Performance enhancing drugs and athletics 10. The Olympics 11. Income tax reform 12. English as the “official language” 13. Oil companies and the environment 14. Nuclear proliferation 15. Dieting and weight control 16. Managed health care 17. Trade unions 18. The value of the literary “canon” 19. Children’s rights 20. Immigration reform Exercise 13.4 As written, this exercise assumes that arguments are being written by groups of students, but the advice in the exercise is applicable to individuals writing their own papers.


Exercise 13.5 This exercise invites students to consider that various approaches can be taken to the same topic. Exercise 13.6 This exercise assigns the paper. Grading Rubric Personally, we find traditional rubrics very hard to use when grading papers. Some categories unavoidably overlap, and we find most rubrics too limiting. They can also give the student a false sense that the very complicated and interwoven process of writing is reducible to a code. Nonetheless, the following rubric may be of use when grading arguments.








Writer addresses topic with enthusiasm and conviction and shows knowledge of subject matter (doesn’t merely string together quotes, for example). Tone is appropriate to topic.

Tone is okay, but essay lacks enthusiasm or conviction. Writer understands topic, but does not show total command over material (opting for quotes when paraphrases are more appropriate, for example).

Writer shows respect for readers, reconstructs opposing arguments fairly and charitably, and anticipates and answers readers’ reactions. Topic is important, interesting, controversial, or unusual and is narrowed appropriately. Central claim is clear; thesis is limited and defended throughout.



Writing is bland or pretentious, too casual or too formal. Writer sounds bored or antagonistic. Tone is inappropriate for topic. Writer needs to learn more about topic: much of the argument sounds like a rehash of conventional arguments and ideas. Writer shows respect Writer insults, berates, for readers and or ridicules reader. attempts to reconstruct Opposing arguments opposing argument are misrepresented, fairly and charitably. ignored, or dismissed Writer does not too easily. Writer anticipate all important, seldom if ever likely reactions. anticipates readers’ reactions. Topic is controversial Topic is trivial, but could be further common, or overdone. narrowed to allow for a Topic is too more interesting or complicated or too unusual (or large for the length of manageable) the argument. approach. Thesis is clear but Thesis is unclear. At could be further end of argument reader limited. Argument may cannot say, “This paper wander slightly from argues that _____.”) thesis. Thesis is too broad; argument does not stick to thesis.


Organizatio n (Form)

Development (Content)



Introduction is compelling. Body paragraphs present defense. Conclusion is effective. Overall pattern is effective and appropriate for topic and thesis. Paper proceeds smoothly from point to point.

Essay has a three-part structure, and organizational pattern is discernible, but a more effective pattern might have been chosen. Paper flows from point to point, with perhaps a few transitional problems along the way. Argument is supported but some support is weak, unreliable or incomplete. Key terms are not well defined. Some assumptions left unexamined. Obvious opposing arguments are left unanswered.

Paper seems aimless at points. Organization is unclear or ineffective. No overall pattern is discernible. Essay is not coherent.

Sentences are clear and grammatically sound. Sentences structures and length are varied. Words are used appropriately.

Some grammar errors are present, but the overall effect of the essay is not hampered. Not all words are used appropriately.

Punctuation and spelling are accurate throughout. Conventional manuscript format is used (e.g., font, margins). Appropriate documentation style is used.

Some errors in punctuation, spelling, and mechanics (e.g., margins, spacing), but the essay is still readable.

Grammar errors distract and impede the reader and cause misreading. Style is choppy and distracting. Misuse of words creates misreading. Enough errors to be distracting or cause confusion. Paper was not proof-read. Formatting is unconventional, annoying, or manipulated to make paper appear longer.

Argument is supported throughout with wellselected facts and opinions. Sources are credible. Premises and conclusions are connected logically (i.e., arguments are deductively valid or inductively strong). Fallacies are avoided. Assumptions are examined. Key terms are defined. Opposing arguments are rebutted convincingly.

Support is very weak, irrelevant, insufficient, or nonexistent. Fallacies or emotional appeals are present. Terms are undefined. Assumptions are unexamined. Opposing arguments are ignored. Overall argument is incomplete or difficult to understand.


The rubric can be handed to students when the argumentative essay is assigned, and the following grading sheet can be used to score papers. The sheet allows an evaluator to comment on what a student has done well and what might be done better next time. It provides room for comment on some or all of the various criteria listed under the main headings, so that, for example, a professor could compliment a student on his or her choice of an organizational scheme and still suggest a better pattern for defending the thesis. The instructor can also underline or circle relevant phrases and sentences in the left column. The drawback in using such a grading sheet is that the evaluator must take the time to write a short comment even in those areas where the student’s paper is strong. But because the comments in the grade sheet are bolstered by comments written in the margins of the student’s essay, the final comments can be short and allusive.


In the best papers

Writer The writer avoids appearing to merely fulfill an assignment and instead, writes honestly, with confidence, conviction, and enthusiasm, showing that he or she cares about the topic and the claim. The writer demonstrates understanding of the topic chosen for discussion and does not defend the claim with unexamined, usually erroneous premises that are the result more of habit than thought or research. The writer avoids sounding arrogant, overly aggressive, or pretentious and avoids egocentrism, sociocentrism, or wishful thinking. The writer uses a tone appropriate to the topic.

Audience The writer shows a keen sense of audience and does not insult, berate, or ridicule readers or use personal attacks against those who hold an opposing view. The audience is assumed to be slightly skeptical, open minded, intelligent, rational, humane and fair and is treated with respect. The writer anticipates reader’s reactions, especially those of potential opponents and renders opponents’ arguments accurately and charitably.

How your paper compares

Score 1-5


Topic The selected topic is controversial (or unusual), interesting, and narrow enough to be dealt with adequately in the space allowed. The writer avoids topics too complicated or too vast. Thesis The argument defends a single, central claim, usually expressed in a thesis statement provided in the opening paragraph. The thesis presents a position on the topic. The thesis is limited to the assertion that the writer intends to prove, and the essay does not digress from the thesis.


Organization (Form) The essay contains an interesting introduction, body paragraphs that develop the thesis, and an effective conclusion. The essay flows coherently from paragraph to paragraph. A pattern of development is clear throughout the essay. The pattern is logical, effective, and appropriate given the topic and the thesis. Opposing arguments are introduced and addressed at an appropriate point in the essay.

Development (Content) The central claim is defended with premises that are themselves, when necessary, supported with well-selected facts and opinions. Only credible sources are used. Premises and conclusions are connected logically. Fallacies are avoided. Assumptions are examined. Key terms are defined when necessary, and definitions are provided in a suitable manner. Opposing arguments are rebutted convincingly. Argument and subarguments are cogent or sound. The overall argument is complete.

Expression Sentences are clear, concise, and complete; the essay is free of grammatical errors. Sentence structures and lengths are varied to avoid a choppy style. Words are selected carefully and used correctly.


Conventions Punctuation and spelling are conventional. Manuscript is properly prepared (margins are correct, title is provided, name and date are given, pages are numbered, and so forth). Overall Assessment

Score: ____/40


Rubric for Critical Argumentation Skills 5

The writer’s main conclusion or thesis is clearly stated. The argument is supported throughout with credible, well-sustained evidence. Conclusions are supported by sound reasoning. Fallacies and logical inconsistencies are avoidable. Credible sources are used. Key terms are defined. Important assumptions are identified. Competing points of view are identified and examined fairly. Opposing arguments are addressed and rebutted convincingly. Implications and consequences are clearly identified and are amply supported by the evidence presented.


The writer’s main conclusion or thesis is clearly stated. With minor exceptions, the argument is supported with credible, well-substantiated evidence. Conclusions are supported by sound reasoning, but some minor logical lapses occur. Fallacies and logical inconsistencies are avoided. Credible sources are used. Key terms are defined, but not always with sufficient clarity. Assumptions are generally identified, but a few are left unexamined. Competing points of view are identified and with minor exceptions are examined fairly. Opposing arguments are stated fairly, but some arguments are not fully rebutted. Implications and consequences are identified and are substantially supported by the evidence presented.


The writer’s main conclusion or thesis is stated, but not with complete clarity. The argument is mostly supported with credible, well-substantiated evidence, but some claims are dubious. For the most part, conclusions are supported by sound reasoning, but some significant logical lapses occur. Fallacies and logical inconsistencies are generally avoided, but some fallacious and/or inconsistent arguments or claims are offered. A few sources are not credible. Key terms are generally well-defined, but some important terms are undefined or are defined imprecisely. Some important assumptions are left unexamined. Some points of view are not acknowledged or are not examined with complete fairness. Opposing arguments are generally stated fairly and rebutted convincingly, but some important opposing arguments are unexamined or are not successfully rebutted. For the most part, implications and consequences are identified and adequately supported by the evidence presented.


The writer’s main conclusion or thesis is stated, but is unclear or varies as the argument develops. Some parts of the argument are supported with credible, well-substantiated evidence, but significant portions are not. A number of conclusions are not supported by sound reasoning. Some major fallacies and/or logical inconsistencies are committed. A number of sources are not credible. Several important key terms are left undefined. Some significant assumptions are unidentified. A number of key


competing points of view are unidentified or are not examined fairly. Some important opposing arguments are unexamined, stated unfairly, or not sufficiently rebutted. Some notable implications and consequences are unidentified or not sufficiently supported by the evidence presented. 1

The writer fails to state his or her main conclusion or thesis. The argument is not supported with credible, well-substantiated evidence. Conclusions are not supported by sound reasoning. Several major fallacies and/or logical inconsistencies are committed. Many sources are not credible. Key terms are undefined. Important assumptions are unidentified. Competing points of view are unidentified or are examined unfairly. Opposing arguments are unexamined, stated unfairly, or not adequately rebutted. Implications and consequences are unidentified or are poorly supported by the evidence presented. Rubric for Critical Evaluation Skills


The writer clearly identifies the main point or conclusion of the argument. Key supporting arguments are identified clearly, accurately, and completely. The writer identifies key assumptions, concepts, and implications of the argument, and is sensitive to the author’s purpose(s) and points of view. The writer’s evaluation of the supporting arguments is specific, thorough, and cogently argued. The writer’s overall evaluation of the argument is stated clearly and is fully supported by the arguments provided.


The writer identifies the main point or conclusion of the argument. The main supporting arguments are, with minor lapses, identified clearly, accurately, and completely. The writer identifies key assumptions, concepts, and implications of the argument, and is substantially sensitive to the author’s purpose(s) and point of view. The writer’s evaluation of the supporting arguments is specific, through, and substantially cogent. The writer’s overall evaluation of the argument is stated clearly and is strongly supported by the arguments provided.


The writer substantially identifies the main point or conclusion but fails to describe it with complete accuracy. The main supporting arguments are generally identified correctly, but not as clearly, accurately, or completely as in level 4 or 5. The writer identifies key assumptions, concepts, and implications of the argument adequately but not completely, and is generally sensitive to the author’s purpose(s) and point of view. The writer’s evaluation of the supporting arguments is substantially sound, but there are some notable deficiencies in terms of clarity, thoroughness, and cogency. The writer’s overall evaluation of the argument is stated more or less clearly and is generally supported by the arguments provided.



The writer more or less identifies the main point or conclusion, but fails to describe it accurately or completely. The main supporting arguments are generally identified correctly, but some key arguments are unidentified or are identified vaguely or inaccurately. The writer fails to identify some key assumptions, concepts, and implications of the argument, and largely misreads or fails to grasp the author’s purpose(s) and point of view. The writer’s evaluation of the supporting arguments, while not wholly unsatisfactory, contains serious deficiencies in terms of clarity, thoroughness, and cogency. The writer’s overall evaluation of the argument is not stated clearly and precisely, and is not strongly supported by the arguments provided.


The writer fails to identify the main point or conclusion. The writer fails to identify all or most of the main supporting arguments or identifies them vaguely or inaccurately. The writer fails to identify key assumptions, concepts, and implications of the argument, and fails to grasp the author’s purpose(s) and point of view. The writer’s evaluation of the supporting arguments is seriously deficient in terms of clarity, thoroughness, and cogency. The writer fails to state an overall evaluation of the argument or states it very unclearly. The arguments offered to support the overall evaluation are weak and provide little or no support for the conclusion.


Chapter 14: Thinking Critically about the Media It is important to note that this chapter is not, and does not pretend to be, a course in media studies, which is obviously a complicated and sophisticated field of inquiry that could hardly be summed up in a few dozen pages. The focus of this chapter is on the student as a consumer of news from the mainstream press and a target of advertisers. We have limited our analysis of the media to the way news and advertising might best be digested by a student of critical thinking who values those standards mentioned in Chapter 1: clarity, precision, accuracy, relevance, consistency, logical correctness, completeness, and fairness. Rather than argue that the news media and advertisers are unconcerned with such standards, we contend that a critical thinker must recognize that the standards are often violated, even inadvertently, by the media’s need to reach a large audience and to keep that audience interested. We start with a discussion about what we see as the central problem that results in the media’s emphasis on reaching and holding a large audience—the lack of context in which complicated and significant events can be fully understood. Removing events from their contexts does much damage to such critical thinking standards as clarity, accuracy, relevance, completeness, and fairness, and we ask students who value those standards to recognize, first, that the news is not always clear, accurate, relevant, complete, and fair, and, second, that a consumer of news and advertising must struggle to maintain those standards in the onslaught of news and advertising images and messages. Most of the exercises in this chapter are collaborative. With few exceptions, there are no right and wrong answers for the exercises in this chapter. The objective is to provide students with a more sophisticated understanding of the media through an active engagement with the products of the media. Exercise 14.1 This exercise emphasizes the point that the mass media tends to remove issues from their broader contexts and to deliver abbreviated messages that might be confusing, open to interpretation, or misleading. Students might be reminded that the purpose of the exercise (and the chapter) is not to disparage the media or to suggest that the media are consciously manipulating readers and viewers. With limited time on news broadcasts and limited space in magazines and newspapers (pages can be added, but only at greater expense), the media must be selective in deciding how to pare a story. This exercise asks students to select several newspapers to compare the attention each gives to a common story. Students are asked in the exercise to consider what questions an interested reader might have after encountering an interesting but undeveloped item in a paper. This is a good time to ask students if they generally pursue information beyond what they read in the daily paper or hear on the local news. As the first exercise in the chapter, this is a good place to discuss the standards of critical thinking mentioned in chapter 1, especially completeness and accuracy. Students might be asked, also, how usually incomplete news items can help prop up some of the barriers to critical thinking. With the limited


information we get from a news source and, failing to investigate further, do we sometimes feed our self-serving biases, for example? Exercise 14.2 To demonstrate that different publications target different audiences, this exercise asks students to compare the advertisements in several media sources. For some students, the exercise is an eye-opener if only because they are unfamiliar with publications other than the most recognized newsmagazines and popular magazines (unless, of course, they were introduced to journals of opinion in Chapter 12). Exercise 14. 3 The three parts of this exercise require students to look closely at how the media’s selection of topics often reveals a common thread of conflict and emotional appeal. Students might be reminded in this exercise that conflict in itself does not make a topic unworthy, that, instead, conflicts are often important stories, and that few of us want a news media that focuses solely on pleasant topics. The objective of the exercise is to show that some media sources heighten conflict to grab and hold our attention. Similarly, many stories are selected only for their entertainment value, as alert students will discover in their completion of the exercise. Exercise 14.4 This exercise provides a facts-only list and asks students to write two articles with contrasting effects on the audience. This exercise is one of the most effective in helping students understand the power of language, selection and organization. It’s important that students are cautioned against revealing their opinion too openly; they don’t want to say, “Daria is a loser.” And they shouldn’t falsify anything or add facts not listed. The writer must achieve his or her intended effect subtly. Exercise 14.5 Many students have strong opinions on the subject of media bias. This exercise gives students an opportunity to air their views on media bias and objectivity in dialogue with others.


Exercise 14.6 Although many students do not read a daily paper and seem at times uninterested in starting the habit, they will generally read the school paper, which provides a gold mine for applying the lessons of this chapter. Exercise 14.7 I. This exercise used to work well on our campus, because until recently free copies of the New York Times, USA Today, and two local papers were available to all students, faculty, and staff. Unfortunately, this noble attempt to foster current-affairs literacy fell victim to the budget ax. II. This exercise is useful primarily in alerting students to the audience corporate advertisers target in network news broadcasts. Exercise 14.8 This exercise encourages reflection on some key ethical issues in advertising. Exercise 14.9 1. f 2. o 3. h 4. k 5. a 6. x 7. l 8. d 9. i 10. c 11. l 12. t 13. n Exercise 14.10

14. g 15. v 16. u 17. e 18. m 19. w 20. y 21. r 22. s 23. p 24. q 25. b


I. and II. These exercises help students recognize common advertising ploys. III. 1. Weasel word (“fights”) 2. Anxiety ad 3. Feel-good ad; image ad 4. Catchy slogan 5. A fine-print disclaimer that definitely should not be overlooked 6. Puffery 7. Humor 8. Catchy jingle 9. Puffery 10. Emotive words 11. Fine-print disclaimer 12. Celebrity appeal and puffery 13. Sex appeal 14. Puffery and catchy jingle 15. Image ad 16. Anxiety ad 17. Puffery 18. Fine-print disclaimer 19. Catchy slogan 20. Puffery and emotive words 21. Image ad and emotive words 22. Anxiety ad 23. Image ad 24. Feel-good and image ad 25. Sex appeal


Chapter 15: Science and Pseudoscience Exercise 15.1 1. Select a large number of persons suffering from chronic back pain. Randomly divide them into an experimental group and a control group. Then perform a series of doubleblind experiments using real and phony magnets. If members of the experimental group report significantly greater pain relief than do members of the control group, that would support the hypothesis. Note that because the hypothesis is so vague, a large number of experiments would need to be performed in order to effectively falsify the hypothesis. Tests would need to be performed involving magnets of various sizes and strengths, various placements on or around the body, different lengths of treatment, and so forth. 2. The most reliable way to test this hypothesis is by means of a randomized experimental study. For ethical reasons, however, a nonrandomized prospective or retrospective study would probably be preferable. 3.This hypothesis can be tested by means of a long-term randomized experimental study. 4. Obviously, for both practical and ethical reasons, carefully controlled experimental studies cannot be conducted on the sex lives of teenagers. However, we can conceive of ethical and reasonably reliable prospective or retrospective studies that would confirm or refute the hypothesis. Such studies would have be very large and very sophisticated to control for other variables. Note also that the phrase "safe sex education" is vague and would need to be defined more precisely before the hypothesis could be effectively tested. 5. This hypothesis can be tested by means of a nonrandomized retrospective study. Select a large, representative sample of Vietnam veterans with children. Randomly divide these into two groups: an experimental group of Vietnam veterans with children who were exposed to Agent Orange and a control group of Vietnam veterans with children who were not exposed to Agent Orange. If the children of members of the experimental group exhibit birth defects at significantly higher rates than do children of members of the control group, this would support the hypothesis. Note, however, that it would be very difficult to control for other variables. Exercise 15.2 1. Not testable. The claim is not realistically verifiable or falsifiable, though scientific evidence no doubt bears on the issue. 2. Not testable. Angels, if they exist, are supernatural beings that cannot be studied by scientific methods. Beliefs about guardian angels are typically based on the Bible, church teaching, or personal religious experiences. None of these grounds is a proper basis for scientific conclusions.


3. Testable. Take two sets of identical razor blades. Store them for various lengths of time under identical atmospheric and other conditions, except that one set of blades is placed under pyramids of various sizes and materials and the other set is not. Then test the sharpness of the blades in a way that can be precisely measured and is not subject to experimenter bias. 4. Not testable (value statement). 5. Not testable. Because all possible evidence that might tend to show that the claim is false is, by hypothesis, thoroughly deceptive, the claim is not falsifiable. 6. Testable. It's easy to imagine evidence that would verify the claim--for example, if the carcass of a large Plesiosaur washed up on the shores of Loch Ness. Falsifying the claim is much more difficult. However, we can imagine scientific observations or tests that would show beyond a reasonable doubt that no such monster exists. For example, extensive sonar, photographic and underwater searches might find no evidence that any Plesiosaur-like creatures live in the Loch. Similarly, scientific studies might show that there is too little food in the Loch to support a breeding population of large predators. 7. Not testable. We can imagine evidence that would falsify the claim--superintelligent extraterrestrials might visit the earth, for example--but the claim is not realistically verifiable, because we have no way to search the immensity of space. 8. Not testable. Claims about existential or cosmic purposes are not scientifically testable. 9. Not testable. The claim is too vague to be tested and too general to allow any testable conclusions to be drawn about the alleged psychic abilities of the reader. 10. Not realistically verifiable. Not only would tree-counters have to resolve difficult borderline cases (“Is this a tree or a bush?” “Is this scraggly looking tree dead or alive?”), but there is no way, even with an army of counters, that all living trees in Canada could be located (many are in remote areas, growing in tall grasses, hidden under leaves, etc.). And even if these obstacles could somehow be overcome, any ongoing count would be continually invalidated by the growth of new trees and the deaths of others. 11. Testable only if "fundamentally selfish" is given a clear, empirically observable meaning. Upon close examination, it often turns out that those who assert this claim often define selfish in such a way that the claim is either trivially true or empirically unfalsifiable. See Joel Feinberg's "Psychological Egoism," in Joel Feinberg, ed., Reason and Responsibility: Readings in Some Basic Problems of Philosophy, 8th ed. (Belmont, CA: Wadsworth, 1993), pp. 461-72, and in later editions, for a classic discussion. 12. Testable to some extent. Find a representative sample of patients suffering from some often-curable disease (e.g., breast cancer). Randomly divide them into experimental and


control groups. Then conduct a double-blind experiment in which all the patients are treated exactly the same except that one group is prayed for by a group of intercessors and the other group is not. (To make the experiment really interesting pick a variety of intercessors: evangelical Christians, liberal Catholics, Mormons, Hindus, Wiccans, and perhaps even some atheists or agnostics.) Then check to see whether members of the experimental group(s) are cured at higher rates than the control group(s). Note, however, that it's not probably impossible to perform tightly controlled tests of this hypothesis. Most seriously ill patients have at least some friends or relatives who are praying for them. Moreover, religious individuals throughout the world are constantly offering generic prayers for the sick. How could scientists possibly determine which of these prayers, if any, are truly efficacious? 13. Not testable. If absolutely everything in the universe doubled in size--including all rulers and other standards of measurement--there would be no way to detect the difference. Exercise 15.3 1. Pseudoscientific thinking. The arguer relies on an appeal to personal experience (“I tried it and it worked.”) The herbal tea might have worked because of the placebo effect. Alternatively the headache might have gone away by itself. 2. Pseudoscientific thinking. The prophecy is so vague that any number of historical events could plausibly be interpreted as fulfilling it. 3. Pseudoscientific thinking. What reason do we have for thinking that any of these claims are true? How could we verify that the original copy of the letter is in New England or that a "Mr. Fairchild" died nine days after receiving the letter? Even if these claims are true, why should we think the letter had anything to do with the good or bad luck these individuals experienced? Chain letters are so common that, just by chance, many people must encounter good or bad luck within days of receiving the letter. Finally, the claim that you will receive "Good Luck" in the mail "in four days" is both vague and ambiguous. It is vague because it is unclear what counts as good luck. It is ambiguous because it is unclear whether "in four days" means "within four days" or "on the fourth day." 4. Pseudoscientific thinking. The arguer is explaining away falsifying evidence. 5. The analogy is a poor one. When scientists disagree, they generally disagree about matters on the frontiers of scientific knowledge, not about fundamentals. The disagreements among psychics and other practitioners of pseudoscience tend to be much deeper and more systemic. 6. On the contrary, mere coincidence is the best explanation of "precognitive" events such as these. Just by chance, one would expect striking coincidences of this sort to be


reported occasionally. Moreover, there is a natural human tendency to remember premonitions that turn out to be true and forget those that turn out to be false. 7. Pseudoscientific thinking. The graphologist is relying upon general, Barnum-type language that applies to practically everybody. 8. Pseudoscientific thinking. The claim that nothing bad ever happens to a person unless he or she has done something bad, either in this life or a previous life, is unfalsifiable. 9. Pseudoscientific thinking. The cardinal is ignoring falsifying evidence, is refusing to engage in empirical research, and is dogmatically committed to a static worldview. 10. Pseudoscientific thinking. Parry is explaining away falsifying data. 11. Pseudoscientific thinking. Earl is explaining away falsifying data, and his claim that aliens are much too advanced to ever be detected by us renders his claim unfalsifiable. 12. Pseudoscientific thinking. Given the way the arguer qualifies her claim, it's unclear what possible evidence she would accept as counting against her claim that God always answers prayers. 13. Pseudoscientific thinking. It’s not surprising that dowsing sometimes works, given that underground water is abundant. However, the only way to know whether dowsing consistently works is to test it under controlled conditions. 14. This argument commits the fallacies of attacking the motive and ignoring falsifying data. In fact, legions of independent scientists would jump at the chance to achieve international renown by proving the validity of such a miracle cure, if there were any reason for thinking that such a cure actually works. 15. Pseudoscientific thinking. Claims about the “esoteric meaning[s]” of music are not scientifically testable. Exercise 15.4 I. Daily newspaper horoscopes are targeted at younger, less affluent, less educated audiences. As you would expect, therefore, they rarely contain predictions or personality profiles targeted at very young readers ("avoid finger-painting today") or senior citizens ("favorite singer: Englebert Humperdink"). II.


Students enjoy this exercise, and it can be done very quickly. To make it a fair test, it's important that all twelve horoscopes contain genuine predictions. The person who collects the horoscopes may need to consult several newspapers or astrology Web sites to find suitable material. Exercise 15.5 I. After reading this section, most students readily agree that astrology is a pseudoscience. You may need to play devil's advocate a bit to generate a good discussion. II. Here's one obvious way to conduct such a study: Check hospital maternity records at large hospitals around the country to find unrelated persons born in the same hospital at the same time on the same day. (Obviously, this would be an enormous chore, but in principle it could be done.) Track down as many of these people as you can and ask them to take the Minnesota Multiphasic Personality Inventory or some other standard personality test. Check to see if the time twins exhibit similar personality traits at rates higher than one would expect by chance. Finally, check death records to see if there are any nonchance correlations between deceased time twins' dates of death.


Appendix: Essays for Critical Analysis Here are one reader’s standardizations of these arguments. Essay 1 Congress Nears Choice: Protect Freedom or Stoke Anger? USA Today 1. The three recent episodes of flag desecration are minor, rare and easily addressed by local laws. 2. Thus, they hardly require the extraordinary act of amending the Constitution. (from 1) 3. The First Amendment is the reason Americans are free to say what they think. 4. [This freedom includes the right to desecrate the flag as a way of protesting and expressing grievances.] 5. To limit this freedom by making flag desecration unconstitutional is to say that the American right to freedom of expression is no longer as sacrosanct as it should be. 6. If Congress banned something as pathetic as flag desecration to score political points, surely it would consider limiting other forms of unpopular speech, such as flying a flag upside down, that are important, nuanced forms of political dissent. 7. Treating flag desecration as a minor criminal offense, as in the case of the Connecticut flag burner, is sufficient. 8. The flag itself stands for a nation that deems individual liberties so important, it tolerates unpopular minority opinion. 9. The major threat to the flag comes not from the occasional flag burning of Old Glory but from those who would sacrifice the principles the flag represents. 10. [We should not sacrifice these important principles of freedom of expression.] 11. Therefore, Congress should not amend the Constitution to make flag burning unconstitutional. (from 4-10)


Essay 2 Legal Steroids the Solution Rick Hurd 1. Roger Clemens, like almost every modern athlete, has used performance enhancing drugs. 2. The Mitchell report proves this beyond a reasonable doubt. 3. Thus, baseball has never been more sick, and its players never more shad. (from 1-2) 4. The use of performance-enhancing drugs is a runaway fire. 5. The testers are the firemen desperately trying to catch up. 6. Thus, it is time to take a new approach. (from 4-5) 7. Seasons start in mid-February and can run as long as early November. 8. Fewer double-headers mean fewer days off. 9. A tem can play one game at night on the East Coast, then play early the next evening on the West Coast. 10. Thus, the body is subject to punishment that didn’t even exist 30 years ago. (From 79) 11. Thus, performance enhancers have become necessary. (from 9-11) 12. It would seem the greater hazard would be to allow baseball to keep on keepin’ on. 13. Not allowing legal juicing but requiring players to prove their innocence by following the cheaters or go through the back alleys to keep up seems to be cruel and unusual. 14. Therefore, it’s time for Major League Baseball to consider making performanceenhancing drugs a welcome, and legal, part of its culture. (from 12-13) Essay 3 Age 18 Isn’t the Answer USA Today 1. More than 100 college presidents claim that keeping the drinking age at 21 prevents young adults from learning responsible drinking at home.


2. That when students arrive on campus, they can’t drink sociably and moderately in bars and restaurants, so they overindulge in dorm rooms and private houses. 3. Thus, the presidents argue that the drinking age should be lowered from 21 to 18. (from 1-2) 4. But lowering the age to 18 would kick the problem down to the high school level, where 18-year-olds would buy alcohol for younger friends an siblings who can pass for 18 with their own fake IDs. 5. Since 1984, the year Congress effectively set a national drinking age at 21 by withholding highway money from any state with a lower age, an estimated 25,000 lives have been saved. 6. After the drinking age rose from 18 to 21, traffic fatalities dropped by 16%. 7. Thus, when young people drink, traffic fatalities rise sharply. (from 4-6) 8. While higher drinking age does create enforcement headaches for college administrators, by asking for a lower drinking age they are just trying to wash their hands of the problem. 9. Officials at the University of Virginia used an informative campaign to significantly drop alcohol-related incidents there without lowering the drinking age. 10. Therefore, the college presidents rather than passing the buck should likewise seek better options and not advocate lowering the drinking age to 18. (from 7-9). Essay 4 Opposing View: Law Makes Matters Worst David Oxtoby 1. Americans under 21 are drinking in great numbers, drinking in secret, frequently drinking to excess, too often drinking themselves into an emergency room. 2. Americans under 21 are doing this in spite of the most determined efforts of college administrators across the country to prevent it. 3. They are doing this in defiance of the law. 4. [Thus, a change in the status quo is necessary.] (from 1-3)


5. Current drinking age laws force college-age drinking out of the open, where it can be monitored and moderated, behind closed doors, where young people can put themselves and others at even greater risk. 6. Recent years have shown a significant increase in binge drinking, leading to alcohol poisoning and causing hundreds of deaths per year. 7. Thus, the truth is that current drinking laws are not merely failing our children; they’re making matters worse. 8. An American student returning from a study-abroad semester in Spain reported that students thee drank occasionally, unlike American students whom he said had an “obsession” with alcohol. 9. An 18-year old can die for his country but cannot legally buy a glass of beer. 10. Therefore, this is a vital issue and although there are many factors to consider, we might find that some form of lowered age, combined with effective education, could reduce the drinking problems in America today. 17. Imploring people to eat better and exercise more has been the default approach to obesity for years but that is a failed experiment. 18. Thus, the personal-responsibility argument is not helpful. (from 17) 19. The personal-responsibility is startling similar to the tobacco industry’s efforts to stave off legislative and regulatory interventions. 20. The nation tolerated personal-responsibility arguments from Big Tobacco for decades, with disastrous results. 21. Thus, the personal-responsibility argument is a trap. (from 19-20) 22. Governments collude with industry when they shift attention from conditions promoting poor diets to the individuals who consume them. 23. [Government has the responsibility to protect and promote the health of the people.] 24. Therefore, government should be doing everything it can to create conditions that lead to healthy eating, support parents in raising healthy children, and make decisions in the interest of public health rather than private profit. (from 10-23) Essay 5


Why Parents Shouldn’t Teach Their Kids to Believe in Santa Claus David Kyle Johnson 1. Parents lie when they teach their kids to believe in Santa Claus. 2. Lying is immoral unless it’s justified by a very noble cause (e.g., saving someone’s life). 3. Parents teach their kids to believe in Santa Claus because it’s fun to watch their kids get excited—hardly a noble cause. 4. So, it’s immoral for parents to teach their kids to believe in Santa Claus. (from 1-3) 5. When kids find out that Santa is a myth, they often get mad at their parents for deceiving them. 6. To perpetuate the Santa Claus myth, parents have to tell their kids to shut off their brains and just believe. 7. Some kids are frightened by the idea of Santa’s secretive chimney entry. 8. So, it’s harmful for parents to teach their kids to believe in Santa Claus (from 5-7). 9. Therefore, parents should not teach their kids to believe in Santa Claus. (from 4 and 8) Essay 6 Defending My Right to Claim My “Steak” in the Animal Kingdom Jack Pytleski 1. I’m going to die no matter what I eat. 2. I want to enjoy every minute of my allotted time on earth. 3. If given a choice between sitting around drooling in a “personal care center” or checking out earlier from a massive heart attack, I would choose the latter. 4. I have a right to do as I please with my own body. 5. I have a constitutional right of privacy that gives me the right to eat the kinds of foods I enjoy. 6. [Thus, contrary to one popular argument for vegetarianism, the fact that eating a balanced vegetarian diet tends to be healthier than a meat-based diet is not a good reason for me to switch to a vegetarian diet (from 1-5)].


7. I believe on faith that animals were put on earth to provide food, clothing and other benefits to humans. 8. [Thus, contrary to a second popular argument for vegetarianism, animals have no right not to be killed and eaten by humans (from 7)]. 9. [Therefore, two popular arguments for vegetarianism – the health benefits argument and the animal rights argument – do not provide good reasons for adopting a vegetarian diet (from 6 and 8)]. Essay 7 New Immigration Laws Expose Downside of Getting Tough USA Today 1. When Congress gave up trying to pass a balanced immigration law last year, it opened the door for states, counties, and towns to write their own immigration laws. 2. Thus, the result has been a disquieting national experiment in handling illegal immigration almost solely with arrest and deportation. (from 1) 3. Oklahoma, which has one of the toughest new laws, now bars illegal immigrants from receiving state services. 4. It requires employers to verify that new workers are legal. 5. It gives people a way to sue companies that hire illegal immigrants. 6. It makes it a felony to transport, harbor, or conceal an illegal immigrant. 7. Thus, the law was meant to be harsh, and it is. (from 3-6) 8. Oklahoma Hispanic groups estimate that as many as 25,000 left the state after the law was approved last year. 9. School attendance dropped, workers disappeared, church attendance shrank and Latino businesses lost customers. 10. Thus, the law is undeniably effective (from 8-9) 11. The immigrants came not to rob banks but to improve their lives through hard work. 12. Yet families are uprooted, and parents are separated form their kids.


13. Thus, what’s missing is simple humanity—a recognition that the vast majority of those affected lack any malicious intent. (from 11-12) 14. When spouses, parents or children are illegal, a relative van be placed at risk for “harboring” them at home or “transporting” them to church. 15. There are persistent reports that police in some places target Hispanic drivers for roadside stops and document checks. 16. Some citizens have taken to carrying passports or birth certificates to avoid being jailed. 17. Thus, legal residents are hurt, too. (from 14-16) 18. Employers say they’re being asked to become immigrant police with imperfect tools. 19. A study in Oklahoma predicted that the law could cost the state’s economy more than $1 billion a year. 20. A firm that specializes in finding new locations for businesses said some companies have crossed Oklahoma off their lists. 21. Thus, by intent, the laws have hit businesses, which have scrambled to replace lost workers. (from 18-20) 22. The nation doesn’t want illegal immigrants, but it does want the cheap labor they provide. 23. So it passes laws then doesn’t pay to enforce them. 24. Thus, if there’s a virtue in all this, it is to highlight the hypocrisy that has long been at the heart of the ineffectual federal immigration law. (from 22-23) 25. President Bush’s immigration bill would have toughened workplace enforcement with a strong verification system and effective ID requirements. 26. It would have also acknowledged reality by fostering a temporary worker program and providing a rigorous path to citizenship for the most qualified of the estimated 12 million illegal immigrants here. 27. Thus, President Bush’s immigration bill is still a worthwhile proposal. (from 25-26) 28. [Therefore, while harsh laws such as Oklahoma’s may be satisfying to those who seethe over illegal immigration, they have many downsides and demonstrate the need for


comprehensive immigration reform like that which President Bush proposed.] (from 13, 17, 21, 24, and 27)


Note: The following treatment of the counterexample method of proving invalidity originally appeared in the first edition of Critical Thinking: A Student’s Introduction. It was cut for reasons of economy, but here, through the magic of cyberspace, it is restored for instructors who—like us—lamented its excision. TESTING FOR VALIDITY Deciding whether an argument is valid or not can sometimes be a tricky business. In this section we present an informal three-part test that can be used to test arguments for validity. We call it the Three C’s test.

The Three C’s Test for Validity Step 1: Check to see whether the premises are actually true and the conclusion is actually false. If they are, then the argument is invalid. If they are not, or if you can’t determine whether the premises and conclusion are actually true or false, then go to Step 2. Step 2: See if you can conceive a possible scenario in which the premises would be true and the conclusion false. If you can, then the argument is invalid. If you can’t, and it’s not obvious that the conclusion follows validly from the premises, then go to Step 3. Step 3:Try to construct a counterexample—a special kind of parallel argument—that proves that the argument is invalid. If you can construct such a counterexample, then the argument is invalid. If you can’t, then it’s usually safe to conclude that the argument is valid.

Let’s look at each of these steps in turn. Step 1 A valid argument is an argument in which it’s impossible for the conclusion to be false if the premises are true. Thus, the simplest test for validity is to check whether the premises are actually true and the conclusion is actually false. If they are, then the argument is invalid. Example:


If Michael Jordan was the world’s greatest baseball player, then he was a great athlete. Michael Jordan was a great athlete. Therefore, Michael Jordan was the world’s greatest baseball player. Here the two premises are in fact true and the conclusion is in fact false. Thus, we know immediately that the argument is invalid. Unfortunately, since invalid arguments can have any combination of truth or falsity and valid arguments can have any combination except true premises and a false conclusion, Step 1 tells us nothing about the validity or invalidity of arguments that do not have the particular combination “true premises and false conclusion.” For such arguments, we must turn to Step 2.

Step 2 Step 2 involves a kind of thought experiment. Since a valid argument is an argument in which it’s impossible for the conclusion to be false if the premises are true, we can show that an argument is invalid if we can imagine any logically possible circumstances in which the premises are all true and the conclusion is false. An example: Professor Butterfingers was working on a hydrogen bomb when it accidentally exploded in his face. Therefore, Professor Butterfingers is dead. Can we imagine any situation, however unlikely or improbable, in which the premise of this argument is true and the conclusion is false? Sure. Perhaps Professor Butterfingers is actually an indestructible robot in disguise. Or maybe some orbiting extraterrestrials decide to beam him up to their spacecraft just as the bomb explodes. Lots of things could conceivably happen that would cause the premise to be true and the conclusion false. Thus, the conclusion does not follow logically from the premise. Hence, the argument is not deductively valid. A second example:


Millions of Americans are Democrats. Millions of Americans are blondes. Therefore, at least some American Democrats must be blondes. Here again it’s not difficult to imagine circumstances in which the premises are true and the conclusion is false. (Imagine a possible world, for instance, in which, for some strange reason, it’s illegal for blondes to be Democrats.) The mere fact that we can imagine such a world shows that the conclusion does not follow necessarily from the premises. Unfortunately, thought experiments of this kind only work when one can clearly imagine a set of circumstances in which the premises are all true and the conclusion is false. Sometimes, however, we encounter arguments (e.g. logically complex arguments) when it’s difficult to do this. For arguments of this sort, we must turn to Step 3.

Step 3 Step 3 also involves a kind of thought experiment, but one that is slightly more elaborate than the kind of thought experiment described in Step 2. In Step 2 we ask: Is there any conceivable way that this particular argument could have all true premises and a false conclusion? In Step 3 we ask: Is there any conceivable way that any argument with this particular logical pattern could have all true premises and a false conclusion? If the answer to either question is “yes,” then the argument is invalid. Step 3 involves use of a procedure known as the “counterexample method of proving invalidity.” This method requires some ingenuity, but is basically very simple once you get the hang of it. The method involves two steps: (1) Determine the logical pattern, or form, of the argument that you’re testing for invalidity, using letters (A,B,C, etc.) to represent the various terms in the argument.


(2) Construct a second argument that has exactly the same form as the argument you’re testing, but where the second argument has premises that are obviously true and a conclusion that is obviously false.

The method works because with a valid argument you can never have true premises and a false conclusion. Thus, any time you find an argument that has true premises and a false conclusion, you know immediately that it is invalid. And because validity is determined by the logical form of an argument rather than by the actual truth or falsity of the premises and conclusion, you also know immediately that any argument that has that form must also be invalid. Thus, if you can find just one counterexample (i.e., one argument of that form that has all true premises and a false conclusion), then you can prove that all arguments that have that form are invalid. Let’s now apply the counterexample method to a few simple examples. Suppose we want to determine whether the following argument is valid or invalid: Example 1:

Some Republicans are conservatives, and some Republicans are pro-choice. So, some conservatives are pro-choice.

The first step in the counterexample method is to determine the logical form of the argument. To make sure that we are representing the form of the argument correctly, it is helpful if we begin by numbering the steps in the argument, with the conclusion stated last. We thus get: 1. Some Republicans are conservatives. 2. Some Republicans are pro-choice. 3. Therefore, some conservatives are pro-choice. (Note that in logic “some” always means “at least one,” i.e. “some and perhaps all.” “Some” never means “some but not all.” Thus, in logic, when we say “Some dogs


are animals” we mean “At least one dog is an animal” (which is true), not “Some, but not all, dogs are animals” (which is false).) Next, we assign letters to represent the various terms in the argument. Using “As” to represent “Republicans,” “Bs” to represent “conservatives,” and “Cs” to represent “people who are pro-choice,” what we get is: 1. Some As are Bs. 2. Some As are Cs. 3. Therefore, some Bs are Cs. This is the logical form of the argument in Example 1. Having determined this form, we have completed the first step of the counterexample method. The second step in the counterexample method involves attempting to construct a second argument that has exactly the same form as our argument being tested, but which (unlike the first) has obviously true premises and an obviously false conclusion. With most invalid argument forms, it is possible to construct such a counterexample using a few stock terms, such as “dogs,” “cats,” “animals,” “men,” “women,” “people,” “apples,” “pears,” and “fruit.” Using the terms “animals” as a substitute for “As,” “dogs” as a substitute for “Bs,” and “cats” as a substitute for “Cs,” we can construct an argument that has the same form as the argument in Example 1, but which has clearly true premises and a clearly false conclusion: 1. Some animals are dogs. (true) 2. Some animals are cats. (true) 3. Therefore, some dogs are cats. (false) We have thus constructed a counterexample to the argument in Example 1. Other counterexamples that would work equally well include: 1. Some fruits are apples. (true) 2. Some fruits are pears. (true)


3. Therefore, some apples are pears. (false) 1. Some politicians are Democrats. (true) 2. Some politicians are Republicans. (true) 3. Therefore, some Democrats are Republicans. (false) Let’s now try another example: Example 2:

If God exists, then life has meaning. Hence, God does exist, since life has meaning.

First, we begin by numbering the premises and the conclusion. 1. If God exists, then life has meaning. 2. Life has meaning. 3. Therefore, God exists. We next identify the form of the argument. Using “A” to represent the statement “God exists,” and “B” to represent the statement “Life has meaning” we get: 1. If A then B. 2. B 3. Therefore, A. Finally, attempt to find an argument that has exactly the same form, but one that has obviously true premises and an obviously false conclusion. For starters, we might try: 1. If Lassie is a dog, then Lassie is an animal. (true) 2. Lassie is an animal. (true)


3. Therefore, Lassie is a dog. (true) But this won’t work, because we need a false conclusion in order to get a good counterexample. Next, we might try: 1. If JFK was killed by a lone assassin, then JFK is dead. (true) 2. JFK is dead. (true) 3. Therefore, JFK was killed by a lone assassin. (true??false??) But this won’t work either, because for an effective counterexample we need a conclusion that is obviously false (i.e., one that is known to be false by practically everyone), and it is far from obviously false that JFK was killed by a lone assassin. So, back to the drawing board one more time: 1. If Kansas City is in California, then Kansas City is in the United States. (true) 2. Kansas City is in the United States. (true) 3. Therefore, Kansas City is in California. (false) Bingo! This gives us the counterexample we’re looking for. Now we’ve proven that Example 2 does not have a valid argument form, and thus is invalid. Another counterexample might be. 1. If George Washington died in a car crash, then George Washington is dead. (true) 2. George Washington is dead. (true) 3. Therefore, George Washington died in a car crash. (false) A third and final example:


Example 3:

Some senators are Republicans. Hence, some Republicans are politicians, since all senators are politicians.

First, we number the premises and the conclusion: 1. Some senators are Republicans. 2. All senators are politicians. 3. Therefore, some Republicans are politicians. Next, we identify the form of the argument: 1. Some As are Bs. 2. All As are Cs. 3. Therefore, some Bs are Cs. Finally, we try to create a counterexample. First, we might try: 1. Some dogs are animals. (true) 2. All dogs are mammals. (true) 3. Therefore, some animals are mammals. (true) But this won’t work, since the conclusion is true. Next, we might try: 1. Some apples are red. (true) 2. All apples are fruits. (true) 3. Therefore, some red things are fruits. (true) But this won’t work either, since again the conclusion is true. Finally, we might try: 1. Some students love jazz. (true) 2. All students love hot wings. (false)


3. Therefore, some people who love jazz are people who like hot wings. (true) But this fails, too, because not only is the conclusion true, but also one of the premises is false. At this point we might begin to suspect that the reason we can’t find a counterexample is that there is no counterexample to be found, because the blessed thing is valid. And this is in fact the case. One could work until Doomsday trying to come up with a counterexample to the argument in Example 3 and never succeed, since the form of the argument is such that it guarantees a true conclusion if you plug in true premises. And this raises the urgent question: At what point should you throw in the towel? At what point is it safe to conclude that the reason you can’t find a good counterexample to a particular argument is not that you have been insufficiently imaginative or persevering in your attempts, but rather that the argument is simply valid? Alas, there is no such perfect security with the counterexample method. As a rule, however, it’s generally safe to assume after three or four unsuccessful tries that no counterexample can be found. On exams, however, the rule is always: Try as many attempted counterexamples at time permits.

EXERCISE Use the counterexample method to determine whether the following argument forms are valid or invalid. 1. All Albanians are beer-drinkers. Therefore, since all Catalonians are beer-drinkers, all Albanians are Catalonians. 2. If Josef is an anarchist, then he’s a Bolshevik. Hence, Josef is not a Bolshevik, since he’s not an anarchist. 3. No ales are brandies. Some ales are not champagnes. Therefore, some champagnes are not brandies.


4. If Ophelia is an antinomian, then she’s a backslider. Hence, since Ophelia is not a backslider, she’s not an antinomian. 5. Allen is a big spender, since Allen is a Californian, and all Californians are big spenders. 6. If Alice is a Presbyterian, then she believes in God. Hence, Alice is a Presbyterian, since she believes in God. 7. No Argentinians are Bolivians. Therefore, some Cubans are not Bolivians, since some Argentinians are not Cubans. 8. Some animals are brown. Some animals are cows. So, some animals are brown cows. 9. No Alsatians are Burgundians. Some Channel-watchers are not Alsatians. So, some Burgundians are not Channel-watchers. 10. All aphids are bugs. Some aphids are cranky. So, some cranky things are not bugs. 11. No apple-pickers are broncobusters. Some broncobusters are cellists. So, some cellists are apple-pickers. 12. No artichokes are carrots, because no artichokes are beets, and no carrots are beets.

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