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2The Argument

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Learning Objectives After reading this chapter, you should be able to:

1. Articulate a clear definition of logical argument.

2. Name premise and conclusion indicators.

3. Extract an argument in the standard form from a speech or essay with the aid of paraphrasing.

4. Diagram an argument.

5. Identify two kinds of arguments—deductive and inductive.

6. Distinguish an argument from an explanation.

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Section 2.1 Arguments in Logic

Chapter 1 defined logic as the study of arguments that provides us with the tools for arriving at warranted judgments. The concept of argument is indeed central to this definition. In this chapter, then, our focus shall be entirely on defining arguments—what they are, how their component parts function, and how learning about arguments helps us lead better lives. Most especially, in this chapter we will introduce the standard argument form, which is the struc- ture that helps us identify arguments and distinguish good ones from bad ones.

2.1 Arguments in Logic Chapter 1 provisionally defined argument as a methodical defense of a position. We referred to this as the commonsense understanding of the way the word argument is employed in logic. The commonsense definition is very useful in helping us recognize a unique form of expression in ordinary human communication. It is part of the human condition to differ in opinion with another person and, in response, to attempt to change that person’s opinion. We may attempt, for example, to provide good reasons for seeing a particular movie or to show that our preferred kind of music is the best. Or we may try to show others that smoking or heavy drinking is harmful. As you will see, these are all arguments in the commonsense understanding of the term.

In Chapter 1 we also distinguished the commonsense understanding of argument from the meaning of argument in ordinary use. Arguments in ordinary use require an exchange between at least two people. As clarified in Chapter 1, commonsense arguments do not neces- sarily involve a dialogue and therefore do not involve an exchange. In fact, one could develop a methodical defense of a position—that is, a commonsense argument—in solitude, simply to examine what it would require to advocate for a particular position. In contrast, arguments, as understood in ordinary use, are characterized by verbal disputes between two or more people and often contain emotional outbursts. Commonsense arguments are not character- ized by emotional outbursts, since unbridled emotions present an enormous handicap for the development of a methodical defense of a position.

In logic an argument is a set of claims in which some, called the premises, serve as support for another claim, called the conclusion. The conclusion is the argument’s main claim. For the most part, this technical definition of argument is what we shall employ in the remainder of this book, though we may use the commonsense definition when talking about less technical examples. Table 2.1 should help clarify which meanings are acceptable within logic. Take a moment to review the table and fix these definitions in your mind.

Table 2.1: Comparing meanings for the term argument

Meaning in ordinary use Commonsense meaning Technical meaning in logic

A verbal quarrel or disagree- ment, often characterized by raised voices and flaring emotions.

The methodical and well- researched defense of a position or point of view advanced in relation to a disputed issue.

A set of claims in which some, called premises, serve as support for another claim, called the conclusion.

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Section 2.1 Arguments in Logic

Arguments in the technical sense are a primary way in which we can defend a position. Accordingly, we can find the structure of logical arguments in commonsense arguments all around us: in letters to the editor, social media, speeches, advertisements, sales pitches, pro- posals submitted for grant funds or bank loans, job applications, requests for a raise, commu- nications of values to children, marriage proposals, and so on. Arguments often provide the basis on which most of our decisions are made. We read or hear an argument, and if we are convinced by it, then we accept its conclusion. For example, consider the following argument:

“I’m just not a math person.” We hear this all the time from anyone who found high school math challenging. . . . In high school math at least, inborn talent is less important than hard work, preparation, and self-confidence. This is what high school math teachers, college professors, and private tutors have observed as the pattern of those who become good in high school math. They point out that in any given class, students fall in a wide range of levels of math preparation. This is not due to genetic predisposition. What is rarely observed is that some children come from households in which parents introduce them to math early on and encourage them to practice it. These students will imme- diately obtain perfect scores while the rest do not. As a result, the students without previous preparation in math immediately assume that those with perfect scores have a natural math talent, without knowing about the prepa- ration that these students had in their homes. In turn, the students who obtain perfect scores assume that they have a natural math talent given their scores relative to the rest of the class, so they are motivated to continue honing their math skills and, by doing this, they cement their top of the class standing. Thus, the belief that math ability cannot change becomes a self-fulfilling prophecy. (Kimball & Smith, 2013)

In this argument, the position defended by the authors is that the belief that math ability can- not change becomes a self-fulfilling prophecy. The authors support this claim with reasons that show good performance in math is not typically the result of a natural ability but of hav- ing a family support system for learning, a prior preparation in math from home, and continu- ous practice. It makes the case that it is hard work and preparation that lead to a person’s proficiency in math and other subjects, not genetic predisposition. This argument helps us recognize that we frequently accept oft-repeated information as fact without even question- ing the basis. As you can see, an argument such as this can provide a solid basis for our every- day decisions, such as encouraging our children to work hard and practice in the subjects they find most difficult or deciding to obtain a university degree with confidence later in life.

To understand the more technical definition of an argument as a set of premises that support a conclusion, consider the following presentation of the reasoning from the commonsense argument we have just examined.

Good performance in math is not due to genetics.

Good performance in math only requires preparation and continuous practice.

Students who do well initially assume they have natural talent and practice more.

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Section 2.1 Arguments in Logic

Students who do less well initially assume they do not have natural talent and practice less.

Therefore, believing that one’s math ability cannot change becomes a self- fulfilling prophecy.

Presenting the reasoning this way can do a great deal to clarify the argument and allow us to examine its central claims and reasoning. This is why the field of logic adopts the more techni- cal definition of argument for much of its work.

Regardless of what we think about math, an important contribution of this argument is that it makes the case that it is hard work and preparation that lead to our proficiency in math, and not the factor of genetic predisposition. Logic is much the same way. If you find some concepts difficult, don’t assume that you just lack talent and that you aren’t a “logic person.” With prac- tice and persistence, anyone can be a logic person.

On your way to becoming a logic person, it is important to remember that not everything that presents a point of view is an argument (see Table 2.2 for examples of arguments and nonar- guments). Consider that when one expresses a complaint, command, or explanation, one is indeed expressing a point of view. However, none of these amount to an argument.

Table 2.2: Is it an argument?

Argument Not an argument

Reprinted with permission from The Hill Times.

Why? This presents a defense of a position. But not all letters to the editor contain arguments.

©Bettmann/Corbis

Why not? This only reports a news story. It informs us of the role of the university but does not offer a defense of a position.

(continued)

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Section 2.1 Arguments in Logic

Argument Not an argument

Greg Gibson/Associated Press

Why? This is a photo of former president Bill Clin- ton making a speech, in which he defends his posi- tion that the facts are different than those reported by the media. Not all speeches contain arguments, only those that defend a position.

©MIKE SEGAR/Reuters/Corbis

Why not? This is a debate between two presidential candidates. Although each candidate may present various arguments, the debate as a whole is not an argument. It is not a defense of a position; it is an exchange between two people on various subjects.

Emmanuel Dunand/AFP/Getty Images

Why? This ad makes a claim and offers a reason for why viewers should take notice.

©James Lawrence/Transtock/Corbis

Why not? This ad has no words, so it makes no specific claim. Even if we try to interpret it to make a claim, no defense is offered.

To help us properly identify logical arguments, we need clear criteria for what a logical argu- ment is. Let us start unpacking what is involved in arguments by addressing their smallest element: the claim.

Claims A claim is an assertion that something is or is not the case. Claims take the form of declara- tive sentences. It is important to note that each premise or conclusion consists of one single claim. In other words, each premise or conclusion consists of one single declarative sentence.

Claims can be either true or false. This means that if what is asserted is actually the case, then the claim is true. If the claim does not correspond to what is actually the case, then the claim is false. For example, the claim “milk is in the refrigerator” predicates that the subject of the

Table 2.2: Is it an argument? (continued)

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Section 2.1 Arguments in Logic

claim, milk, is in the refrigerator. If this claim corresponds to the facts (if the refrigerator con- tains milk), then this claim is true. If it does not correspond to the facts (if the refrigerator does not contain milk), then the claim is false.

Not all claims, however, can be easily checked for truth or falsity. For exam- ple, the truth of the claim “Jacob has the best wife in the world” cannot be settled easily, even if Jacob is the one asserting this claim (“I have the best wife in the world”). In order to under- stand what he could possibly mean by “best wife in the world,” we would have to propose the criteria for what makes a good wife in the first place, and as if this were not challenging enough, we would then have to establish a method or procedure to make comparisons among good wives. Of course, Jacob could merely mean “I like being mar- ried to my wife,” in which case he is not stating a claim about his wife being the

best in the world but merely stating a feeling. It is not uncommon to hear people state things that sound like claims but are actually just expressions of preference or affection, and distin- guishing between these is often challenging because we are not always clear in the way we employ language. Nonetheless, it is important to note that we often make claims from a par- ticular point of view, and these claims are different from factual claims. Claims that advance a point of view, such as the example of Jacob’s wife—and especially claims about morality and ethicality—are indeed more challenging to settle as true or false than factual claims, such as “The speed limit here is 55.”

The important point is that both kinds of claims—the factual claim and the point-of-view claim—assert that something is or is not the case, affirm or deny a particular predicate of a subject, and can be either true or false. The following sentences are examples of claims that meet these criteria.

• There is a full moon tonight. • Pecans are better than peanuts. • All flights to Paris are full. • BMWs are expensive to maintain. • Lola is my sister.

The following are not claims:

• Is it raining? Why? Because questions are not, and cannot be, assertions that some- thing is the case.

• Oh, to be in Paris in the springtime! Why? Because this expresses a sentiment but does not state that anything might be true or false.

• Buy a BMW! Why? Because a command is not an assertion that something is the case.

Image Source Pink/Image Source/Thinkstock

What factual claims can you make about this image?

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Section 2.1 Arguments in Logic

We often intend to advance claims in ways that do not present our claims clearly and properly— for example, by means of rhetorical questions, vague expressions of affection, and commands or metaphors that demand interpretation. But it is important to recognize that intention is not sufficient when communicating with others. In order for our intended claims to be identified as claims, they should meet the three criteria previously mentioned.

Claims are sometimes called propositions. We will use the terms claims and propositions inter- changeably in this book. In this chapter we will stick to the word claim, but in subsequent chapters, we will move to the more formal terminology of propositions.

The Standard Argument Form In informal logic the main method for identifying, constructing, or examining arguments is to extract what we hear or read as arguments and put this in what is known as the standard argument form. It consists of claims, some of which are called premises and one of which is called the conclusion. In the standard argument form, premises are listed first, each on a separate line, with the conclusion on the line after the last premise. There are various meth- ods for displaying standard form. Some methods number the premises; others separate the conclusion with a line. We will generally use the following method, prefacing the conclusion with the word therefore:

Premise Premise Therefore, Conclusion

The number of premises can be as few as one and as many as needed. We must approach either extreme with caution given that, on the one hand, a single premise can offer only very limited support for the conclusion, and on the other hand, many premises risk error or confu- sion. However, there are certain kinds of arguments that, because of their formal structure, may contain only a limited number of premises.

In the standard argument form, each premise or conclusion should be only one sentence long, and premises and conclusions should be stated as clearly and briefly as possible. Accordingly, we must avoid premises or conclusions that have multiple sentences or single sentences with multiple claims. The following example shows what not to do:

I live in Boston, and I like clam chowder. My family also lives in Boston. They also like clam chowder. My friends live in Boston. They all like clam chowder, too. Therefore, everyone I know in Boston likes clam chowder.

If you want to make more than one claim about the same subject, then you can break your declarative sentences into several sentences that each contain only one claim. The clam chow- der argument can then be rewritten as follows:

I live in Boston. I like clam chowder. My family lives in Boston. My family likes clam chowder.

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Section 2.1 Arguments in Logic

My friends live in Boston. My friends like clam chowder. Therefore, everyone I know in Boston likes clam chowder.

The relationship between premises and the conclusion is that of inference—the process of drawing a claim (the conclusion) from the reasons offered in the premises. The act of reason- ing from the premises serves as the glue connecting the premises with the conclusion.

Practice Problems 2.1

Determine whether the following sentences are claims (propositions) or nonclaims (nonpropositions).

1. Moby Dick is a great novel.

2. Computers have made our lives easier.

3. If we go to the movies, we will need to drive the minivan.

4. Do you want to drive the minivan to the movies?

5. Drive the minivan.

6. Either I am a human or I am a dog.

7. Michael Jordan was a great football player.

8. Was it time for you to leave?

9. Private property is a right of every American.

10. Universalized health care is communism.

11. Don’t you dare vote for universalized health care.

12. Nietzsche collapsed in a square upon seeing a man beat a horse.

13. Hooray!

14. Those who reject equality seek tyranny.

15. How many feet are in a mile?

16. If you cannot understand the truth value of a claim, then it is not a claim.

17. Something is a claim if and only if it has a truth value.

18. Treat your boss with respect.

19. Men are much less likely to have osteoporosis than women are.

20. Why are women less likely to have heart attacks?

21. Do as we say.

22. I believe that you should do as your parents say.

23. Socrates is mortal. (continued)

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Section 2.2 Putting Arguments in the Standard Form

24. Why did Freud hold such strange beliefs about parent–child relationships?

25. A democracy exists if and only if its citizens participate in autonomous elections.

26. Do your best.

27. The unexamined life is not worth living.

28. Ayn Rand believed that selfishness was a virtue.

29. Is selfishness a virtue?

30. What people love is not the object of desire, but desire itself.

31. Hey!

32. Those who cannot support themselves should not be supported by taxpayer dollars.

33. Particle and wave behavior are properties of light.

34. Why do we feed so many pounds of plants to animals each year?

35. Go and give your brother a kiss.

36. Because the mind conditions reality, it is impossible to know the thing as such.

37. The library at the local university has more than 300,000 books.

38. Does the nature of reality consist of an ultimately creative impulse?

39. You are taking a quiz.

40. Are you taking a quiz?

Practice Problems 2.1 (continued)

2.2 Putting Arguments in the Standard Form Presenting arguments in the standard argument form is crucial because it provides us with a dispassionate method that will allow us to find out whether the argument is good, regardless of how we feel about the subject matter. The first step is to identify the fundamental argument being presented.

At first it might seem a bit daunting to identify an argument, because arguments typically do not come neatly presented in the standard argument form. Instead, they may come in confus- ing and unclear language, much like this statement by Special Prosecutor Francis Schmitz of Wisconsin regarding Governor Scott Walker:

Governor Walker was not a target of the investigation. At no time has he been served with a subpoena. . . . While these documents outlined the prosecutor’s legal theory, they did not establish the existence of a crime; rather, they were arguments in support of further investigation to determine if criminal charges against any person or entity are warranted. (Crocker, 2014, para. 7 & 10)

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Section 2.2 Putting Arguments in the Standard Form

This was a position presented in regard to the investigation of an alleged illegal campaign finance coordination during the 2011–2012 recall elections (Stein, 2014). Does it claim a vin- dication of Walker? Or does it suggest that there may be sufficient evidence to make Walker a central figure in the investigation? How would you even begin to make heads or tails of such a confusing argument? Do not despair. The remainder of this section will show you exactly what to look for in order to make sense of the most complicated argument. With a little prac- tice, you will be able to do this without much effort.

Find the Conclusion First Although the conclusion is last in the standard form, the conclusion is the first thing to find because the conclu- sion is the main claim in an argument. The other claims—the premises—are present for the sole purpose of support- ing the conclusion. Accordingly, if you are able to find the conclusion, then you should be able to find the premises.

The good news is that language is not only a means for expressing ideas; it also offers a road map for the ideas presented. Chapter 1 underscored the fundamental importance of clear, pre- cise, and correct language in logical reasoning. When used properly, lan- guage also offers structures and direc- tions for communicating meaning, thus facilitating our understanding of what others are saying. One punctua- tion mark—the question mark—tells us that we are confronting a question. A different punctuation mark—the parentheses—tells us that we are being given relevant information but only as an aside or afterthought to the main point; if removed, the parenthetical information would not alter the main point. In the case of arguments, some words serve as signposts identifying conclusions. Take the following example of an argument in the standard argument form:

All men are mortal. Socrates is a man. Therefore, Socrates is mortal.

The word therefore indicates that the sentence is a conclusion. In fact, the word therefore is the standard conclusion indicator we will use when constructing arguments in the stan- dard argument form. However, there are other conclusion indicators that are used in ordinary arguments, including:

• Consequently . . . • So . . . • Hence . . . • Thus . . .

Xtock Images/iStock/Thinkstock

Punctuation, parentheses, and conclusion indicators all serve as signposts to assist us when deconstructing an argument. They provide important clues about where to find the conclusion as well as supporting claims.

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Section 2.2 Putting Arguments in the Standard Form

• Wherefore . . . • As a result . . . • It follows that . . . • For these reasons . . . • We may conclude that . . .

When a conclusion indicator is present, it can help identify the conclusion in an argument. Unfortunately, many arguments do not come with conclusion indicators. In such cases start by trying to identify the main point. If you can clearly identify a single main point, then that is likely to be the conclusion. But sometimes you will have to look at a passage closely to find the conclusion. Suppose you encounter the following argument:

Don’t you know that driving without a seat belt is dangerous? Statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one. Besides, in our state you can get fined $100 if you are caught not wearing one. You ought to wear one even if you are driving a short distance.

Arguments are often longer and more complicated than this one, but let us work with this simple case before trying more complicated examples. You know that the first thing you need to do is to look for the conclusion. The problem is that the author of the argument does not use a conclusion indicator. Now what? Nothing to worry about. Just remember that the con- clusion is the main claim, so the thing to look for is what the author may be trying to defend. Although the first sentence is stated as a question—remember, punctuation marks give us important clues—the author seems to intend to assert that driving without a seat belt is dan- gerous. In fact, the second sentence offers evidence in support of this claim. On the other hand, the third sentence seems to be important, yet it does not speak to driving without a seat belt being dangerous, only expensive. In the final sentence, we find a claim that is supported by all the others. Because of this, the final sentence presents the conclusion.

Now, it so happens that in this case, the conclusion is at the end of this short argument, but keep in mind that conclusions can be found in various places in essays, such as the beginning or sometimes in the middle. Now that you have identified your first piece of the puzzle, we have this:

Premise 1: ? Premise 2: ? Premise 3: ? Therefore, you ought to wear a seat belt whenever you drive.

You might have noticed that the conclusion does not appear as it did in the essay. The origi- nal sentence is “You ought to wear one even if you are driving a short distance.” Why did we modify it? Once again, clarity is of the essence in logical reasoning. Conclusions should make the subject clear, so the pronoun one was replaced with the actual subject to which the author is referring: seat belt. In addition, the predicate “even if you are driving a short distance” was rewritten to reflect the more inclusive point that the author seems to be making: that you should wear a seat belt whenever you drive.

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Section 2.2 Putting Arguments in the Standard Form

This modification of language, known as paraphrasing, is part of the construction of argu- ments in the standard argument form. The act of extracting an argument from a longer piece to its fundamental claims in the standard argument form necessarily involves paraphrasing the original language to the clearest and most precise form possible. This concept will be addressed in greater detail later in this section.

Find the Premises Next After identifying the conclusion, the next thing to do is look for the reasons the author offers in defense of his or her position. These are the premises. As with conclusions, there are prem- ise indicators that serve as signposts that reasons are being offered for the main claim or conclusion. Some examples of premise indicators are:

• Since . . . • For . . . • Given that . . . • Because . . . • As . . . • Owing to . . . • Seeing that . . . • May be inferred from . . .

To practice identifying premises, let us return to our seat belt example:

Notice again that this argument starts with a question: “Don’t you know that driving without a seat belt is danger- ous?” The author is not really asking whether you know that driving with- out a seat belt is dangerous. Rather, the author seems to be asking a rhe- torical question—a question that does not actually demand an answer—to assert that driving without a seat belt is dangerous. You should avoid asking rhetorical questions in the essays that you write, because the outcome can be highly uncertain. The success of a rhe- torical question depends on the reader or listener first understanding the hid- den meaning behind the rhetorical question and then correctly articulat- ing the answer you have in mind. This does not always work.

Hkeita/iStock/Thinkstock

Much like a map will get you from point A to point B, putting an argument into the standard argument form will help you navigate from the conclusion to the premises and vice versa.

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Section 2.2 Putting Arguments in the Standard Form

For the sake of this example, however, let us do our best to try to get at the author’s inten- tion. We could paraphrase the first premise to the following claim: Driving without a seat belt is dangerous. Does this paraphrased claim serve as a premise in support of the conclu- sion? In order to answer this, we need to put the conclusion in the form of a question. Again, premises are reasons offered in support of the conclusion, so if we have a well-constructed argument, then the premises should answer why the conclusion is the case. This is what we would have:

Question: Why must you wear a seat belt whenever you drive?

Answer: Because driving without a seat belt is dangerous.

This works, so the paraphrased claim that we drew from the author’s rhetorical question is indeed a reason in defense of the conclusion. So now we have one more piece of the puzzle:

Premise 1: Driving without a seat belt is dangerous. Premise 2: ? Premise 3: ? Therefore, you ought to wear a seat belt whenever you drive.

Let us now move to the next sentence: “Statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one.” Is this a claim that can be a support for the conclusion? In other words, if we put the conclusion in the form of a question again as we did before, would this sentence be an adequate reason in response? Let us see.

Question: Why must you wear a seat belt whenever you drive?

Answer: Because statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one.

The answer provides a reason in support of the conclusion, and thus, we have another prem- ise. Now we have most of the puzzle completed, as follows:

Premise 1: Driving without a seat belt is dangerous. Premise 2: Statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one. Premise 3: ? Therefore, you ought to wear a seat belt whenever you drive.

We have one more sentence left in the argument, which reads: “Besides, in our state you can get fined $100 if you are caught not wearing one.” Is this a premise? Well, it is uncer- tain, since the sentence is not presented in the form of a claim. So let us paraphrase it as a claim as follows: “Not wearing a seat belt can result in a $100 fine.” This is now a claim, and the paraphrasing has not altered the meaning, so we can proceed to our question: Is this a

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Section 2.2 Putting Arguments in the Standard Form

premise for the argument that we are examining? Once again, let us put the conclusion into a question:

Question: Why must you wear a seat belt whenever you drive?

Answer: Because not wearing a seat belt can result in a $100 fine.

This is a claim that can be a support for the conclusion, and thus, we have another premise. We can now see the argument presented more formally as follows:

Driving without a seat belt is dangerous. Statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one. Not wearing a seat belt can result in a $100 fine. Therefore, you ought to wear a seat belt whenever you drive.

The Necessity of Paraphrasing As we have discussed, extracting the fundamental claims from a written or a spoken argument often involves paraphrasing. Paraphrasing is not merely an option but rather a necessity in order to uncover the intended argument in the best way possible. Most other arguments presented to you (especially those in the media) will not consist of only premises and the conclusion in clearly identifiable language. Furthermore, many arguments will be much longer and compli- cated than the seat belt argument example. Often, arguments are presented with many other sentences that do not serve the purposes of an argument, such as empty rhetorical devices, filler sentences that aim to manipulate your emotions, and so on. So your task in extracting an argument from such sources is akin to that of a surgeon—removing all those linguistic tumors that obscure the argument in order to reveal the basic claims presented and their supporting evidence. In other words, you should expect to do paraphrasing as a necessary task when you attempt to draw an argument in the standard form from almost any source.

It is important to recognize that not everyone who advances an argument does so clearly or even coherently. This is precisely why the structure of the standard argument form is such a powerful tool to command. It offers you the machinery to distinguish arguments from what are not arguments. It also helps you unearth the elements of an argument that are buried under complicated prose and rhetoric. And it helps you evaluate the worthiness of the argument presented once it has been fully clarified. You should paraphrase all claims when presenting them in the standard argument form, whether the claims are implied in a long argumentative essay or speech or in shorter arguments that may be ambiguous or unclear. (To understand the added benefits, see Everyday Logic: Modesty and Charity.)

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Section 2.2 Putting Arguments in the Standard Form

Thinking Analytically Identifying an argument’s components as we have just done is an example of analytical think- ing. When we analyze something, we examine its architectural structure—that is, the relation of the whole to its parts—to identify its parts and to see how the parts fit together as a whole.

Let us examine an excerpt from President Barack Obama’s (2014) speech on Ebola as a way of bringing the new skills from this section all together:

Everyday Logic: Modesty and Charity

The goal of paraphrasing is to find the best presentation of the premises and conclusions intended. By presenting the argument offered in its best possible light, this will help you see not only how far off the argument is from an optimal defense, but also how good it is despite its bad presentation. Why should you be so charitable?

First we must keep in mind that ideas are important, even if the ideas are not ours. So we must always give our utmost due diligence to the examination of ideas. Sometimes even the roughest presentation of ideas can contain the most impressive pearls of insight. If we are not charitable to the ideas of others, then we might miss out on hidden wisdom.

Second, modesty is a good intellectual habit to develop. It is very easy to fall into the trap of thinking that our thoughts are the best ones around. This is generally far from the truth. The most fruitful innovations of mankind have been quite unexpected, often as the result of someone paying attention to others’ ideas and coming up with a new way of putting them to use. This applies to all sorts of things, including everything from the ways in which cooking methods turned into regional cuisines, to scientific discoveries, product innovations, and the emergence of the Internet.

That modesty has advantages is not a new idea. In the 1980s Peter Drucker wrote the book Inno- vation and Entrepreneurship, in which he recounts, among many other stories, the story of how Ray Kroc founded the burger chain McDonald’s®. As the well-known story goes, Kroc bought a hamburger stand from the McDonald brothers, along with their invention of a milkshake machine. Although Kroc never invented anything, his entrepreneurial genius was in seeing the potential of a hamburger, fries, and milkshake business that catered to mothers with little chil- dren and turning this vision into a billion-dollar standardized operation (Drucker, 1985/2007).

Even if you dislike McDonald’s, the point is that Kroc noticed the potential for something that many, including the McDonald brothers themselves, had overlooked. Gems are everywhere in the world of ideas, but we often have to dust them off, remove all the excess baggage, and extract what is good in them. Intellectual modesty allows us to do this; we don’t blind our- selves by assuming our own ideas are best. Once we seek to fully understand others’ ideas and allow them to challenge our own, we can do all sorts of good things: understand an idea more clearly, understand someone better, and understand ourselves (our values, what we find important, and so on) better as well.

Given that our human social world is characterized by diversity of ideas, modesty also marks the path of cooperation, harmony, and respect among human beings. This is one of the many small ways in which the application of logical reasoning can help us all have better lives and better relations with other people. If we could all use logical reasoning on a regular basis, per- haps we would not have as many wars and atrocities as we have today.

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Section 2.2 Putting Arguments in the Standard Form

In West Africa, Ebola is now an epidemic of the likes that we have not seen before. It’s spiraling out of control. It is getting worse. It’s spreading faster and exponentially. Today, thousands of people in West Africa are infected. That num- ber could rapidly grow to tens of thousands. And if the outbreak is not stopped now, we could be looking at hundreds of thousands of people infected, with pro- found political and economic and security implications for all of us. So this is an epidemic that is not just a threat to regional security—it’s a potential threat to global security if these countries break down, if their economies break down, if people panic. That has profound effects on all of us, even if we are not directly contracting the disease. (para. 8)

We have identified “The West African Ebola epidemic is a potential threat to global security” as the conclusion. What are the premises? Read the passage a few times while asking yourself, “Why should I think the epidemic is a global threat?” Obama says that the epidemic is not like others, that it is growing faster and exponentially. He moves from there being thousands of people infected, to tens of thousands, to the possibility of hundreds of thousands. So far, everything is about how fast the epidemic is growing.

In the middle of the seventh sentence, the president switches from talking about the growth of the epidemic to claiming that it has profound economic and security implications. What is the basis for the claim that the growth will have these effects? Notice that it is not in the seventh sentence, at least not explicitly. However, the last part of the eighth sentence does address this. In that sentence, Obama suggests three conditions that might lead to a global security threat: “if these countries break down, if their economies break down, if people panic.” So the extreme growth of the epidemic may lead to the breakdown of economies or countries, or it may lead to widespread panic. If any of these things happen, there are “profound effects on all of us.” Therefore, the epidemic is a potential threat to global security. We can now list the premises, and indeed the entire argument, in standard form as follows:

The West African Ebola epidemic is growing extremely fast. If the growth isn’t stopped, the countries may break down. If the growth isn’t stopped, the economies may break down. If the growth isn’t stopped, people may panic. Any of these things would have profound effects on people outside of the region. Therefore, the West African Ebola epidemic is a potential threat to global security.

Notice that putting the argument in standard form may lose some of the fluidity of the origi- nal, but it more than makes up for it in increased clarity.

Practice Problems 2.2

Identify the premises and conclusions in the following arguments.

1. Every time I turn on the radio, all I hear is vulgar language about sex, violence, and drugs. Whether it’s rock and roll or rap, it’s all the same. The trend toward vulgarity has to change. If it doesn’t, younger children will begin speaking in these ways, and this will spoil their innocence.

2. Letting your kids play around on the Internet all day is like dropping them off in downtown Chicago to spend the day by themselves. They will find something that gets them into trouble.

(continued)

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Section 2.2 Putting Arguments in the Standard Form

3. Too many intravenous drug users continue to risk their lives by sharing dirty nee- dles. This situation could be changed if we were to supply drug addicts with a way to get clean needles. This would lower the rate of AIDS in this high-risk population as well as allow for the opportunity to educate and attempt to aid those who are addicted to heroin and other intravenous drugs.

4. I know that Stephen has a lot of money. His parents drive a Mercedes. His dogs wear cashmere sweaters, and he paid cash for his Hummer.

5. Dogs are better than cats, since they always listen to what their masters say. They also are more fun and energetic.

6. All dogs are warm-blooded. All warm-blooded creatures are mammals. Hence, all dogs are mammals.

7. Chances are that I will not be able to get in to see Slipknot since it is an over-21 show, and Jeffrey, James, and Sloan were all carded when they tried to get in to the club.

8. This is not the best of all possible worlds, because the best of all possible worlds would not contain suffering, and this world contains much suffering.

9. Some apples are not bananas. Some bananas are things that are yellow. Therefore, some things that are yellow are not apples.

10. Since all philosophers are seekers of truth, it follows that no evil human is a seeker after truth, since no philosophers are evil humans.

11. All squares are triangles, and all triangles are rectangles. So all squares are rectangles.

12. Deciduous trees are trees that shed their leaves. Maple trees are deciduous trees. Thus, maple trees will shed their leaves at some point during the growing season.

13. Joe must make a lot of money teaching philosophy, since most philosophy professors are rich.

14. Since all mammals are cold-blooded, and all cold-blooded creatures are aquatic, all mammals must be aquatic.

15. If you drive too fast, you will get into an accident. If you get into an accident, your insurance premiums will increase. Therefore, if you drive too fast, your insurance premiums will increase.

16. The economy continues to descend into chaos. The stock market still moves down after it makes progress forward, and unemployment still hovers around 10%. It is going to be a while before things get better in the United States.

17. Football is the best sport. The athletes are amazing, and it is extremely complex.

18. We should go to see Avatar tonight. I hear that it has amazing special effects.

19. All doctors are people who are committed to enhancing the health of their patients. No people who purposely harm others can consider themselves to be doctors. It fol- lows that some people who harm others do not enhance the health of their patients.

20. Guns are necessary. Guns protect people. They give people confidence that they can defend themselves. Guns also ensure that the government will not be able to take over its citizenry.

Practice Problems 2.2 (continued)

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There’s snow on the ground.

It’s cold outside.

Section 2.3 Representing Arguments Graphically

2.3 Representing Arguments Graphically In the preceding section, we discussed the component parts of an argument and how we can identify each when we encounter them in writing. Although the standard argument form is useful and will be used throughout this book, you may find it easier to display the structure of an argument by drawing the connections between the parts of an argument. We will start by learning some simple techniques for diagramming arguments. An argument diagram (also called an argument map) is just a drawing that shows how the various pieces of an argument are related to each other.

Representing Reasons That Support a Conclusion The simplest argument consists of two claims, one of which supports the other—which means that one is the premise and the other is the conclusion. For example:

There is snow on the ground, so it must be cold outside.

To represent this argument, we put each claim in a box and draw an arrow to show which one supports the other. We can diagram this argument in the following way:

Notice that the claims are represented by simple, complete sentences. The premise is at the start of the arrow, and the conclusion is at the end. The arrow represents the process of inferring the conclusion from the premise. Seeing snow on the ground is indeed a reason for believing that it is cold.

But arguments can be more complex. First, consider that an argument may have more than one line of support. For example:

There’s snow on the ground.

It’s cold outside.

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There’s snow on the ground.

It’s February in Idaho.

It’s cold outside.

It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

It’s cold outside.

Section 2.3 Representing Arguments Graphically

The important thing here is that the two lines of support are independent of each other. Knowing that it is February in Idaho is a reason for thinking that it is cold outside, even if you do not see snow. Similarly, seeing snow outside is a reason for thinking it is cold regardless of when or where you see it.

Second, it can also be the case that a single line of support contains multiple premises that work together. For example, although February in Idaho offers good grounds for thinking it is cold outside, this reason is strengthened if it also happens to be a particularly cold year. A year being particularly cold is not by itself much of a reason to think it is cold outside. Even a cold year will be warm in the summer. But a February day in a cold year is even more likely to be cold than a February day in a warm one. We represent this by starting the arrow at a group of premises (bottom):

It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

It’s cold outside.

There’s snow on the ground.

It’s February in Idaho.

It’s cold outside.

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It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

John came in with snow on his boots.

It’s cold outside.

Section 2.3 Representing Arguments Graphically

Although arrows can sometimes start at a group of claims, they always end at a single claim. This is because every simple argument or inference has only one conclusion, no matter how many premises it may have.

Finally, arguments can form chains with some claims being used as a conclusion for one infer- ence and a premise for another. For example, if your reason for thinking that there is snow on the ground is that your friend John just came in with snow on his boots, this can be indicated in a diagram as follows:

Notice that the claim “There is snow on the ground” is a conclusion for one inference and a premise for another. From these basic patterns we can build extremely complicated arguments.

It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

John came in with snow on his boots.

It’s cold outside.

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It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

Most people outside aren’t wearing coats.

John came in with snow on his boots.

It’s cold outside.

Section 2.3 Representing Arguments Graphically

Representing Counterarguments We will discuss one more refinement, and then we will have all of the basic tools we need for constructing argument maps. Sometimes lines of reasoning count against a conclusion rather than support it. If we look out the window and notice that most of the students outside are not wearing coats, that might lead us to believe that it is not very cold even though it is Febru- ary and we see snow. We will represent this sort of contrary argument by using a red arrow with a slash through it:

Just as with supporting lines of reasoning, opposing lines may have multiple premises or chains. From the point of view of logic, these lines of opposing reasoning are not really part of the argument. However, such reasoning is often included when presenting an argument, so it is useful to have a way to represent it. This is especially true when you are trying to under- stand an argument in order to write an essay about it. It is good practice to note what objec- tions an author has already considered so that you do not just repeat them.

It’s February in Idaho.

It’s a very cold year.

There’s snow on the ground.

Most people outside aren’t wearing coats.

John came in with snow on his boots.

It’s cold outside.

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2 1

Section 2.3 Representing Arguments Graphically

With that, you have all the basic tools you need to create argument diagrams. In principle, arguments of any complexity can be represented with diagrams of this sort. In practice, as arguments get more complex, there are many interpretational choices about how to repre- sent them.

Diagramming Efficiently One issue that arises when creating argument diagrams is that including each premise and conclusion can make diagrams large and cumbersome. A common practice is to number each statement in an argument and make the diagram with circled numbers representing each premise and conclusion. See Figure 2.1 for an illustration of the seat belt example from the previous section.

The seat belt example is not a complex argument, but the diagram in Figure 2.1 is able to show how the hidden assertion in the first question is supported by the second statement and how, together with the third assertion, the conclusion is supported. Sketching diagrams that show the relationship among the premises and their connections to the conclusion is very helpful in understanding complex arguments. Yet you must keep in mind that the diagramming is the second stage of the process, since you will have to first identify the ele- ments of the argument.

Figure 2.1: Diagramming the structure of an argument

This diagram shows the relationship between each of the sentences in the seat belt example. Here are the claims: 1. Don’t you know that driving without a seat belt is dangerous? 2. Statistics show that you are 10 times more likely to be injured in an accident if you are not wearing one. 3. Besides, in our state you can get fined $100 if you are caught not wearing one. 4. You ought to wear one even if you are driving a short distance. Notice how numbering the individual components of each argument and diagramming them will help you see the relationship among the pieces and how the pieces work together to support the conclusion.

2 1

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Section 2.4 Classifying Arguments

2.4 Classifying Arguments There are many ways of classifying arguments. In logic, the broadest division is between deductive and inductive arguments. Recall that Section 2.1 introduced the notion of inference, the process of drawing a judgment from the reasons offered in the premises. The distinction between deductive and inductive arguments is based on the strength of that inference. A con- clusion can follow from the premises very tightly or very loosely, and there is a wide range in between. For deductive arguments, the expectation is that the conclusion will follow from the premises necessarily. For inductive arguments, the expectation is that the conclusion will follow from the premises probably but not necessarily. We shall explore these two kinds of arguments in greater depth in subsequent chapters. In this section our goal is to achieve a basic grasp of their respective definitions and understand how the two types differ from one another. Finally, we will improve our understanding of the concept of an argument by com- paring arguments to explanations, which are often mistaken for arguments.

Practice Problems 2.3

Draw an argument map of each of the following arguments, using the described method of numbering each statement and making a diagram with circled numbers representing each premise and conclusion.

1. (1) I know that Stephen has a lot of money. (2) His parents drive a Mercedes. (3) His dogs wear cashmere sweaters, and (4) he paid cash for his Hummer.

2. (1) Guns are necessary. (2) Guns protect people, because (3) they give people con- fidence that they can defend themselves. (4) Guns also ensure that the government will not be able to take over its citizenry.

3. (1) If you drive too fast, you will get into an accident. (2) If you get into an accident, your insurance premiums will increase. Therefore, (3) if you drive too fast, your insurance premiums will increase.

4. Since (1) all philosophers are seekers of truth, it follows that (2) no evil human is a seeker after truth, since (3) no philosophers are evil humans.

5. (1) This cat can experience pain. So (2) it has the right to not suffer. (3) Since we shouldn’t cause suffering, (4) we should not harm the cat.

6. (1) If we change the construction of the conveyer belt, then the timing of the line will change. (2) Thus, if the timing of the line doesn’t change, then we didn’t change the construction of the conveyor belt. (3) In fact, the timing of the line hasn’t changed. (4) So that means we didn’t change the conveyer belt.

7. (1) The affordable health care act is becoming less popular. (2) Cultural sentiment is increasingly negative, and (3) the Senate and House are progressively moving toward opposition to it. (4) Just last week five Democratic senators joined their Republican counterparts to attempt to block certain aspects of the act.

8. (1) Everyone should have to study logic. (2) It is becoming more important to be able to adapt to changes and (3) to evaluate information in today’s workplace. (4) Logic enhances these abilities. (5) Plus, logic helps protect us against manipulators who try to pawn off their fallacious arguments as truth.

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Section 2.4 Classifying Arguments

Deductive Arguments In logic the terms deductive and inductive are used in a technical sense that is somewhat different than the way the terms may be used in other contexts. For example, Sherlock Holmes, the protagonist in Sir Arthur Conan Doyle’s detective novels, often referred to his own style of reasoning as deductive. In fact, the popularity of Sherlock Holmes introduced deductive reasoning into ordinary speech and made it a com- monplace term. Unfortunately, deductive reasoning is often misunderstood, and in the case of Sherlock Holmes, his clever style of reasoning is actually more inductive than deductive. For example, in The Adven- ture of the Cardboard Box, he says:

Let me run over the principal steps. We approached the case, you remember, with an absolutely blank mind, which is always an advantage. We had formed no theories. We were simply there to observe and to draw inferences from our observations. (Doyle, 1892/2008, para. 114)

The foregoing does not describe deductive reasoning as it is employed in logic. In fact, Sher- lock Holmes mostly uses inductive rather than deductive reasoning. For now, the simplest way to present deductive arguments is to say that deductive reasoning is the sort of reasoning that we normally encounter in mathematical proofs. In a mathematical proof, as long as you do not make a mistake, you can count on the conclusion being true. If the conclusion is not true, you have either made an error in the proof or assumed something that was false. The same is true of deductive reasoning, because good deductive arguments are characterized by their truth-preserving nature—if the premises are true, then the conclusion is guaranteed to be true also. Consider the following deductive argument:

All married men are husbands. Jacob is a married man. Therefore, Jacob is a husband.

In this example, the conclusion necessarily follows from the given premises. In other words, if it is true that all married men are husbands and, moreover, that Jacob is a married man, then it must be necessarily true that Jacob is a husband.

But suppose that Jacob is a 3-year-old boy, so he is not a married man. Would the argument still be a good deductive argument and, thereby, truth preserving? The answer is yes, because deductive reasoning reflects the relations between premises and the conclusion such that if it were to be the case that the premises were true, then it would be impossible for the conclu- sion to be false. If it so happens that Jacob is a 3-year-old boy, then the second premise would not be true, and thus, the necessity for the conclusion to be true is broken.

Wiley Miller/Cartoonstock

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Section 2.4 Classifying Arguments

However, this does not mean that all we need are true premises and a true conclusion. Good deductive arguments are not free form; rather, they use specific patterns that must be followed strictly in the inferential operation. Although this might sound rigid, the greatest advantage of good deductive arguments is that their precise structure guides us into grasping a truth that we might not otherwise have recognized with the same certainty. The use of deductive reasoning is quite broad—in science, mathematics, and the examination of moral problems, to name a few examples. Subsequent chapters will demonstrate more about the powerful machinery of deductive arguments.

Inductive Arguments In contrast to deductive arguments, good inductive arguments do not need to be truth pre- serving. Even those that have true premises do not guarantee the truth of their conclusion. At best, true premises in inductive arguments make the conclusion highly probable. The prem- ises of good inductive arguments offer good grounds for accepting the conclusion, but they do not guarantee its truth. Consider the following example:

The produce at my corner store is stocked by local farmers every day. They have a bakery, too, and they refill their shelves with fresh-baked bread twice a day. I have been shopping at my corner store continuously for 5 years, and every day is the same. Therefore, my corner store will have fresh produce and baked goods every day of the week.

Let us suppose that all the premises are true. After 5 years of going to the corner store and getting to know its practices and the quality of its daily offerings, the conclusion would seem to be highly probable. But is it necessarily true? At some point the store may change hands, close, or experience something else that interrupts its normal operations. Such cases show that even though the reasoning is good, the conclusion is not guaranteed to be true just because the premises are true.

Another way to think of what is going on here is to address a likely familiar fact of the human condition: Past experience does not guarantee that the future will be the same. Think of that great car you loved that did not require any expensive maintenance—and then suddenly one day it started to break down bit by bit with age. Time changes the performance of things. Or think of the great quality of a clothing brand you counted on year after year that one day was no longer as good. Products also change with time as the leaders of the manufacturing company change or the standards become somewhat relaxed. Things change. Sometimes the changes are for the better, sometimes for the worse. But our observation of how things are now and have been in the past does not guarantee that things will remain the same in the future. Accordingly, even if the conclusion in our corner store example seems sufficiently jus- tified for us to venture saying that it is true, the fact is that at some point it could change. At best, we can say that the premises give us good grounds to assert that it is probably true that the store will have good produce and baked goods this coming week.

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Section 2.4 Classifying Arguments

Despite having a weaker connection between premises and conclusion, inductive arguments are more widely used than deductive arguments. In fact, you have likely been using inductive reasoning your entire life without knowing it. Think about the expectation you have that your car, house, or other object will be in the location you last left it. This expectation is based on good inductive reasoning. You have good reasons for expecting your car to be sitting in the parking space where you left it. We can represent your reasoning as follows:

I left my car in that spot. I have always found my car in the same parking spot I left it in. Therefore, my car will be in that spot when I return.

Of course, having good reason is not the same as having a guarantee, as anyone who has expe- rienced having their vehicle stolen can attest. This is the difference between deductive and inductive arguments. Because inductive arguments only establish that their conclusions are probable, the conclusions can turn out to be false even when the premises are all true. The chance may be small, but there is always a chance. By contrast, a good deductive argument is airtight; it is absolutely impossible for the conclusion to be false when the premises are true. Of course, if one of the premises is false, then neither kind of argument can establish its con- clusion. If you misremember which spot you parked in, then you are not likely to find your car immediately, even if it is right where you left it.

Arguments Versus Explanations Mastering logical reasoning requires not only understanding what arguments are, but also being able to distinguish arguments from their closest conceptual neighbors. Although it might be clear by now why news articles, debates, and commands are not considered argu- ments, we should take a closer look at explanations, because they are commonly mistaken for arguments and present a similar framework. Arguments provide a methodical defense of a position, presenting evidence by means of premises in support of a conclusion that is dis- puted. Explanations, in contrast, tell why or how something is the case.

Suppose that we have the following claim:

We have to travel by train instead of by plane.

If you disagree with this decision, then you might question this claim, thus presenting a request for evidence. Accordingly, an argument would be the appropriate response. We could then have the following:

The total cost for plane tickets is $2,000. The total cost for train tickets is $1,000. We have a budget of $1,200 for this trip. Therefore, we have to travel by train instead of by plane.

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Section 2.4 Classifying Arguments

Now, suppose that you do not question the claim, but you still want to know why we have to travel by train. This is not a request for evidence for the conclusion. Rather, this is a request for the cause that leads to the conclusion. This is thus a request for an explanation, which may be as simple as this:

Because we do not have enough money for plane tickets.

The point of an argument is to establish its main claim as true. The point of an explanation is to say how or why its main claim is true. In arguments, the premises will likely be less controver- sial than the conclusion. It is difficult to convince someone that your conclusion is true if they are even less likely to agree with your premises. In explanations, the thing being explained is likely to be less controversial than the explanation given. There is little reason to explain why or how something is true if the listener does not already accept that it is true. Unlike argu- ments, then, explanations do not involve contested conclusions but, instead, accepted ones. Their point is to say why or how the primary claim is true, not to provide reasons for believing that it is true. This explanation might be fairly straightforward, but distinguishing between arguments and explanations in real life may seem a bit more blurry.

As an example, suppose you try to start your car one morning and it will not start. You recall that your son drove the car last night and know that he has a bad habit of leaving the lights on. You see the light switch is on. You now understand why the car will not start. In our scenario, you found out your car would not start and then looked around for the reason. After noticing that the light switch was on, you came up with the following explanation:

Your son left the lights on. Leaving the lights on will drain the battery. A drained battery will prevent the car from starting. That’s why your car won’t start.

It is an explanation because you already know that your car will not start; you just want to know why.

On the other hand, suppose that after your son got home last night, you noticed that he left the lights on. Rather than turn them off or tell him to do it, you decide to teach him a lesson by let- ting the battery go dead. In the morning you have the following conversation with your son:

You: I hope you don’t need to go anywhere with the car this morning.

Son: Why?

You: You left the car’s lights on last night.

Son: So?

You: The lights will have completely drained the battery. The car won’t start with a dead battery, so it’s not going to start this morning.

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Section 2.4 Classifying Arguments

In this case the thing you are most sure of is that your son left the lights on. You reason from that to the conclusion that the car will not start. In this scenario, knowing that the lights were left on is a reason for believing that the car will not start. You are trying to convince your son that the car will not start, and the fact that he left the lights on last night is the starting point for doing so. We can show the structure of your argument as follows:

Your son left the lights on. Leaving the lights one will drain the battery. A drained battery will prevent the car from starting. Therefore, your car won’t start.

Notice that the structure of this argument is the same as the structure of the explanation example. The only difference is whether you are trying to show that the car will not start or to understand why it will not start after already realizing that it will not. Finding the structure will help you understand the details of the argument or explanation, but it will not, by itself, help you determine which one you are dealing with. For that, you have to determine what the author is trying to accomplish and what the author sees as common ground with the reader. Understanding the structure of what is said can help you become clearer about what the author is doing, so it is a good thing to look for, but understanding the structure is not enough.

Determining whether a passage is an argument or an explanation is thus often a matter of inter- preting the intention of the speaker or writer of the claim. A good first step is to identify the main point or central focus of the passage. What you are looking for is the sentence that will be either the conclusion to the argument or the claim being explained. If the author has not done so, paraphrase the main claim as a single, simple sentence. Try to avoid including words like because or therefore in your paraphrase. Ask yourself, if this is an argument, what is its conclu- sion? Once you have identified the potential conclusion, try to determine whether the author is attempting to convince you that that sentence is true, or whether the author assumes you agree with the sentence and is trying to help you understand why or how the sentence is true. If the author is trying to convince you, then the author is advancing an argument. If the author is try- ing to help you get a deeper understanding, the author is providing an explanation.

It is important to be able to tell the difference between arguments and explanations both when listening to others and when crafting our own arguments and explanations. This is because arguments and explanations are trying to accomplish different goals; what makes an effective argument may not make an effective explanation.

Moral of the Story: Arguments Versus Explanations If the main claim is accepted as true from the beginning, then the speaker or writer may be advancing an explanation, not an argument. If the point of a passage is to convince the reader that the main claim is true, then it is most likely an argument. Of course, you may question an explanation, thus requesting an argument that the explanation is correct.

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Summary and Resources

Chapter Summary This chapter introduced the standard argument form, which is the principal tool that we will employ in the ensuing chapters. We examined the elements of an argument in standard form, starting from the fundamental notion of claim to an argument’s proper parts—premises and conclusion—and the relationship between these, or what we call inference. Although the standard argument form is simple, the relationship between those claims we call premises and those we call conclusions is crucial to distinguishing between different kinds of arguments. Diagramming these relationships is merely one way we can analyze arguments more fully.

In this chapter we also briefly discussed two kinds of arguments—deductive and induc- tive. However, each one of these will be addressed individually in subsequent chapters as we employ them in more sophisticated applications. Additionally, we explored how to identify arguments in the sources we encounter, as well as how to extract what we find and paraphrase it so that it can be presented in the standard form. Finally, we discussed how to distinguish arguments from explanations and presented a simple method for making such a distinction.

As you continue to read this book, remember that logic is not learned by reading alone. Learning logic demands taking notes of structures and terminology, and it requires practice. Accordingly, practice the exercises provided in each chapter. Once you gain mastery of the standard argument form, you will be able to recognize good arguments from bad arguments, and you will be able to present good arguments in defense of your views. This is a powerful skill to have, and it is now in your hands.

Critical Thinking Questions

1. Try to find a political commercial, and outline the argument that is presented in the commercial. Is it easy or difficult to find premises and conclusions in the content of the commercial? Does the argument relate to politics or to something outside of politics? Are there components of the ad that you think attempt to manipulate the viewer? Why or why not?

2. How can you utilize what you have learned in this chapter about arguments in your own life? At work? At home? How does an understanding of being able to outline and structure arguments translate into your everyday activities?

3. Now that you understand the components of an argument, think back to a time that someone you know attempted to provide an argument but failed to do so in a con- vincing fashion. What were the mistakes that this person made in his or her reason- ing? What were the structural or content errors that weakened the argument?

4. Suppose that your child refuses to go to bed. You want to convince your child that he or she needs to get to sleep. You feel the urge to say, “You have to go to bed because I said so.” However, you are now trying to use what you are learning in this course. What argument would you present to your child to try to convince him or her to go to sleep? Do you think that a strong argument would be effective in convincing your child? Why or why not?

5. Suppose you have a coworker who refuses to help you with a mandatory project. You want to convince him that he needs to help you. What premises would you use to support the conclusion that he ought to help you with the project? Assuming that he fails to find your argument convincing, what would you do next? Why?

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Summary and Resources

Web Resources http://austhink.com/critical/pages/argument_mapping.html The group Austhink provides a number of resources on argument mapping, including tutori- als on how to diagram arguments.

http://www.manyworldsof logic.com/index.html The Many Worlds of Logic website discusses many of the topics that will be covered in this book.

Key Terms

argument The methodical defense of a position advanced in relation to a disputed issue; a set of claims in which some, called premises, serve as support for another claim, called the conclusion.

claim A sentence that presents an assertion that something is the case. In logic, claims are often referred to as propositions in order to recognize that these may be true or false.

conclusion The main claim of an argument; the claim that is supported by the premises but does not itself support any other claims in the argument.

conclusion indicators The words that signal the appearance of a conclusion in an argument.

explanations Statements that tell why or how something is the case. Unlike argu- ments, explanations do not involve contested conclusions but, instead, accepted ones.

inference The process of drawing the nec- essary judgment or, at least, the judgment that would follow from the reasons offered in the premises.

premise indicators The words that signal the appearance of a premise in an argument.

premises Claims in an argument that serve as support for the conclusion.

standard argument form The structure of an argument that consists of premises and a conclusion. This structure displays each premise of an argument on a separate line, with the conclusion on a line following all the premises.

Answers to Practice Problems Practice Problems 2.1

1. claim 2. claim 3. claim 4. nonclaim 5. nonclaim 6. claim 7. claim 8. nonclaim 9. claim

10. claim 11. nonclaim 12. claim 13. nonclaim 14. claim 15. nonclaim 16. claim 17. claim 18. nonclaim

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http://austhink.com/critical/pages/argument_mapping.html

http://www.manyworldsoflogic.com/index.html

Summary and Resources

19. claim 20. nonclaim 21. nonclaim 22. claim 23. claim 24. nonclaim 25. claim 26. nonclaim 27. claim 28. claim 29. nonclaim

30. claim 31. nonclaim 32. claim 33. claim 34. nonclaim 35. nonclaim 36. claim 37. claim 38. nonclaim 39. claim 40. nonclaim

Practice Problems 2.2

1. There are three premises: (1) “Every time I turn on the radio, all I hear is vulgar lan- guage about sex, violence, and drugs,” (2) “Whether it’s rock and roll or rap, it’s all the same,” and (3) “The trend toward vulgarity has to change.” The conclusion is “If it doesn’t, younger children will begin speaking in these ways, and this will spoil their innocence.” Notice that the final sentence is an “If . . . , then . . .” statement. Remem- ber that these forms of sentences are single statements. The entire final sentence is the conclusion of this argument.

2. The premise is “Letting your kids play around on the Internet all day is like dropping them off in downtown Chicago to spend the day by themselves.” The conclusion is “They will find something that gets them into trouble.”

3. There are three premises: (1) “Too many intravenous drug users continue to risk their lives by sharing dirty needles,” (2) “This would lower the rate of AIDS in this high-risk population,” and (3) “allow for the opportunity to educate and attempt to aid those who are addicted to heroin and other intravenous drugs.” The conclusion is “This situation could be changed if we were to supply drug addicts with a way to get clean needles.”

4. There are three premises: (1) “His parents drive a Mercedes,” (2) “His dogs wear cashmere sweaters,” and (3) “he paid cash for his Hummer.” The conclusion is “I know that Stephen has a lot of money.” Notice that there are two premises in the final sentence. Remember that words like and and as well as usually indicate that there are multiple statements being made in a single sentence.

5. There are two premises: (1) “they always listen to what their masters say” and (2) “They also are more fun and energetic.” The conclusion is “Dogs are better than cats.” Remember that the word since is often a premise indicator. That means that the state- ment that follows the word since is often a premise.

6. There are two premises: (1) “All dogs are warm-blooded” and (2) “All warm-blooded creatures are mammals.” The conclusion is “all dogs are mammals.” Remember that the word hence is a conclusion indicator. It often comes before the conclusion of an argument.

7. There are two premises: (1) “it is an over-21 show” and (2) “Jeffrey, James, and Sloan were all carded when they tried to get in to the club.” The conclusion is “Chances are that I will not be able to get in to see Slipknot.” Remember that the word since is

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Summary and Resources

often a premise indicator. That means that the statement that follows the word since is often a premise.

8. There are two premises: (1) “the best of all possible worlds would not contain suf- fering” and (2) “this world contains much suffering.” The conclusion is “This is not the best of all possible worlds.” Remember that the word because is often a premise indicator. That means that the statement that follows the word because is often a premise.

9. There are two premises: (1) “Some apples are not bananas” and (2) “Some bananas are things that are yellow.” The conclusion is “some things that are yellow are not apples.” Remember that the word therefore is a conclusion indicator. It often comes before the conclusion of an argument.

10. There are two premises: (1) “all philosophers are seekers of truth” and (2) “no philosophers are evil humans.” The conclusion is “no evil human is a seeker after truth.” Remember that the words it follows that are conclusion indicators. They often come before the conclusion of an argument. Also, remember that the word since is often a premise indicator.

11. The premise is “All squares are triangles and all triangles are rectangles.” The con- clusion is “all squares are rectangles.” Remember that the word so is a conclusion indicator. It often comes before the conclusion of an argument.

12. There are two premises: (1) “Deciduous trees are trees that shed their leaves” and (2) “Maple trees are deciduous trees.” The conclusion is “maple trees will shed their leaves at some point during the growing season.” Remember that the word thus is a conclusion indicator. It often comes before the conclusion of an argument.

13. The premise is “most philosophy professors are rich.” The conclusion is “Joe must make a lot of money teaching philosophy.” Remember that the word since is often a premise indicator. That means that the statement that follows the word since is often a premise.

14. There are two premises: (1) “all mammals are cold-blooded” and (2) “all cold-blooded creatures are aquatic.” The conclusion is “all mammals must be aquatic.” Notice that there are two premises in the first sentence. Remember that words like and and as well as usually indicate that there are multiple statements being made in a single sentence.

15. There are two premises: (1) “If you drive too fast, you will get into an accident” and (2) “If you get into an accident your insurance premiums will increase.” The conclu- sion is “if you drive too fast, your insurance premiums will increase.” Remember that the word therefore is a conclusion indicator. It often comes before the conclusion of an argument.

16. There are three premises: (1) “The economy continues to descend into chaos,” (2) “The stock market still moves down after it makes progress forward,” and (3) “unemployment still hovers around 10%.” The conclusion is “It is going to be a while before things get better in the United States.” Notice that there are two premises in the second sentence. Remember that words like and and as well as usually indicate that there are multiple statements being made in a single sentence.

17. There are two premises: (1) “The athletes are amazing” and (2) “it is extremely com- plex.” The conclusion is “Football is the best sport.” Notice that there are two premises in the second sentence. Remember that words like and and as well as usually indicate that there are multiple statements being made in a single sentence.

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Summary and Resources

18. The premise is “I hear that it has amazing special effects.” The conclusion is “We should go to see Avatar tonight.”

19. There are two premises: (1) “All doctors are people who are committed to enhancing the health of their patients” and (2) “No people who purposely harm others can con- sider themselves to be doctors.” The conclusion is “some people who harm others do not enhance the health of their patients.” Remember that the words it follows that are a conclusion indicator. When you see these words, think “a conclusion is coming.”

20. There are three premises: (1) “Guns protect people,” (2) “They give people confi- dence that they can defend themselves,” and (3) “Guns also ensure that the gov- ernment will not be able to take over its citizenry.” The conclusion is “Guns are necessary.”

Practice Problems 2.3

1. 2

3. 1

4. 1

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2 3+

Summary and Resources

2 3+

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