THOUGHT AND KNOWLEDGE

Trade your old body for a new one now through an amazing scientific breakthrough. Doctors and medical technicians have made it possible for people like you and me to lose weight quickly and permanently. Tested at university labs, retested at clinics and major hospitals and acclaimed by doctors all over the world, finally there is something that helps you lose weight. If years of stubborn fat build up have been your problem, NOW AT LAST THERE IS A WAY TO ELIMINATE FAT, A WAY TO LOSE WEIGHT FAST AND EASILY. We call it XXXXXXX because it totally attacks excess fat and fluids that have plagued most people for years. … Everyday you will feel stronger and full of pep and energy as the excess weight you have carried for so long is carved off your body. … DON’T LET THIS GOLDEN OPPORTUNITY AND CHANCE OF A LIFETIME PASS YOU BY. Just fill out the coupon below and let it be the ticket to a slimmer you. So, what are you waiting for?

I hope that you were not looking for a coupon for this marvelous weight loss product. The paragraph above was taken (virtually) verbatim from a full-page advertisement in a popular fashion magazine. The only change that I made was to omit the name of this “miracle” diet. The name has a chemical sound to it. It’s multisyllabic and ends with a number. The name sounds like a chemical formula. I had trouble selecting which advertisement I wanted to use here because there were so many that made numerous unsupported claims. Advertisements like this one can be found in most magazines and newspapers. I’ll refer back to this advertisement later in this chapter when I talk about analyzing arguments and recognizing fallacies. Hold onto your money until you’ve read this chapter.

The Anatomy of an Argument

Neither a closed mind nor an empty one is likely to produce much that would qualify as effective reasoning.

—Ray Nickerson (1986, p. 1)

The technical meaning of the word “argument” is different from its everyday meaning. We say two people “are having an argument” when they disagree about something in a heated or emotional way. More technically, an argument consists of one or more statements that are used to provide support for a conclusion. The statements that provide the support for a conclusion are called the reasons or premises of the argument. The reasons or premises are presented in order to persuade the reader or listener that the conclusion is true or probably true. Let’s consider an example. Suppose that I want to convince you to stay in college until graduation. Here are some reasons (premises) that I could give. You can think of this as an addition problem with each premise summing to the conclusion.

Premise #1:	College graduates earn more money than college dropouts or people who have never attended college.
+ Premise #2:	College graduates report that they are more satisfied with their lives than people who have not graduated from college.
+ Premise #3:	College graduates are healthier and live longer than people who have not graduated from college.
+ Premise #4:	College graduates have jobs that are more interesting and more responsible than people who have not graduated from college
Conclusion:	You should graduate from college.

Arguments are sometimes called “the giving of reasons.” Harman (1986) calls this process “a change in view” because the objective is to change an “old view” or belief into a “new view” or belief with reasoning.

Every argument will have one or more premises (or reasons) and one or more conclusions. Usually, there will be several premises for one conclusion, but other combinations (one premise for several conclusions and several premises for several conclusions) are possible. If you cannot identify at least one premise and at least one conclusion, then it is not an argument. Of course, in everyday, natural-language arguments, the premises and conclusions are not labeled. They are usually embedded in extended prose. The extended prose could be a paragraph, a section or chapter of a book, or even an entire book or semester-long class.

Here are some examples of prose that are not arguments:

• I like my critical thinking course better than my chemistry course. (No reasons are given for this preference.)

• We drove up to the mountains, went skiing, and then drove home. (This is just a descriptive list of activities linked together. There are no reasons or conclusions.)

• Buy your burgers at Burgerland. (No reasons given, but reasons are often inferred from context in statements like this one.)

• We saw the Martians land. (This is a simple description.)

• Never trust anyone over 30. (This is an opinion without reasons.)

• Is dinner ready? (Simple question.)

It may seem that it should be fairly simple to determine whether a statement or set of statements contain an argument, but in everyday language most arguments are incomplete. Sometimes the premises aren’t stated, but are inferred, and other times the conclusion is unstated. Sometimes arguments are deliberately disguised so that it may appear that the speakers are not supporting some conclusion, when they really are.

Premises

The premises are the reasons that support a conclusion. They are the “why” part of an argument. In everyday language, they can appear anywhere among a set of statements. Sometimes, the conclusion will be stated first followed by its premises. (Here is what I believe and the reasons for this belief are. …) Other times the conclusion may be presented last or embedded in the middle of a paragraph or other text with premises both before and after it. Premises are not always easy to recognize. There are certain key words, called premise indicators or premise markers that often signal that what comes after them is a premise. Although premise indicators are not always followed by a premise, they often are, and for this reason, it is a good idea to check for these key words when identifying premises. These terms often indicate that what follows is a reason.

Premise Indicators

because

for

since (when it means because and not the passage of time)

given that (or being that)

as shown by

as indicated by

the reasons are

it may be inferred (or deduced) from

the evidence consists of

in the first place (suggests that a list of premises will follow)

secondly

seeing that

assuming that

it follows from

whereas

Here are some simple examples of the use of premise indicators:

• You should graduate from college because you will earn more money with a college degree.

• The need for the United States to send troops to Central America is indicated by the buildup of armed rebels in countries neighboring those with civil wars.

• Seeing that the current policy of supplying organ transplants is benefiting the rich, a new program is needed.

Premises can be “matters of fact” or “matters of opinion” or both. Consider, for example, the following sentences:

• All teenagers should be taught safe sex practices because of the risk of AIDS and other sexually transmitted diseases. (The reason is a matter of fact.)

• All teenagers should be taught how to knit because this will provide them with an enjoyable hobby. (The reason is a matter of opinion.)

Conclusions

The conclusion is the purpose or the “what” of the argument. It is the belief or point of view that is supported or defended with the premises. Both the premises and the conclusion are important, and both are essential components of any argument.

It is usually easier to identify the conclusion of an argument than the other components. For this reason, it is a good idea to start with the conclusion when you are analyzing arguments. There are conclusion indicators or conclusion markers that indicate that what follows is probably a conclusion. As with premise indicators, they do not guarantee that a conclusion follows them.

Conclusion Indicators

therefore

hence

thus

consequently

then

shows that (we can see that)

accordingly

it follows that

we may infer (conclude) (deduce) that

in summary

as a result

for all these reasons

it is clear that

Here are some simple examples of the use of conclusion indicators:

• Based on all of the reasons just stated, we can conclude that the flow of illegal drugs must be stopped.

• In summary, postal rates must be increased because we can no longer afford to run the postal system with a deficit.

• We have had very little rain this season. Consequently, water will have to be rationed.

Has my use of the word “simple” to describe these examples made you feel uneasy? Have you begun to expect that things will soon get more complex? If so, you are right. Natural language is complex and so are natural-language arguments. (A natural language is a language that has evolved over time for the purpose of communication between people. Artificial languages are those languages that were created for special purposes, such as computer languages.) Although all arguments must contain at least one argument and one conclusion, most arguments consist of additional components. Three additional components will be presented here. They are assumptions, qualifiers, and counterarguments.

Assumptions

With enough assumptions, any policy can be justified.

—Tim Brennan (January 12, 2001, from A Guide to Understanding how Washington Really Works)

An assumption is a statement for which no proof or evidence is offered. Although assumptions can be either stated or unstated (implied), they are most often unstated. Assumptions are important components in arguments, and they are the most often forgotten part because they are often omitted. The reader or listener will usually have to supply the missing assumptions.

The arguments that are used to build the main argument are called subarguments. The main argument in an extended passage and is called the main point. The kinds of arguments that are often found in books, book chapters, and sometimes sections of chapters proceed in stages with subarguments linked to provide support for a main point.

Here is an example of an unstated assumption, taken from a catalogue that sells copper bracelets. I have altered it only slightly for this context.

For hundreds of years people have worn copper bracelets to relieve pain from arthritis. This folklore belief has persisted and copper bracelets continue to be popular. These bracelets promote close contact between the copper and your wrist.

The writers of this advertisement expect that readers will assume that copper can help alleviate the pain of arthritis and that the “medical” effect is enhanced by the close contact with the wrist. Notice that this is never stated—it can’t be because there is no evidence that shows that copper has any effect on arthritis. However, this advertisement for copper bracelets is clearly written to suggest that it works. (Many people believe that it does.) Furthermore, there is a suggested assumption that the popularity of copper bracelets is due to its medical effects. Maybe they have just become fashionable, or cheaper, or better advertised, or perhaps there are just more people with arthritis who are willing to believe anything that promises to relieve their pain. We’ll discuss the need to consider missing information and alternative conclusions in a later section of this chapter.

Qualifiers

A qualifier is a constraint or restriction on the conclusion. It states the conditions under which the conclusion is supported. An example might be helpful:

Let’s dissect this paragraph into its component parts:

The conclusion is: A national college-level testing program is needed.

A premise is: It is important that we have some indicators of what and how much students are learning in college. (This is the reason that supports the conclusion. It tells us why we should believe that the conclusion is true.)

An unstated assumption is: A national college-level testing program is a good way to indicate what students are learning.

A qualifier (or limiting condition) is: The conclusion is valid only when the assessment is related to what is the curriculum.

As you can see from this example, a qualifier states the conditions under which the conclusion is valid. It sets limits or constraints on the conclusion.

Counterarguments

Critical thinking requires a sense of the complexity of human issues.

—Alan Sears and Jim Parsons (1991, p. 64)

Sometimes, an extended argument will state reasons that support a particular conclusion and reasons that refute the same conclusion. The set of statements that refute a particular conclusion is called a counterargument. Let’s extend the previous argument so that it now also contains a counterargument.

It is important that we have some indicators of what and how much students are learning in college. For this reason, a national college-level testing program is needed. However, if the national assessment is not related to the subjects taught in the college curriculum, then it will not be a valid measure of college-level learning. Of course, the results of a national assessment of college students could be misused in a way that would keep good students from entering graduate or professional school.

I hope that you are paying careful attention to the way the additions are altering the argument. As presented above, the conclusion, premise, assumption, and qualifier remain the same. The counterargument presents a reason for not having a national college-level test. The reason presented (results could be misused) is counter to the conclusion that we should have a national test—that is why these statements are called counterarguments. Even with the addition of the counterargument, the conclusion remains unchanged. The argument was written in a way that suggests that the counterargument is weaker than the main argument. The point being made is that despite the counterargument, we should still have a national test of college students—the conclusion is the same.

Does this particular example make you uneasy? Can you think of other premises that might support a different conclusion? If so, you have already begun to anticipate the content of the section on how to evaluate arguments.

Diagramming the Structure of an Argument

Argument is a central feature of the resolution of scientific controversies.

—Driver, Newton, and Osborne (2000, p. 287)

Arguments are a related series of statements that are made in an attempt to get the reader or listener to believe that the conclusion is true. In order to analyze or dissect an argument, we need to know not only its component parts, but also how the parts are related to each other. Arguments are made up of parts that are synthesized or put together when an argument is made, and parts that can be disassembled as one way to understand them. The parts that make up an argument are premise(s), conclusion(s), assumption(s), qualifier(s), and counterargument(s). The only restriction on arguments is that each must have at least one premise and one conclusion. Beyond this, a large variety of arrangements is possible. A good way to understand the relationships between the parts of a prose passage is to draw a diagram. Diagrams are used in every chapter of this book because they require the drawer to be specific about the relationships being depicted and to think about underlying relationships. Drawing a diagram is a good general thinking strategy.

Let’s consider the simplest argument with only one premise and one conclusion.

1	2
[Be sure to get plenty of aerobic exercise] because	[aerobic exercise will help you build a strong cardiovascular system.]

This argument is made up of two statements. I have indicated them by putting brackets around each and numbering them “1” and “2.” A statement is a phrase or sentence for which it makes sense to ask, “Is this true or false?” The answer to this question is not relevant here; that is, it doesn’t matter if the statement really is true or false, only whether it makes sense to ask if the phrase is true or false. For example, the following are NOT statements: Rinse the spaghetti. Who lives here? Is that house for sale? Wow! Commands, questions, and exclamations are not statements because it makes no sense to ask if they have a “truth value,” that is, it makes no sense to ask if they are true or false.

Look again at the simple argument in the paragraph above. Identify which of the two statements is the conclusion and which is the premise.

Conclusion: [Get plenty of aerobic exercise]. Remember, the conclusion is the statement that indicates what you should believe or what you should do. (I started with the conclusion because this is often the easiest part of the argument to identify.)

Premise: [Aerobic exercise will build a strong cardiovascular system.] This is the “why” part of the argument that gives a reason for believing the conclusion.

A diagram of this relationship shows that the conclusion is supported by the premise:

[1] [Get plenty of aerobic exercise]—the conclusion

↑

[2] [Aerobic exercise will help you build a strong cardiovascular system]—the premise

As you can see, the statement that is the conclusion [1] is at the top of the diagram and the premise [2] is holding it up. This is shown with the arrow that points from the premise to the conclusion.

Now let’s consider an argument in which two different premises support one conclusion. Again, I have bracketed each statement and numbered each:

1	2	3
[Be sure to get plenty of aerobic exercise] because	[aerobic exercise will help you build a strong cardiovascular system] and	[it will lower your resting heart rate].

[1] Conclusion: Get plenty of exercise.

[2] Premise: Aerobic exercise will build a strong cardiovascular system.

[3] Premise: Aerobic exercise will lower your resting heart rate.

A diagram of this argument will look like this:

In this diagram, we have two premises supporting one conclusion. Both of the arrows point to the same conclusion. This is called a convergent structure because both premises converge onto the same conclusion; that is, they are both reasons why you should get plenty of aerobic exercise. Longer arguments will often contain several premises that support a conclusion.

Let’s consider an example in which there are three premises and two conclusions.

1	2
[Taylor was late for school] because	[she over-slept] and
3	4	5
[she had to stop for gas.]	[Taylor doesn’t care much about school]; therefore	[she is often late.]

In the chapter on deductive reasoning, I talked about skeleton structures—sort of fill-in-the-blank structures where it doesn’t matter what gets filled in. The skeleton is the “bare bones” of an argument, the place where you hang your statements. Let’s reduce this argument to its skeleton:

[1] because [2] and [3]. [4] therefore [5].

This is a good way to think about premise and conclusion indicators. Any statement that follows because will probably be a premise ([2] and [3]), and any statement that follows therefore will probably be a conclusion ([5]).

Can you see how [2] and [3] are premises for [1], and [4] is a premise for [5]?

A diagram of this argument will look like this:

This is an example of two separate arguments in the same paragraph.

Guidelines for Diagramming Arguments

In understanding complex arguments, it is wise to identify the conclusions, premises, assumptions, qualifiers, and counterarguments, and then diagram the structure of their relationship. It is often useful to turn the argument into its skeleton form so that relationships can be seen more clearly. The major difficulty in using this procedure is that complex arguments have complex structures. Sometimes there is more than one possible interpretation and, correspondingly, more than one possible diagram. Sometimes the difficulty lies in deciding if a statement is really part of a subargument or part of the main argument. In longer text, you will often have to restate premises, conclusions, counterarguments, assumptions, and qualifiers in your own words. This process can involve reducing whole chapters of books to single statements. While this can be difficult, it is an excellent strategy for comprehension. Often the process of diagramming will reveal what is wrong or right about a certain argument. If more than one diagram of an argument is possible, then you can consider each separately. Does one diagram provide stronger support for the conclusion? Is one diagram a “truer” representation of the statements being made?

Using Argument Structure when Writing and Speaking

In your own writing and speaking, you often need to persuade an audience that your conclusions are correct. Before you write or make an oral presentation, be sure that you can answer the following questions:

1. What is your conclusion? In other words, what is the point (or points) you want to make? Arguments are made, or constructed, from their parts, and there is no argument if there is no conclusion. Although this question is first on the list, do not start with the conclusion that you want or believe to be true and then find reasons to support it. Look at reasons and evidence that address a particular issue in as unbiased a way as possible to determine what conclusion is best supported. The idea of taking a position on a controversial issue and then finding support for that position is a close-minded approach to thinking. If an issue is controversial, then there should be support for both sides (or more than two sides), and critical thinkers should be able to cite support for multiple positions and decide on the best conclusion by weighing all of the available evidence.

2. What are the reasons that support your conclusion? How strong are they?

3. What assumptions are you making? Are they reasonable assumptions? Should they be explicitly stated?

4. What are the conditions under which the conclusion might not be true? In other words, are qualifiers needed?

5. What are the counterarguments? Why should a reader or listener not believe in your conclusion? What alternative conclusions have you actively considered?

6. What’s missing? Are other conclusions possible given the reasons? Are there other reasons? Other counterarguments? Other assumptions? This step requires that you look beyond the information that you are using to consider what else might be important.

Actively Open-Minded Thinking

People display myside bias: they evaluate evidence, generate evidence, and test hypotheses in a manner biased towards their own opinions. … People also display a one-sided bias: they prefer arguments that are onesided rather than arguments that reflect many different perspectives.

—Keith E. Stanovich and Richard F. West (2008, p. 130)

Another reason why you should learn how to analyze arguments concerns what Seech (1993) calls “points of logical vulnerability.” There are some topics about which we have trouble being objective. For example, I know that it would be difficult for me to be objective about the Ku Klux Klan. This is an emotional topic for me, and I would have great difficulty concluding anything positive about this group. If I used argument analysis, especially by reducing an argument to its skeleton and then diagramming its structure, then I could assess the strength of the support for a conclusion more fairly than I could without this sort of analysis. Of course, I could still decide that any belief or action that they are advocating is wrong.

There is a theme that reoccurs in almost every chapter in this text—the pervasiveness of the confirmation bias—the bias to look for and prefer information that confirms prior beliefs (O’Brien, 2009). Some authors call it “my-side bias” as a way of emphasizing the strong general tendency to prefer evidence that supports what they believe to be true (Stanovich & West, 2008). It is a very strong influence on the way many, perhaps all, of us think and feel, and for the most part, we are unaware of its effects. Information that supports conclusions that we believe to be true just seems better than information that does not. Furthermore, the bias to prefer information that is consistent with our preexisting biases does not vary as a function of intelligence (Stanovich & West, 2008). In a study of the relationship between intelligence and critical thinking, people who scored high on standardized tests designed to assess intelligence were as likely to show a bias for explanations they preferred as those who scored lower on the intelligence test.

Think about some topic about which you have strong feelings—it could be gun control, censorship, school vouchers, innate differences between the sexes, the United Nations, the death penalty, same-sex marriage, or anything else where the conclusion (what to do or believe) is clear to you. Now suppose that you come across strong evidence that supports a different conclusion than the one you prefer—let’s say it makes a strong case for allowing open access to guns and you favor strict control of gun access or you are given data that show that the death penalty increases the crime rate and you favor the death penalty. How would you respond? I suppose that you would want to know more—how the data were collected, what the data actually showed—but assume for now that there are strong data that support a conclusion you totally oppose. Now what? Baron (1993) used the term “actively open-minded” to describe people who can change a cherished belief when given good reasons to do so. It turns out that actively and honestly processing information that runs counter to prior beliefs is very difficult, but there are people who can remain open-minded enough to evaluate an argument objectively, independent of their prior beliefs (Baron, 1995; Stanovich & West, 1997). It is not impossible to be fair-minded, but it is difficult.

Historical Evidence

How do you know that World War II really happened and that it is not just a made up story to serve as the background for Hollywood war movies? When I asked this question in class one day, a student told me that he knew that World War II really happened because his grandfather was there—his grandfather fought in the war, and it was as horrible as we have read in our history books. Based on the information we had, it was easy to conclude that the student’s grandfather was a credible source of information for this topic. In addition, he had war injuries to support his story. The question may seem strange, but there are groups of people who claim that stories about World War II are exaggerated (or lies) and that there was no mass extermination of the Jews in Europe. Similarly, there are groups that claim that slavery in the United States was not so bad (as mentioned in the last chapter). In fact, there may be groups that deny everything we know about history and science. How can we honestly assess these claims? It seems that all “fringe” groups that advocate a point of view that is not well supported use similar methods in constructing their arguments.

How can we analyze historical arguments? In an outstanding analysis of the arguments used by “Holocaust Deniers’ (people who claim that the Holocaust never happened or that it has been exaggerated), Shermer (1997, p. 212) wrote that these groups

(a)	concentrate on any weakness in their opponents’ argument instead of providing strong evidence to support their own argument;
(b)	exploit errors in the opposing argument—by focusing on a mistake made by someone who supports an opposing view, they can suggest that all or most of the evidence is wrong;
(c)	take quotes out of context so that the meaning is altered;
(d)	recast honest debates between scholars to make them seem as though the honest scholars disagree about fundamental issues, when in fact they may disagree only about tertiary issues; and
(e)	focus on what is not known rather than what is known.

Historical arguments are correctly evaluated with the same methods that are used in anthropology, botany, geology, and every other field. Converging evidence (remember converging arguments from the earlier section?) shows that demographic data, historical records, eye witness accounts, physical evidence, etc. all support the conclusion that the holocaust deniers twist and distort evidence and argument to advance a racist agenda. A basic understanding of arguments—reasons, evidence, conclusions, counterarguments, etc.—can protect you from falling prey to fringe groups who are trying to advance a political agenda (often a racist agenda) that is not supported by data.

Evaluating the Strength of an Argument

Advertising persuades people to buy things they don’t need with money they ain’t got.

—Will Rogers (1879–1935)

All arguments are not equally good or equally bad. Think about how your belief about an issue can be swayed or reinforced as each speaker in a debate presents the reasons and conclusions supporting or refuting a position. In this section, we consider how to evaluate the strength of an argument.

Arguments are evaluated by how well they meet three criteria. The first criterion concerns the acceptability and consistency of the premises. The second criterion concerns the relationship between the premises and the conclusion. Do the premises support the conclusion? Does the conclusion follow from them? The third criterion concerns the unseen part of the argument. What’s missing that would change your conclusion? Let’s consider each of these criteria in turn.

Acceptable and Consistent Premises

No man can think clearly when his fists are clenched.

—George Jean Nathan (quoted in Byrne, 1988, p. 390).

The premises are the “why” part of an argument. The premises must be acceptable. A premise is acceptable when it is true or when we can reasonably believe that it is true. Let’s consider what this means. If I say that the sun is hot, this is an acceptable premise. I have never touched the sun, but many experts in the field have said that the sun is hot. Much of what we believe to be true comes from experts’ statements and personal and common or shared knowledge. Similarly, I have no direct, first-hand knowledge of bacteria, but it is reasonable to believe that they exist. Acceptable premises are commonly acknowledged “truths” of science. I believe that California is larger than New Jersey although I have never measured them. You could probably give a long list of “facts” that are commonly believed to be true. These are examples of acceptable premises.

Premises that are false are unacceptable. Examples of false premises include: men can give birth to babies, whales can fly, all mammals are dogs, and Spanish is the primary language of Canada. I do not want to get into the philosophical considerations of how we can ever know “truth.” Personal or common knowledge and expert testimony will be the guide for determining acceptability.

Unfortunately, acceptability is not an either/or proposition in which a premise is either acceptable or it is not. Sometimes, part of the job of analyzing an argument involves determining how acceptable a premise is. This may require research on your part. Suppose that you are listening to an argument about the safety of a nuclear facility near your home. The corporation that wants to build the facility argues that it is safe; therefore, you have nothing to worry about. One way to decide about the acceptability of this premise is to spend some time in the library reading about the kinds of accidents that have occurred in the past, the kinds of safety precautions that are used, and whether there were important benefits in communities that have such facilities. You will also need to consider the statements of experts in this area.

In a good argument, the premises are also consistent. When several premises are presented to support a conclusion, they must not contradict each other. For example, an argument in which one premise states that we have to reduce unemployment in order to improve the economy and another premise states that we have to increase unemployment in order to improve the economy is an argument that contains inconsistent premises. Sometimes, when premises are inconsistent, it is possible to eliminate one of them because it is weak or faulty. If you can eliminate the inconsistency between the premises, you will be able to judge more clearly the strength of the argument.

Credibility

Trustworthiness refers to the willingness of a source to provide accurate, reliable information, with trustworthy sources influencing readers’ beliefs, attitudes, and expectations more so than untrustworthy ones.

—Jesse R. Sparks and David N. Rapp (2011, p. 230)

What makes an expert credible? In deciding whom and what to believe, you need to consider the source of the information. Ask yourself the following questions about an expert who is presenting the reasons for a belief:

1. Is the “expert” a recognized authority in the same field in which she is providing testimony?

2. Is the expert an independent party in this issue? If the expert who says the nuclear facility is safe was hired by the corporation that owns the laboratory, then her testimony is suspect. The testimony is not necessarily dishonest or wrong, but you should be wary because a motive for personal gain maybe involved.

3. What are the expert’s credentials? Did she write several journal articles on the subject, which were then published in respected journals, or is her expertise documented with a single night school course in the topic? Is the expert current in the field?

4. Does the expert have specific and first-hand knowledge of the issue? She could conclude that nuclear facilities are generally safe, but have no direct knowledge of the one being proposed. Did she check the plans for safety features?

5. What methods of analysis were used by the expert? Are there standard safety assessments for nuclear facilities? Were these used?

It is interesting to note that a similar list of variables was found in a study of what makes jurors believe experts. Legal researchers found that the most important factors in the way jurors’ assessed credibility were the expert’s qualifications, reasoning, familiarity with the particular case, and impartiality (Shuman & Champagne, 1998).

Reread the advertisement presented at the beginning of this chapter that states that we can “eat all day and still lose weight.” Who are the doctors and universities that support this claim? (No names are given. You should immediately begin to question the credibility of this information.) Was their expertise in weight loss? What are their credentials? Are they independent or will they make money if you buy this product? What were the methods of analysis that were used to document the statement that it will make you feel stronger and full of pep? (None were mentioned.) Are the claims made in this advertisement credible?

Decisions about the acceptability of premises will often depend on how you evaluate the source of the information. When you have two experts who disagree, which is frequently the case, you need to understand the nature of the disagreement and their relative expertise. Are they disagreeing on research findings or the interpretation of those findings? Try to zero in on the specific points on which they disagree so that you can scrutinize these points.

Carlson (1995) distinguished between experts with regard to matters of reality and matters of value. When the topic concerns “reality” (e.g., Do people who live near nuclear facilities plants suffer from more illnesses than people who do not live near them?), then the expert can provide evidence, such as the results of studies, that support her conclusion. When the topic concerns values, the identification and role of the expert is more difficult. For example, should euthanasia be allowed? This sort of question involves issues such as whether anyone has the right to terminate his own life, and experimental data will not be useful in formulating a conclusion in this situation. A chemist might be a credible expert for questions concerning chemical warfare, but who is a credible expert for questions of euthanasia? Are the opinions of medical personnel, clergy, or ordinary citizens equally good in making these decisions? There are few guidelines for selecting credible experts in matters of value. Fischhoff (1993) is an expert on expertise. As he wisely notes, by definition, experts know more about some topic than most of us. However, expert knowledge is always incomplete and people can legitimately disagree about a wide range of topics, such as which risks are worth taking.

The Credibility Crisis

The rapid, phenomenal expansion of information on the Internet has created a credibility crisis. Almost anyone can provide information on almost any topic on the Internet, and it is easily accessible with a few clicks of a mouse. Users must know how to decide if the source of the information is credible. Some sites have “seals of approval” from credible groups like the American Association for the Advancement of Science, but others are so junky that reading from them might be closer to a crime than a legitimate educational experience. Sometimes, the site looks great—spiffy graphics and science-sounding names, but after a few screens are read, advertisements pop up to sell you something or an obviously biased message is shown.

When evaluating information from a web site, look for the following (suggestions from Tate & Alexander, 1996):

(a)	The authority—Who is sponsoring the site? What are the authors’ qualifications?
(b)	Accuracy—Where did the information come from? Are the data clearly labeled?
(c)	Objectivity—Is the site a public service or is it just a fancy “sales-pitch?”
(d)	Currency—When was the site last revised? Is the information still relevant?
(e)	Coverage—Is the information complete?

Premises that Support the Conclusion

Consider the following argument:

It is important that we elect a prime minister from the New Democratic Party (a political party in Canada) because the rain in Spain falls mainly on the plain.

I hope that your response to this was, “huh?” The premise or reason why we should support a candidate from the New Democratic Party had nothing to do with it. The rain in Spain is unrelated to political elections in Canada. In technical terms, the premise does not support the conclusion.

In determining the relevance or relatedness between the premises and the conclusion(s), I like to use an analogy to a table. The conclusion is the top of the table and the premises are the legs. When the premises are unrelated to the conclusion, they are off somewhere in another room and cannot support the table. It is easy to detect instances in which the premises are totally unrelated to the conclusion. Other examples are more difficult as relatedness is a matter of degree. Premises can be more or less related to the conclusion.

Determining the relatedness between the premises and the conclusion can be tricky. This is exactly the sort of determination that judges are required to make all of the time. Consider a rape case in which the defense wants to show that the woman agreed to sexual intercourse. Is her previous sexual behavior related to this issue? Most of the time, the courts have ruled that a woman’s past sexual history is unrelated to whether she was coerced at the time in question, but under special circumstances, such evidence may be admissible because the judge decides that it may be related to a particular case.

The premises not only have to be related to the conclusion, they also have to be strong enough to support the conclusion. Some authors call this condition adequate grounds. When premises provide good support for the conclusion, we say that there are adequate grounds for believing that the conclusion is true or likely to be true.

Let’s return to the table analogy. Think of the conclusion as a solid wooden table top. A solid wooden table top will topple over if we try to support it with a few toothpicks. The only way to support it is to use one or more strong legs or many weaker legs that, when used together, will form a strong base of support. These possibilities are depicted in Figure 5.1.

Figure 5.1 Table analogy for understanding the strength of an argument. The tabletop is the conclusion and the legs are the premises. Strong arguments have a firm base of support.

Let’s consider some examples of strength of support.

1	2
1. [Marion and Engelbert have filed for divorce]. Therefore,	[they plan to get a divorce].

As before, I have bracketed and numbered the statements.

In skeleton form, this is [1] therefore [2].

I hope that you can see that statement [1] is a reason for statement, and [2] is the conclusion. Since we have one reason and one conclusion, this is an argument.

The unstated assumption that they are married will be omitted from the diagram because it is not relevant to the point being made; but if it were included, it would point to [1].

Graphically, this becomes:

I have rated the strength of support for the conclusion as strong because I believe that filing for divorce is very strong evidence that they plan to get divorced (although there are other possibilities which is why it is not absolutely certain).

1	2
2. [Marion and Engelbert had eggs for breakfast]. Therefore,	[they plan to get a divorce].

In skeleton form, this is still [1] therefore [2].

Because the premise is unrelated to the conclusion, it provides no support for the conclusion.

In this example, the reason provides no support for the conclusion. We have no reason to believe that they plan to get a divorce.

1	2
3. [Marion and Engelbert had a fight this morning.] Therefore,	[they plan to get a divorce].

The skeleton structure is still [1] therefore [2].

In this example, the premise is related to the conclusion, but the support is weak.

This example contains five statements. Statement [5] is the conclusion. The other four statements are premises for the conclusion. Let’s consider each premise and decide how well it supports the conclusion.

[5]: Marion and Engelbert plan to get a divorce. This is the conclusion.

[1]: Marion and Engelbert had a fight this morning. (weak)

[2]: They fight every day. (weak)

[3]: Engelbert is moving out to live with his mother. (moderate)

[4]: Marion made an appointment with a divorce attorney. (strong)

In this example, there are multiple premises to support the conclusion. Taken together, they provide strong support.

Look at the list of premises. With only the first one, the support for the conclusion was very weak. The addition of the second made the support somewhat stronger because there were now two separate weak premises, which are stronger together than one weak premise. As additional premises were added, support for the conclusion increased. This is an example of a convergent argument structure in which multiple premises point to (converge on) the same conclusion. Additional premises, even weak ones, increase the strength of the argument. Using the table analogy, ask yourself if the table top has a sound base of support or is it shaky and easy to topple over.

You may have been looking for rules or guidelines to determine the strength of support. There really are no firm rules, only guidelines. How you judge the strength of an argument depends on many personal factors, including what you already know about the topic, your personal values, and how you make judgments. Some psychologists and others have advocated for teaching children and adults about values, which would include teaching them to view complex issues from multiple perspectives—a technique that is frequently used in critical thinking instruction, although we do not usually think of this as “teaching values.” Thinking, at its heart, is still a very personal activity. Although there are many skills that you can learn that will improve how you think, we are in no danger of turning all thinking into a rigid set of steps that will make us all think the same.

Here is a good example where thoughtful people disagree. How important is a candidate’s personal life in determining whether the candidate should be elected? Is it an indication that the candidate will not be honest if you know that he cheats on his spouse? Some people believe that anyone who cheats in marriage will be dishonest in other situations; others believe that the two are unrelated. Public reaction to the sexual relationship between Monica Lewinsky, a White House intern, and former U.S. President Bill Clinton showed that there were many different opinions about the relevance of this relationship to Clinton’s job as president. Similarly, in Russian elections, not long ago, the leading candidate was known to have a problem with alcohol. How important would this be in your decision of whether to vote for this candidate? In answering this question, you would also want to know about the other candidates running for office and the extent of the alcohol problem, but ultimately, many people disagree over issues such as these.

Missing Components

They will try to tell you to prove you are right; I tell you to prove you are wrong.

—Louis Pasteur (1822–1895)

Most arguments are written to persuade the reader or listener that a conclusion is true or probably true. Good examples of this can be found in advertisements and political rhetoric. A big problem in attempts to persuade is missing and distorted claims. In other words, it is the missing parts of most arguments that are often the most important parts. In order to evaluate the quality of an argument, you need to consider what has been left out.

When evaluating an argument, consider each component separately and think about ways the statements could have been distorted and what has been omitted. Let’s analyze a more complicated argument with an example that is paraphrased from a newspaper editorial written by a resident of Douglas, Arizona (Skippar, 2012) in response to an article that advocated the legal use of marijuana for medical conditions. This editorial appeared in the Douglas Dispatch on May 9, 2012.

In this commentary, the author argues against the legal use of marijuana for medical conditions. I have excerpted sections from the original article. Consider the conclusion, the support for the conclusions, the strength of the evidence, the counterarguments, and any missing components.

I am opposed to [name of person] receiving a permit to grow medical marijuana in our neighborhood. She just doesn’t have all the facts. I have enclosed articles from the Denver Post and other sources stating there is criminal activity surrounding medical marijuana growing and dispensary facilities in Denver and elsewhere. While crime in general may not go up appreciably, criminals are going after medical marijuana facilities because, quite frankly, they are easy targets. The criminals have just changed their venue. Marijuana is easy to sell illegally on the street for as much as $300 to $600 an ounce, which makes it the perfect thing to steal. According to law enforcement officials, the other advantage to crooks is many thefts involving medical marijuana are never reported by the victims.

If a medical marijuana cultivation site were permitted in our rural neighborhood, it would be like putting up a neon sign inviting trouble into our neighborhood from both sides of the border. We are only four miles from the Mexican border. The County Sheriff’s Department has told us that with current staffing limitations, they don’t know how well they could respond to all the potential problems they anticipate we could see if medical marijuana is permitted in our rural community. I guarantee you, our concerns are legitimate. We would be at risk. “No pot plant here,” neighbor.

One of the best ways to think about what’s missing is to change your point of view so that you now become an advocate for the “other side.” In this case, try to view the argument from the perspective of someone who does not agree with the conclusion that is being advocated. What premises are missing or additional information is needed that would support an opposite conclusion? First, what is the conclusion? That is easy—we should not allow the legal sale of marijuana in this neighborhood. What data support the conclusion? There is the idea that crime will increase, but this point is muddied by the admitted fact that “Crime in general may not go up appreciably.” The author argues that criminals will target medical marijuana facilities because they are easy targets and the criminals can sell the stolen marijuana for “as much as $300 to $600 an ounce.” So far, seems good, but when you consider the issues from the perspective of what is not given as information, you often will arrive at a different conclusion.

What is missing from this argument? What about medical benefits that come from the medical use of marijuana such as relieving the intense nausea caused by chemotherapy? The author omitted all counterarguments about the benefits of allowing people to use marijuana for medical reasons. Is the analogy to putting up a neon sign inviting trouble a good one? Pharmacies have all sorts of drugs that can be sold illegally. Should they also be banned for similar reasons? What is being assumed by the reference to Mexico? Are the data provided accurate and unbiased? Does marijuana really sell for that much money? Did crime increase in other cities that allowed the use of medical marijuana? Overall how strong is this argument? Reasonable people will disagree on the importance of different types of data and what type of data are relevant; but in argument analysis, the focus is on the quality of the reasons and counter reasons, which moves the discussion away from appeals to emotions. We will not all think the same by using argument analysis, but we will think better.

Sound Arguments

A good argument is technically called a sound argument. An argument is sound when it meets the following criteria:

1. The premises are acceptable and consistent. (You may have to eliminate some premises so that the others are consistent.)

2. The premises are relevant to the conclusion and provide sufficient support for the conclusion.

3. Missing components have been considered and are judged to be consistent with the conclusion.

Satisfying each of these criteria is a matter of degree. Premises are usually acceptable on some continuum from unacceptable to totally acceptable. The nature of support that they provide for the conclusion also lies on some continuum from no support to complete support. Similarly, the missing components, especially counterarguments, may weaken the argument anywhere from completely to not at all. Because all of these assessments have to be combined to decide if an argument is sound, we usually think of soundness as ranging from unsound to completely sound. An argument is unsound if its premises are false, or if they are unrelated to the conclusion, or if a critical counterargument is missing. An argument is completely sound if the premises are acceptable and related to the conclusion in a way that guarantees the acceptability of the conclusion. Most real-life arguments fall somewhere between these two extremes. For this reason, conclusions are often preceded with probability terms like, “it is likely that” or “we can probably conclude that.” Here are some examples of different degrees of soundness:

Completely Sound Argument (premises are acceptable and related to the conclusion in a way that guarantees the conclusion):

All mothers are women who have (or had) children. Suzi is a woman who has a son. Therefore, Suzi is a mother.

Unsound arguments (either the premises are unacceptable or they are unrelated to the conclusion):

All fathers have given birth to a child. Norbert has a son. Therefore Norbert has given birth to a child. (premise is unacceptable)

Non Sequitur by Wiley Miller. Used with permission by Universal Press Syndicate.

Norbert has a son; therefore, Norbert also has a daughter. (premise is unrelated to the conclusion)

Don’t confuse the truth or acceptability of a conclusion with the soundness of an argument. A conclusion can be objectively true, even when the argument is unsound. The conclusion could be true for reasons that have nothing to do with the information stated in the argument. Here is an example of a conclusion that is objectively true embedded in an unsound argument.

The structure of the family has been changing rapidly, with more single parents now heading their own households. Consequently, the divorce rate has begun to level off and decline slightly.

The conclusion about the divorce rate is true (according to demographers), but the argument is unsound because the premise does not support the conclusion.

Complex issues rarely have one correct conclusion. More often, many conclusions are possible, and the task of analyzing an argument involves deciding which of two or more conclusions has the greater strength or support.

How to Analyze an Argument

1. The first step is to read or listen to the passage to determine if it contains an argument. Are there at least one premise and at least one conclusion? If not, no further analysis is needed.

2. Identify all the stated and unstated component parts: premises, conclusions, assumptions, qualifiers, and counterarguments.

3. Check the premises for acceptability and consistency. If all of the premises are unacceptable, stop there because the argument is unsound. If only some of the premises are unacceptable, eliminate them, and continue with the acceptable premises. If the premises are inconsistent with each other, decide if you can justifiably eliminate one or more. An argument cannot be sound if the premises are inconsistent or contradict each other, but you may be able to eliminate the contradiction.

4. Diagram the argument. Consider the strength of the support that each premise provides for the conclusion. Rate the strength of support as nonexistent, weak, medium, or strong. Look over the number of supporting premises. A large number of supporting premises can provide strong support for the conclusion in a convergent structure, even when separately each only provides weak support.

5. Consider the strength of counterarguments, assumptions, and qualifiers (stated or omitted) and omitted premises. Do they undermine the support provided by the premises or strengthen or weaken it?

6. Finally, come to a global determination of the soundness of the argument. Is it unsound, completely sound, or somewhere in between? If it is somewhere in between, is it weak, medium, or strong?

You may be thinking that analyzing arguments is a lot of work. You are absolutely right. Diagramming and evaluating complex arguments can be as demanding as a long proof in mathematics or comprehending a complex novel. I realize that few people will formally diagram an argument in real life; however, it is a powerful and useful tool for comprehending complex arguments. Practice with diagramming arguments will aid in the analysis of other arguments even when, for time or other reasons, actual diagramming is not feasible. It will help you distinguish between the components of an argument and make judgments about its strength. When the issue is important and complex, making a diagram of its structure can be well worth the time and effort required.

A Template for Writing Sound Arguments

The importance of being able to write a sound argument is recognized as a critical thinking task that is essential for success in college and in professional careers. Several different standardized examinations are requiring test-takers to write an argument as a means of assessing critical thinking and writing skills. At the present time, written arguments are required for everyone who takes the Graduate Record Examination, the selection test used for entry to most graduate schools in the United States, as well as the examination used for selection for entry into business schools. Here is a template for writing sound arguments.

The template is designed to help you organize your thinking on complex issues and be able to explain evidence on two or more sides of an issue, such as the evidence for and against evolutionary hypotheses of mate selection or for and against the idea that parents are important influences on their children. In completing this template, you will have to gather and assess evidence to determine the best conclusion or conclusions and not start with what you believe is true. You will need to consider both supporting and disconfirming evidence—an exercise that can help you avoid the confirmation bias. Here is an applied example:

Making Arguments Template

Example 1: Does violence on television have a negative influence on children’s behavior?

1. State your conclusion. (Although you may begin your formal writing here, be sure that the conclusion follows from your reasons.) As you work, this is the last part that is filled in, not the first.

2. Give three reasons (or some other number) that support your conclusion.

3. Rate each reason as weak, moderate, strong, or very strong.

Rating for a:

Rating for b:

Rating for c:

4. Give three counterarguments (or some other number) that weaken your conclusion. Rate how much each counterargument weakens the conclusion: little, moderate, much, or very much.

Rating for a:

Rating for b:

Rating for c:

5. List any qualifiers (limitations on the reasons for or against—for example some evidence may be restricted to early childhood).

6. List any assumptions.

7. Are your reasons and counterarguments directly related to your conclusion?

8. What is the overall strength of your argument: weak, moderate, strong, or very strong?

Now that you have completed this worksheet, rate the overall strength of your argument.

Once the template is completed, the writing will be the easy part because you already know what you want to say and have listed your reasons and considered the strength of your argument. (If you are planning on taking any of the standardized admissions examinations that now require that you write an argument, this exercise should greatly improve your score.)

Reasoning and Rationalizing

People are irrational, short-sighted, destructive, ethnocentric, emotional, and easily misled by demagogues.

—Philip E. Tetlock (1994, p. 3)

When you evaluate arguments, you are also evaluating your own knowledge about the subject matter. There may be other counterarguments that are quite strong but that are unknown to you. Similarly, your ratings of the strength of the components may be biased in ways that support a conclusion that you favor. Nickerson (1986) makes an important distinction between reasoning and rationalizing. When we rationalize, we attend to information that favors a preferred conclusion. We may selectively gather information that supports a preferred conclusion or rate counterarguments as weak because they detract from a preferred conclusion. Rationalizing also influences the nature of the missing components that we supply to an existing argument. When we add to an argument, the information that we supply is information that is readily recalled. If you have already read the chapter on memory, then you are well aware of the many ways that memory can be biased. Rationalizing is usually not a deliberate process to distort the analysis of arguments, which makes it difficult to recognize and guard against. It is easier to recognize rationalizing when someone else is doing it. Perhaps the best you can do is realize that rationalization does occur and to try to be especially vigilant for rationalizing when you prefer a conclusion.

Just telling people that we tend to judge information that we favor as stronger than information that we oppose does not work to correct this bias. Is it any wonder why it is so difficult to get people to assess controversial issues in a fair-minded manner? Because we are not aware that we judge reasons in a way that supports what we believe to be true, it is very difficult to change the way we evaluate information. One successful attempt was accomplished by Koriat, Lichtenstein, and Fischhoff (1980). They required students to list reasons that support a conclusion and reasons that run counter to a conclusion (counterarguments) and to rate the strength of each. This should be familiar because they are the steps used in analyzing arguments. They found that students became more accurate in their assessments after this training in “giving reasons.” These results have been replicated in more recent studies in which the bias for information that confirms a prior belief was reduced by requiring people to provide reasons that did not support the preferred conclusion (Lenski, 2001; Flannelly & Flannelly, 2000). The authors of one of the studies summarized their research: “critical thinking skills of students should be fostered so the students come to appreciate the importance of weighting both positive and negative evidence” (Flannelly & Flannelly, 2000). These sorts of experimental results show that the giving and assessing of reasons can have beneficial results that improve the thinking process.

You can practice the giving of supporting and contradicting evidence and reasons for any controversial topic. Consider, for example, capital punishment. By filling in all four cells below and providing reasons for and against capital punishment, you will have to think about both sides of this controversial issue. It should help you to defend against my-side bias.

	Reasons that support the conclusion	Reasons that run counter to the conclusion
A. We should have capital punishment.	Reason 1: Strength of Reason 1: Reason 2: Strength of Reason 2:	Reason 1: Strength of Reason 1: Reason 2: Strength of Reason 2:
B. We should NOT have capital punishment.	Reason 1: Strength of Reason 1: Reason 2: Strength of Reason 2:	Reason 1: Strength of Reason 1: Reason 2: Strength of Reason 2:

How People Reach Different Conclusions from the Same Evidence

The problem may be less what politicians are actually saying, but rather how their words are heard and interpreted.

—Martin McKee and David Stuckler (para. 5, 2010)

The dramatic increase in the number of people diagnosed with diabetes is creating a health crisis of huge proportions. How do we understand the cause of diabetes, and what actions should we take (collectively) to stem the tide of increasing numbers? The idea that people prefer reasons and explanations that are consistent with their prior beliefs—confirmation bias—appears in many chapters in this book because of its strong and ubiquitous effect on how we think. In a study of the way confirmation bias operates, researchers (McKee & Stuckler, 2010) presented people with political affiliations ranging from liberal to conservative with information about diabetes. There were four conditions: (a) control condition in which no information about the cause of diabetes was presented; (b) a condition that discussed its genetic basis; (c) a condition that discussed the way individual life choices affect diabetes; and (d) a condition that discussed how social variables can affect diabetes. The authors found that people with more socially oriented political beliefs (i.e., Democrats) were more likely to believe that social determinants were important in causing the rise in diabetes, regardless of which version they read, and they were more likely to endorse restrictions on junk food as a way of reducing the diabetes problem than those with more individually oriented political beliefs (i.e., Republicans). In other words, the participants in this study used their preexisting biases to interpret new information and derived conclusions that were consistent with their preexisting political beliefs.

Persuasion and Propaganda

By the skillful and sustained use of propaganda, one can make people see even heaven as hell, or an extremely wretched life as paradise.

—Adolf Hitler (1889–1945)

Whenever you are confronted with an argument, keep in mind that the material you are reading or hearing has been written to persuade you to do something or to believe something. Much of the communication that you receive is concerned with getting you to act or think in a certain way. Pratkanis and Aronson (1992) define propaganda as “mass suggestion or influence through the manipulation of symbols and the psychology of the individual” (p. 9). This broad definition is applicable to a great variety of situations. Propaganda, like beauty, is often in the eye of the beholder. It does not require that the information be false or misleading, but it does at least imply less concern for truth or rigorous argument than the sort of arguments found in scholarly journals or presented by independent parties. It may distort the truth or alter evidence. Frequently, the information provided is charged with appeals to emotion rather than reason, and counterarguments are omitted or presented in a way that diminishes their effectiveness.

Arguments were most frequently used to persuade Nazis and others that millions of people should be slaughtered, but there were other propaganda techniques that Goebbels used, including visual images and threats of violence, for anyone who did not agree. Although other techniques are considered in more detail later in this chapter and in other chapters, I note here the particularly blatant ploy of showing pictures of Jews that were alternated with pictures of rats and roaches, so that viewers would come to associate certain facial features that are common in many Jews with disgusting rodents and bugs. This example was provided in Chapter 2 as a type of learning known as classical conditioning. These same sorts of techniques have been used to promote other types of equally horrific genocide. The propaganda used to justify slavery and lynchings in the United States, the slaughter of Cambodians in Asia, and the purges by Mao Tse-Tung in China and Stalin in the former Soviet Union show that propaganda has been used all over the world to encourage prejudice and killing. For examples, how did millions of Chinese, in the last century, believe that Mao was their “loving father” when he was responsible for the death of millions of Chinese? Why didn’t they stop to consider if the reasons they were given to support this Chinese holocaust (i.e., the Cultural Revolution) were not acceptable? Do you understand Hitler’s now infamous quote, “What luck for rulers that men do not think” (quoted in Byrne, 1988, p. 359)?

The Psychology of Reasons

Just because you are intelligent or have great knowledge does not mean you can think critically. A profound genius may have the most irrational of beliefs or the most unreasonable of opinions. Critical thinking is about how we use our intelligence and knowledge to reach objective and rationale viewpoints.

—Greg R. Haskins (2006, p. 2)

Warren Buffet is one of the richest men in the world. Forbes magazine listed his wealth in 2012 at $44 billion, so it is not surprising that people turn to him for advice about how to make money. Here is a sampling of his advice on how to get very, very rich. His first comment is a theme that you have read before, if you are reading the chapters in this book in order (Zweig, 2008; paras. 5–6): “I tell the students who come visit me that if you have more than 120 or 130 I.Q. points, you can afford to give the rest away. You do not need extraordinary intelligence to succeed as an investor. You need a philosophy and the ability to think independently.” He then goes to say: “You should be able to write down on a yellow sheet of paper, ‘I’m buying General Motors at $22, and GM has [566] million shares for a total market value of $13 billion, and GM is worth a lot more than $13 billion because ____________.” And if you can’t finish that sentence, then you don’t buy the stock. (Note that Buffett mentioned GM for illustrative purposes only.) So, his wisdom is that you don’t need extraordinary intelligence, but you do need to have good reasons for your investment choices. In other words, you need to support your conclusion with good evidence—you need to know how to make a good argument.

You probably think that irrelevant reasons for a conclusion would have no effect on how people evaluate a conclusion. It seems that this should be true because irrelevant reasons are, well, irrelevant. But, psychologically, irrelevant reasons often influence what we believe and how we act even though logically, they should not. A study of consumer decisions showed that irrelevant reasons in support of a product tend to weaken support for the product (Simonson, Nowlis, & Simonson, 1993). For example, suppose that you are a runner who is looking for good running shoes. As a salesperson, I tell you that Adibok brand is well known for their aerobic shoes, but they also make good running shoes. The fact that they are well known for their aerobic shoes should be irrelevant to the selection of running shoes, but it seems to work against this hypothetical brand. Consumers assume that if Adibok is good at making aerobic shoes, then it is less good at making running shoes. Thus, an irrelevant reason in support of this brand is psychologically converted into a reason against this brand.

Explaining as Knowing

“How do you know what you know?” (Kuhn, 2001). It seems that most people make judgments about their own knowledge by thinking about how well they can explain a phenomenon. For example, in studies of how jurors decide on the guilt or innocence of a defendant, researchers found that jurors weave a story about what might have happened at the scene of a crime and then decide how good that story is. This mode of knowing is often labeled “explaining.” Another way of knowing is to examine the strength of the evidence that supports or refutes a particular conclusion—this is known as argument analysis. Most people use “explanations” as the primary way of justifying claims (Rassin, Eerland, & Kuijpers, 2010). Consider this example:

Which is the stronger argument?

A.	Why do teenagers start smoking? Smith says it’s because they see ads that make smoking look attractive. A good-looking guy in neat clothes with a cigarette in his mouth is someone you would like to be like.
B.	Why do teenagers start smoking? Jones says it’s because they see ads that make smoking look attractive. When cigarette ads were banned from TV, smoking went down. (Kuhn, 2001, p. 4)

Answer A provides an explanation that links smoking and teens in a way that most people think “makes sense.” Answer B provides data, albeit limited, that links smoking and advertisements. The alternative that provides evidence for the relationship is stronger than the one that merely explains, even though many people prefer the explanation. There are many plausible explanations that could be generated, and without evidence (i.e., data) there is no good way to choose between them. Far too many people are very confident in their knowledge of something and very wrong. Think about your own understanding. How do you know about the nature of the world? This is not meant to be an idle navel-gazing question. If you can develop the disposition to look for evidence instead of relying on an explanation that “just seems right,” you will make large gains in critical thinking.

It is important to understand that people are quite confident in their knowledge because it makes sense to them, but “making sense” is a poor measure of the quality of your knowing. Sometimes, it is difficult to understand why data should be preferable to explanation. Consider these two examples: (1) During World War II, many Germans refused to believe that the German army burned an entire village in Poland as they were retreating from the Soviet front. They refused to believe it because the massacre did not make sense. Why should the German troops slaughter innocent people in Poland? In fact, historical records (eye witness accounts, physical evidence, written accounts, etc.) clearly show that this is what happened—the village was destroyed by frustrated German troops who were seeking revenge for their humiliating loss. The evidence is more compelling than the “make sense” explanation. It is important that we learn to value evidence when formulating conclusions. The use of data is a critical part of critical thinking.

The preference for explanations over evidence is just one of many ways that thinking can “go wrong.” In the next section, we consider other common ways that thinking can go astray. Unsound reasoning techniques used for the purpose of persuasion are called fallacies. As you go through the list of fallacies presented in the next section, you can classify each as violating one or more of the criteria for sound arguments—(a) the premises are unacceptable, (b) the premises are unrelated to the conclusion or (c) are inconsistent, (d) the expert is not credible, or (e) important information is missing.

It is impossible to list every fallacy that has been employed to change how people think. The list would be too long to be useful, with only subtle differences between several of the techniques. Accordingly, only the most common and representative techniques are discussed. If you understand how fallacies work in general, you’ll be better prepared to recognize and defend against them. Toulmin, Rieke, and Janik (1979) call the ability to recognize fallacies “a kind of sensitivity training” because they train the reader to be sensitive to common tricks of persuasion.

Twenty-One Common Fallacies

1. Association Effects

One of the oldest principles in psychology is the notion that if two events occur close together in time and/or space, the mind will form an association between them. Thereafter, when one occurs, the other is expected to occur. This principle has become widely used in the political arena, especially to create guilt by association. Suppose you read in the newspaper that a violent mass murderer endorsed a presidential candidate. This endorsement would be detrimental to the candidate, even if she did not desire it and did nothing to promote it.

A classic example of the propagandistic use of association came from a political speech (so many great examples in political speeches) in which a United States Congressman attacked the record of a gubernatorial candidate by stating that this candidate would not fight for the concerns of people who live in cities because he grew up “in a chicken shack on Duck Run” (quoted in Pickrell, 2010). The underlying argument was that this candidate was associated with rural areas (with negative imagery about rural areas) and therefore he would not care about the cities in his state. He may or may not care about the cities in his state, but is it reasonable to conclude that he would not because he grew up in a rural area? Are there any behaviors or statements that this candidate made that would support that conclusion? In this example, the answer is no. (Note also the use of the emotion laden phrase “chicken shack.”) Whenever you see examples of associations with no justifiable connection like this one, be wary of the rest of the message. It is likely to contain an appeal to your emotions rather than to your cognition.

Just as one can have guilt by association, it is also possible to have virtue by association. In this instance, the names or label attached to the person are “good” ones. Perhaps this is why certain political offices tend to run in families. People expected the Kennedy brothers to be similar as politicians because of their obvious association with each other or that the Bush children will be similar to their father, former president George Bush, Sr. This expectation is being passed onto the children and other relatives of political figures, many of whom are now involved in or considering political careers. Would you vote for or against an unknown Kennedy or Bush or some other politician simply because he or she is from the same family as a former politician?

A wary recipient of messages that rely on association will ask about the nature of the association. If a candidate is a leader of the Ku Klux Klan, then associating the doctrine of the Klan with this individual is reasonable. If, on the other hand, a friend of the candidate’s mother is a member of the Klan, the association is ludicrous.

Why would a supporter of a U.S. President (Obama) suggest that he stop using a nicotine gum that helps him stop smoking and go back to the real thing (Horwitz, 2008)? Can you guess the answer? Consider the demographics of smokers in America. Americans who earn between $24,000 and $36,000 a year are twice as likely to smoke cigarettes as those who earn more than $90,000 a year. According to Horwitz (2008, para. 5): “Bottom line: small-towners in the Rust Belt and Appalachia don’t cling to guns and religion so much as they do cigarettes.” By smoking in public, any candidate would be signaling that he is similar to this group of people and the similarity should help him at the polls and in general approval ratings. What do you think? Would a political candidate become more popular among voters who smoke if he also smoked publicly?

2. Arguments against the Person

Arguments against the person is the formal term for name calling or, in its Latin form, argumentum ad hominem. This form of persuasion or propaganda attacks the people who support a cause, and not the cause itself. From the standpoint of argument analysis, the personal attack is irrelevant to the conclusion. For example, the Nazis believed that the theory of relativity was wrong because its discoverer was a Jew named Albert Einstein. They never considered the evidence for or against the theory, just the religion of its originator. It is basically another form of the association effect. In this case, the association that is being made is between an idea and a person. The underlying principle is that if you don’t like the person who supports an idea, then you should also oppose the idea itself because the idea and the person are associated.

Suppose you were serving on a jury that had to decide which of two witnesses was telling the truth. Would you be swayed if one attorney told you to disregard one man’s testimony because he had been divorced twice? Presumably not, because the man’s marital status is irrelevant to the issue. Suppose you were told that one of the men had two previous convictions for lying to a jury. Would this argument against the person be relevant? I would think so. In this case, the information provided about the witness is relevant to the question of whether he is lying. Consider the strength and relevance of the argument and the purpose for which it is used, and don’t be misled by irrelevant attacks on the supporters or detractors of any position.

3. Appeals to Pity

Logical reasoning is set adrift on a sea of emotions.

—Hans Bluedorn (2008, para. 4)

An appeal to pity is easy to spot. Appeals to pity are often found in legal pleadings. A defendant’s poor background or turbulent home life will often be brought up during a trial. These appeals to pity have nothing to do with the question of whether a defendant is guilty or innocent, although they may be persuasive appeals for leniency in sentencing if the defendant is found guilty. Sometimes, students use appeals to pity when attempting to persuade a teacher to raise a low grade. The grade is assigned on the quality of the work that is done, but students sometimes argue that if they work hard (or some other sad reason), the work should be graded higher than comparable work by someone who did not work as hard.

4. Popularity and Testimonials

The popularity technique (also known as the “bandwagon”) relies on the need for conformity for its persuasive power. It is persuasive because it explains that everyone supports a position or buys a certain product. It is expected that the recipients of the message will adopt the belief or buy the product in order to feel as if she or he belongs to the groups mentioned. Implicitly, the message is, “if everyone is doing it, it must be right.”

A variation of the popularity technique is testimonials. Respected politicians or movie stars endorse a belief or product. It is believed that people will want to be similar to the people they respect, so they will choose to use the same deodorant or foot powder or support the same causes. The recipients of testimonials are expected to infer a conclusion from the information stated. It is expected that they will reason along these lines: Christie Brinkley is a gorgeous model with very few wrinkles. She uses the advertised beauty product. If I use this beauty product, like Christie Brinkley, I will have very few wrinkles. Of course, this conclusion does not follow from the first two sentences, but many people believe that it does or, at least implicitly, that it might. This fallacy is worsened when the testimonial is not even in the area in which the personality has expertise. Christie Brinkley also endorses a national newspaper. As far as I know, this is an area in which she has no expertise. She is not a credible expert in the area of journalistic quality. Yet, advertisements like these do sell products.

Calvin and Hobbes by Bill Watterson. Used with permission by Universal Press Syndicate.

Sometimes, however, the popularity technique and testimonials can be valid persuasive techniques. If, for example, all of the members of an unbiased expert panel established to study the effects of a drug decide that it is unsafe, I would consider this information relevant to the question of the drug’s safety because it passes the test of credibility. Similarly, if a leading educator endorses a reading text, this might properly have an impact on your evaluation of the text. Both of these examples presume that the “experts” have no personal motives for their endorsements—that is, they’re not being paid for saying these things, and their expertise is relevant to the position or product that they’re supporting. In this case, they are credible sources of information.

5. False Dichotomy

Don’t give him two sides to a question to worry him.

Give him one;

better yet, give him none!

—Ray Bradbury (Farenheit 451, 1950)

There are very few political or social decisions that have simple answers or that can be solved with simple choices. Yet, simple slogans are the prototype or most common and representative form of persuasive techniques. False dichotomy is sometimes called simplification or the Black or White Fallacy because readers are asked to decide between two positions, without allowing other alternatives or “gray areas” that would combine aspects of both choices.

The following question appeared in a questionnaire that was sent by an assemblyman to his constituents (“Assemblyman Montjoy Needs Your Views,” 2001):

Would you prefer that government cut spending or increase taxes?

Does this question bother you? It should. The answers to our fiscal problems are not this simple. You should ask where and how the cuts would be made and how and how much taxes would be increased. Perhaps “cuts” could be combined with small or temporary increases in taxes. Can you guess which answer the Assemblyman prefers? Given this choice, I believe that most people would prefer to “cut spending,” yet, for many, an entirely different response would result from a question that was worded differently.

It does seem that people engage in black or white thinking when they think about political issues. Bill O’Reilly (2006), a political commentator for Fox television, which is generally acknowledged as having a conservative bias, claims that there are two kinds of Americans: people like him, who love and cherish traditional values, and “secular progressives.” Dividing Americans into two types—good ones like me and bad ones who want to change America for the worse—is a good example of a false dichotomy. People vary along multiple dimensions and cannot be classified into one of two categories.

When you are faced with a false dichotomy or the simplification of a complex issue, do not ask yourself if the ideas are good or bad. Ask instead what is good about the ideas and what is bad about them. Consider other alternatives and combinations of ideas. Remember that one of the steps in analyzing arguments calls for supplying missing components—omitted premises, assumptions, qualifiers, and counterarguments.

6. Appeals to Pride or Snobbery

Speech was given to man to disguise his thoughts.

—Talleyrand (1754–1838; quoted in Macmillan, 1989, p. 544)

An appeal to pride or snobbery usually involves praise or flattery. A blatant and humorous example can be found in an advertisement that was mailed to me at home. (Notice that it begins with my name, a sure attention-getting technique.)

Dear Dr. Halpern,

You may just be the solution.

Here is the problem: How do you find the right subscribers for an extraordinary magazine that is about to be published—BUT, a magazine that isn’t for everyone? A magazine that is, in fact, for only a handful of bright, literate people, people who still in this world of instant communication love to sit down with a good book.

I would love to believe that the publishers know me personally and have written a magazine just for the kind of person I would like to be. The truth is, this letter went to tens of thousands of people whose names were bought as part of various mailing lists. Clearly, they are attempting to persuade me to purchase their magazine by appealing to my pride or snobbery. In its skeletal form, that message says that if there is a group that I want to belong to (in this case, bright, literate people, but it could be any group), then I should buy X (in this case a magazine).

7. Card Stacking or Suppressed Information

Card stacking or suppressed information operates as a persuasive technique by omitting information that supports the unfavored view. An automobile company recently compared the car they were advertising on television with a competitor. The advertisers stressed that their car got better mileage and cost less. What about the variables they omitted? Which car needed fewer repairs, had the more comfortable seating, or accelerated better? What about other makes of cars? When considering persuasive information, be sure to consider what has not been stated along with the stated claims. This is another example of the need to consider the missing components in an argument.

8. Circular Reasoning

In circular reasoning, the premise is simply a restatement of the conclusion. If you were to diagram the structure of this sort of argument, you would get a circle because the support for the conclusion is a restatement of the conclusion. Here is an example of circular reasoning:

We need to raise the speed limit because the current legal speed is too slow.

In this example, the reason given (current speed is too slow) is just another way of saying that we need to raise the speed limit. It does not support the conclusion. The conclusion would be supported with premises such as the assertion that there has been no change in the number or severity of automobile accidents with a lower speed limit or some similar statement that supports this conclusion.

9. Irrelevant Reasons

Arguments that utilize irrelevant reasons are fairly common. The Latin word for this sort of fallacy is non sequitur, which literally translates to “it doesn’t follow.” In other words, the reason or premise is unrelated to the conclusion. Of course, you recognize the importance of having relevant premises as one of the criteria for sound arguments. (If you do not, go back over the section of evaluating the quality of an argument.)

One example that comes to mind is a statement that a faculty member made at a curriculum committee meeting in which we were discussing whether we should require every student to take classes in a foreign language. The faculty member in favor of this proposal made this statement: “We should require every student to study a foreign language because it is important that we provide our students with a quality education.” Look carefully at the conclusion and the premise. Is the premise related to the conclusion? Everyone on the curriculum committee believed that all students should receive a quality education, but the issue was whether all students should be required to study a foreign language. There were no reasons given as to why studying a foreign language should be a required part of a quality education. The conclusion did not follow from the reason that was given.

10. Slippery Slope or Continuum

The slippery slope fallacy is best described by an example. One of the arguments against court-ordered desegregation of the schools was that if we allow the court to determine which public schools our children will attend, the court will also tell us whom we have to allow into our churches, whom we have to invite into our homes, and even whom we should marry. In this example, the action (court-ordered desegregation) lies on a continuum with the court ordering of whom we should marry at an extreme end. The argument being made is that if we allow the court to have jurisdiction over events at one end of the continuum, then it will take over the other events on the continuum. For this reason, this fallacy is called either slippery slope (once you start sliding down a slope you can’t stop) or the fallacy of continuum.

Most life events can be placed along a continuum. It does not necessarily follow that actions concerning some part of the continuum will also apply to other portions of the continuum. Let’s consider a second example. There are many arguments being made for and against same-sex marriages. One of the arguments against it is that if we allow same-sex couples to marry, we will then allow groups of people to marry, and then people can marry their animals, and so on. This sort of thinking does not take into account the fact that processes can be stopped, and it does not make a qualitative distinction between two people marrying, groups of people marrying, or marrying an animal. A more colorful name for this fallacy is “the camel’s nose in the tent.” It is based on the idea that if we let a camel stick its nose in the tent on a cold night, the rest of the camel will soon follow and you will have large smelly camel in your tent.

11. Straw Person

A straw person is weak and easy to knock down. With a straw person argument, a very weak form of an opponent’s argument is set up and then knocked down. It occurs when an opponent to a particular conclusion distorts the argument in support of the conclusion and substitutes one that is much weaker. For example, in a discussion about whether students should be evaluating their professors, one opponent to this idea offered this straw person argument: “You say that students’ evaluations of their professors should be included in decisions about which professors we should be promoting. Well, I certainly don’t think that the decision as to which professors get promoted should be made by students.” Notice how the original argument that “student evaluations should be included in the decision-making process” was changed to “students should not be deciding which professors get promoted.” The original argument was for student evaluations to be part of the criteria used in the decision-making process. This is not the same as having students actually make the decisions. In its changed form, the argument is easier to knock down, just like a straw person.

12. Part–Whole Fallacies

Part–whole fallacies are flip sides of the same error. A part–whole fallacy is made whenever a speaker or writer assumes that whatever is true of the whole is also true of all of its parts, and whatever is true of the parts is also true of the whole. Consider some outstanding, prestigious university. (Are you thinking about your own school?) As a whole, the student body is highly intelligent, but it would be wrong to believe that every student who attends that university is therefore highly intelligent.

13. Appeals to Ignorance

The peculiar thing about appeals to ignorance is that they can often be used to support two or more totally different conclusions. This should be a clue to you that the reasoning involved is fallacious. In appeals to ignorance, the premise involves something we don’t know. Our ignorance is being used to argue that since there is no evidence to support a conclusion, the conclusion must be wrong. Our ignorance of a topic can also be used to support a conclusion by stating that since there is no evidence that contradicts it, the conclusion must be right. I have heard both sides argue this way in a debate on the existence of God. Believers have argued that since no one can prove that God doesn’t exist, He therefore must exist. Nonbelievers have argued that since no one can prove that God exists, He therefore doesn’t exist. The absence of evidence doesn’t support any conclusion. The absence of evidence for one conclusion is not evidence for another conclusion.

14. Weak and Inappropriate Analogies

The topic of analogies was presented in the chapter “The Relationship between Thought and Language.” It also appears later in the book in the chapters on problem solving and creativity. Analogies are a basic thinking skill. We use analogies whenever we encounter something new and try to understand it by reference to something we already know. Although analogies can be extremely useful aids to comprehension, they can also be misused. Two objects or events are analogous when they share certain properties. When we argue with analogies, we conclude that what is true of one object or event is true of the other.

15. Appeals to Authority

Despite the fact that most people say they take TV or Internet reports with a grain of salt, few actually do. There’s something deeply compelling about hearing a claim from an authoritative source; we all have a voice in the back of our heads that wants the new claim to be true, and this desire gets confirmed by the belief that the story wouldn’t have made it all the way to the TV news without having been pretty well substantiated. What are you going to do?

—Brian Dunning (2011, para. 5)

I already introduced this fallacy in an informal way earlier in this chapter when I discussed expert credibility. Much of what we know and believe is based on what we learn from authorities. The fallacy of appeals to authority occurs when the authority we use to support the premises in an argument is the wrong authority. If I wanted to sell you a stereo, it would be valid if I quoted from an article on stereos written by a professor of acoustics (who is an independent authority). It would be a fallacious appeal if I told you that Kobe Bryant (a basketball star) called it the best stereo system he had ever seen. Thus, the fallacy is not in appealing to an authority on a topic, but to appealing to someone who is not a credible authority.

16. Incomplete Comparisons

“More doctors agree that Dopeys can give you the fastest pain relief.” Advertisements like this one are so common, that it is almost impossible to open a magazine without seeing one. Two different comparisons are made in this statement and both are incomplete. Whenever you see comparative terms, ask yourself “more than what?”, “fastest compared to what?” Incomplete comparisons are missing the other half of the equation.

17. Knowing the Unknowable

Sometimes we are given information that is impossible to know. This is the fallacy of knowing the unknowable. Suppose you read in the newspapers that we need to increase the size of the police force because the number of unreported rapes has increased dramatically. A little alarm should go off when you read this: How can anyone know about the number of unre-ported rapes? I don’t doubt that many rapes are not reported to the police or that this is an important issue. What is at question is the increase or decrease in the number when the actual number is unknowable.

18. False Cause

The fallacy of false cause is discussed more completely in the chapter “Thinking as Hypothesis Testing”, but it is also important to discuss in the context of reasoning fallacies. The fallacy of false cause occurs whenever someone argues that because two events occur together, or one follows the other closely in time, that one caused the other to occur. For example, consider the finding that as the number of churches increases in a city, so does the number of prostitutes. It would be false to conclude that churches cause an increase in prostitution or that prostitutes cause more churches to be built. In fact, as the size of a city increases so does the number of churches and the number of prostitutes, as well as the number of schools, dry cleaners, volunteer agencies, and so on. Neither of them caused any of the others. They all resulted from a third factor—in this case, an increase in population. Of course, it is possible that one variable did cause the other to occur, but more than co-occurrence is needed to justify a causal claim.

19. Put Downs

Only a fool would endorse this candidate! No patriotic American would disagree! You’d have to be stupid to believe that! These are all examples of put downs (also known as belittling the opposition). An opposing viewpoint is belittled so that agreeing with it would put you in the class of people who are fools, or unpatriotic, or stupid. This technique is not so much a reasoning fallacy as it is an emotional appeal or dare.

20. Appeals to Tradition

“That’s the way we’ve always done it.” Anyone who has tried to change a policy has heard this sentence or its variant, “If it ain’t broke, don’t fix it.” In appeals to tradition, the unstated assumption is that what exists is best. It may be true that current policy is better than some suggested change, but it also may not be true. There is nothing inherent in the fact that “that’s the way we’ve always done it” that makes it a good or best way to accomplish an objective. One of the attitudes of a critical thinker that was presented in the first chapter is flexibility. Appeals to tradition deny the possibility that a different way may be an improvement.

21. False Charge of Fallacy

That’s a fallacy! It seems that after some people learn to recognize fallacious reasoning, they then label everything that anyone says as a fallacy (Levi, 1991). Not every statement is a fallacy. The idea of critical thinking is to develop an amiable skepticism, not a cynical view that everything and everyone is false. It is important to know when to accept some statements as acceptable as it is to know when and what to question.

Distinguishing between Opinion, Reasoned Judgment, and Fact

Compare the following three statements.

Lady Gaga is a great singer.

Lady Gaga is a great singer because she can sing a wider variety of songs than any other contemporary artist.

Lady Gaga is a great singer with several different songs at the top of the chart and albums that have gone platinum.

In the first example, I have expressed an opinion. It is a simple assertion of a preference. I like it; I think it is best. No reasons were given to support the evaluation. Opinion reflects how an individual or group has assessed a position or product—e.g., “Vote for Max Lake; he’s the best man for the job!”

The second example also expresses a preference, but in this example, the preference is supported a reason. I like X because Y. This is an example of reasoned judgment. Other examples of reasoned judgment are provided throughout the chapter.

The third statement concerns factual claims. Facts have a verifiable truth value—e.g., Gravel-Os breakfast cereal has 100% of the recommended daily requirement of iron. Although I cannot personally check the truth-value of these facts, a credible authority (e.g., the Food and Drug Administration) has verified these claims for me. Often, the distinction between fact, opinion, and reasoned judgment is a fine one. If we say that Gravel-Os is a good cereal because it has 100% of the recommended daily requirement of iron, this is a reasoned judgment based, in part, on the unstated assumption that it is good to eat cereals that contain 100% of the recommended daily requirement of iron. The distinction becomes even more difficult when you recall that opinions can serve as the premises (reasons) in an argument. Thus, when I say that Gravel-Os is a good cereal because I like its nutty taste, I have a reason to support my conclusion. If I were to add that Gravel-Os is a good cereal because I like its nutty taste and it supplies all of my iron needs for the day, the strength of my argument is increased.

“Pure” facts that are untainted by opinion are often hard to find. Take, for example, your daily newspaper. Although news reporters are obligated to provide readers with facts, their opinions certainly color what they report and how they report it. Compare the way two different newspapers cover the same story. One newspaper could make it the headline on page one, thus making it important news that will be read by many, whereas the other could place it in an inside section in smaller print, thus making sure that fewer people will read the story. Look at the words used to convey the same story.

Most news media (news magazines, newspapers, television news) are biased toward providing information that “sells.” The news media often treat complex issues in a very simplistic manner with a heavy emphasis on controversies because they are more interesting than agreements. The usual rules of scientific evidence and reasoning often are abandoned in the news media where deadlines determine the news you get and interest value can drive content. The distinction between fact and opinion is becoming increasingly difficult to discern. How much of reality television is real? The fuzzy distinction between the real and unreal gets even more difficult now that “virtual reality” computer programs are available and rival “real reality.” It is a brave, new world that we are entering—one that makes critical thinking more necessary than ever.

It has been said that there is never just one war fought. Each side has its own version, and rarely do they agree. Unfortunately, there is always fighting somewhere around the world so that you can verify this statement for yourself. It is not unusual for each side to claim that the other fired first, or for both sides to claim victory in a battle. Obviously, in the absence of verifiable truth, there is no way to know which, if either, side is presenting the facts. As before, the best way to assess the quality of the information provided is to consider the credibility of the reporter. I would prefer a report from an independent third party with first-hand and direct knowledge and appropriate credentials to a report from spokespersons from either of the sides involved in a dispute. It is now possible to get news from multiple sources, including Al Jazeera (an Arabic language news program that is broadcast in multiple languages, including English), BBC (British Broadcast Corporation), and many more. It is useful to see how they cover the same news story.

Evaluating Information on the Internet

A website hosted by the Mankato Area Chamber & Convention Bureau extolled the many attractions in this beautiful city in Minnesota, including whale watching on the Minnesota River (n.d.). Surprised? You should be because the web site was originally created by a professor at Mankato State University to highlight the importance of critically evaluation information found on the Internet. (I assume you figured out that there are no whales on the river in Minnesota.) We are far too trusting of the information we find while searching legitimate-looking web sites. There are many guides for evaluating information, whether it is on the Internet or in a book (even this one). Bell (2012) suggests that every reader ask these questions:

1. Does the author state the goals for the publication? (Is it meant to persuade, advocate, inform, or sell something?)

2. Is the author biased? (Is there only one point of view? Does the author acknowledge bias? Are there facts and arguments for all sides of controversial topics? Is the language meant to arouse emotions?)

3. Is the author’s affiliation reflected in the information? (Does the argument support the mission of the affiliation? Are there benefits to the organization if people agree with the arguments presented?)

4. Is the information valid and well-researched? (Are opinions disguised as facts? Are conclusions supported with evidence? Are the assumptions reasonable?)

Visual Arguments

He who controls images controls everything.

—Robert Townsend (quoted in Beilensen & Jackson, Eds., 1992, p. 15)

We are living in an increasingly visual society where we get more of our information from visual displays than from words. Television is a major source of information and entertainment for many people. The average television viewer will see approximately two million commercials by age 65 (Mitroff & Herr, 2007). The message in each is mostly the same—whatever your problem is (e.g., rough elbows, teeth that do not dazzle with sparkling whiteness, being overweight), you can buy a product that will solve it. Much of the persuasive message in television commercials is conveyed through the pictures that we see, often with the accompanying dialogue being of secondary importance. Images are also important in magazines, newspapers, video games, the Internet, and on billboards.

The effects of visual images are more difficult to gauge because they are often subtle. Consider a sample of cigarette advertisements. Smoking is linked to beauty, glamour, youth, health, and popularity. A popular theme in visual cigarette advertisements is horses and the “great” outdoors. We are shown beautiful, happy people smoking and enjoying the good life. The horses suggest ruggedness and an unrestrained independence—just the sort of person who won’t be swayed with facts that link smoking with many diseases. Careful market research pinpoints specific markets for cigarette smokers and designs images to appeal to market segments, for example, young women, with no more than a high school education, who wear jeans, and work at blue collar jobs. The images in these ads are very different from those targeted at more educated women, who are shown reading and talking while they smoke.

Visual images can be powerful determinants of public opinion and policy. I cannot forget the pictures of starving children in Somalia, which eloquently spoke of the dire need to send U.S. troops to assist with this disaster or the image of a dead U.S. serviceman being dragged through the dusty streets of Somalia. Which image moved the United States to promptly leave Somalia? What if the images had been different? Suppose that instead of the dead peacekeeper being dragged through the street, the media had shown pictures of Somalians receiving food and clean water—people who were alive because of the peacekeepers? The images we are shown have profound effects on how we think and feel.

Figure 5.2 shows some old propagandist images that were popular in Russia in the early and mid-20th century. Note the image of the fat, rich capitalist. His pig-like face and bloated body are deliberately unattractive, and his sea of gold depicts his solitary concern with material wealth. Look also at the Soviet Army recruiter with the outstretched, pointing finger, urging Russians to volunteer. Compare him to the military recruiting posters that were popular in the United States during the same time period, a time when people in the United States knew that “Uncle Sam wants you.”

Figure 5.2 Images of persuasion. The piglike man surrounded with his gold was designed to represent the capitalist. It was a common image during the years when Soviet Communists needed to keep the idea that “capitalism is bad” alive. By contrast, the Soviet recruiter has his arms open to welcome all to the great cause. He bears an uncanny similarity in pose and nonverbal gestures to the American recruiting poster where we were told that “Uncle Sam Wants You” (“Warning! Our Homes Are in Danger Now!” poster, General Motors Corporation, 1942, National Archives, Powers of Persuasion.)

Often an image can speak more persuasively for a point of view than even the most eloquent prose. The images in Figure 5.3 were all advertisements. You do not need to be able to read the words to understand the message. There is the gruesome death from cigarettes advertisement, the seductive child, the dangerous looking dark man, and two old favorites—doctors recommending cigarettes and the hard working wife who takes “pep” for vitamins. Cognitive psychologists know that we have very good picture memory—a fact that is exploited in these advertisements. Oftentimes we do not scrutinize the images that bombard us with the same care that we use for verbal arguments. Pay attention to the images you encounter throughout the day and consider how each is influencing what and how you think. These images are often used as nonverbal communication that reinforces stereotypes, and they are so ubiquitous that we often take them for granted. Look at and think about the images you see. Are some groups usually depicted in menial jobs on television or in advertisements? Who is used to display high fashion and who is depicted in warnings about criminal activity? It is only when you become consciously aware of the images you are viewing that you can think critically about the visual arguments you are receiving.

Figure 5.3 Visual images can make arguments. You don’t need to be able to read the language to recognize the gruesome face of death due to cigarettes. Other images show the use of stereotypes to sell something—the sexualization of children to sell products, doctors to sell cigarettes, “dark” men who are dangerous, and the oldie, but goodie image of the happy wife who takes “Pep” vitamins. (Anti-smoking advertisement appears courtesy of the Department of Health, the Government of the Hong Kong Special Administrative Region.)

How to Change Beliefs

We are constantly surrounded by individuals and groups who want to change what we think and how we act. Nearly every social interaction involves persuasion. Advertising agencies want us to buy whatever product they are selling; political candidates want our votes; the beef council wants us to eat more beef. The list is endless. Some of these beliefs and actions are beneficial, but others are not. One of the best ways to understand the dynamics of changing beliefs is to consider the issues from the perspective of someone who wants to change the beliefs of someone else. You can use this knowledge to change beliefs or to resist change. The following list is loosely adapted from a summary of the attitude change literature.

1. Provide a credible source for the information you are presenting. The source of information should be a person or agency with the necessary expertise in the field and who is independent with respect to the issue. Additional requirements for assessing the credibility of an information source are provided in this chapter.

2. Anticipate counterarguments, raise them, and provide counterexamples. This is a good technique when debating an issue before an audience. It can leave the opposition with few points to make. As you know, counterarguments weaken the support for a conclusion. This technique allows you to weaken the counterarguments.

3. Do not appear one-sided, especially when the audience may be predisposed to the opposite side. The willingness to use qualifiers and to consider counterarguments make your position appear more credible.

4. Be direct. Tell your audience what to believe. By explicitly stating the conclusion, you eliminate the possibility that the audience will arrive at a different conclusion or not “see” the support for the conclusion that you are advocating.

5. Encourage discussion and public commitment. These variables have not been discussed in this chapter, although they appear in other places in the book. The discussion allows the audience to generate reasons and to “own” them or view them as reasons that they provided. Public commitment is a powerful motivator. If someone signs a document or speaks in favor of a position, a host of psychological mechanisms are brought into play. It is a kind of a promise to believe or act in a certain way. A restaurant owner in Los Angeles has borrowed the technique of commitment. A big problem for many restaurants is the large number of people who make reservations and then neither show up for the reservation nor call to cancel it. In the past, when customers called to make reservations, they were told, “Please call if you have to cancel the reservations.” Now, the person who takes the reservation asks, “Will you please call if you have to cancel the reservations?” The customer needs to make a commitment to call—and the simple act of committing seems to make a difference. The number of customers who do not cancel their reservations when they are not keeping them is greatly reduced. What a difference two words can make.

6. Repeat the conclusion and the reasons that support the conclusion several times. People prefer positions that are familiar to them. You can make the same points in several different ways. Repetition is a useful aid in recall. Thus, reasons that are easily remembered (i.e., more available in memory) are more readily used to assess the strength of an argument. (The potent effects of repeated exposure are presented in the chapter on decision making.)

7. Provide as many reasons to support the conclusion as is feasible. As you already know, one way to increase the strength of an argument is by increasing the number of reasons that support it.

8. The message should be easy to comprehend. People are negatively affected by messages they find incomprehensible.

9. You could use any of the 21 common fallacies presented in this chapter. But be wary, they are examples of unsound reasoning. If you want to persuade someone, your reasoning should be sound. Shoddy reasoning is detectable, and if detected, it could (and should) destroy your credibility.

10. Use vivid images that will be difficult to forget and be sure that they make your point.

Chapter Summary

• An argument is an attempt to convince the reader (or listener) that a particular conclusion is true based on the reasons presented.

• All arguments must have at least one conclusion and one premise (reason). Arguments may also have assumptions, qualifiers, and counterarguments.

• Arguments have structures that can be identified and diagrammed.

• Sound (good) arguments meet three criteria: the premises are acceptable and consistent; the premises provide support for the conclusion by being relevant to the conclusion and are sufficiently strong; and missing components of the argument (e.g., assumptions, counterarguments, qualifiers, premises, and rival conclusions) have been considered.

• When analyzing the strength of an argument, the amount of support each premise supplies to the conclusion is weighed along with the negative effects of counterarguments. Missing components are made explicit and are considered along with the stated components.

• It is often necessary to assess the credibility of a source of information when deciding on the acceptability of a premise. There are important differences between experts for issues of fact and experts for issues of value.

• People like to believe that their beliefs and actions are “reasoned”; however, most people are not sensitive to poor or weak reasoning. Unfortunately, there is a general preference for explanations that “make sense” over conclusions that are justified by available data. Critical thinkers need to understand the importance of data and value data-based conclusions.

• There is a widespread bias to assign greater importance to reasons that support a conclusion that we favor (my-side bias) than to reasons that run counter to a conclusion that we favor. This bias can be reduced by listing reasons and counterarguments and consciously deciding how strongly they support or run counter to a conclusion.

• A critical part of the analysis of arguments is the consideration of missing parts and misleading statements.

• Arguments of all sorts have been used to justify genocide and other versions of “ethnic cleansing.” The techniques presented here could prevent future horrors if people are willing to invest the time and hard work in analyzing arguments.

• Twenty-one common techniques of propaganda were presented. Most can be categorized as types of unsound reasoning in which emotional appeals are often substituted for reasons.

• A distinction was made between the terms “opinion,” “reasoned judgment,” and “fact.” An opinion is an unsupported statement of preference. Reasoned judgment is a belief that is based on the consideration of premises that support that belief. Facts have a verifiable true value. It is often difficult to discern the difference between these terms in real-life settings.

• Visual images are used to persuade. Strong images that are difficult to forget can support or refute a conclusion. They usually appeal to emotions and often use stereotypes to support the implied conclusion.

• The beliefs of others can be changed with sound and unsound reasoning. Beware of attempts to manipulate your beliefs with shoddy reasoning techniques.

The following skills for analyzing arguments were presented in this chapter. If you are unsure about how to use any of these skills, be sure to reread the section in which it is discussed.

• identifying arguments

• diagramming the structure of an argument

• evaluating premises for their acceptability

• examining the credibility of an information source

• determining the consistency, relevance to the conclusion, and adequacy in the way premises support a conclusion

• remembering to consider missing components by assuming a different perspective

• assessing the overall strength of an argument

• recognizing, labeling, and explaining what is wrong with each of the 21 fallacies that were presented

• recognizing differences between opinion, reasoned judgment, and fact

• understanding how visual arguments can be effective

• judging your own arguments for their strength.

Terms to Know

Check your understanding of the concepts presented in this chapter by reviewing their definitions. If you find that you are having difficulty with any term, be sure to reread the section where it is discussed.

Argument. An argument consists of one or more statements that are used to provide support for a conclusion.

Conclusion. The belief or statement that the writer or speaker is advocating. It is what the speaker wants you to do or believe.

Reasons. The bases for believing that a conclusion is true or probably true. Note: This word may be singular or plural as there may be one or more reasons for a conclusion. When we reason (singular only), we are following rules for determining whether an argument is sound.

Premises. The formal term for the statements that support a conclusion.

Premise Indicators. Key words that often (but not always) signal that the statement or statements that follow them are premises.

Conclusion Indicators. Key words that often (but not always) signal that the statement or statements that follow them are conclusions.

Assumptions. In an argument, an assumption is a statement for which no proof or evidence is offered. They may be stated or implied.

Subarguments. Arguments that are used to build the main argument in an extended passage.

Main Point. The principal argument in an extended passage.

Qualifier. A constraint or restriction on the conclusion.

Counterargument. Statements that refute or weaken a particular conclusion.

Statement. A phrase or sentence for which it makes sense to ask the question, “Is it true or false?” Questions, commands, and exclamations are not statements.

Convergent Structures. A type of argument in which two or more premises support the same conclusion.

Chained (or Linked) Structures. Argument types in which the conclusion of one subargument becomes the premise of a second argument.

Acceptable. A standard for assessing the quality of a premise. A premise is acceptable when it is true or when we can reasonably believe that it is true.

Consistent. A standard for assessing the quality of an argument. When the premises that support a conclusion are not contradictory, they are consistent.

Adequate Grounds. A standard for assessing the quality of an argument. Occurs when the premises provide good support for a conclusion.

Sound Argument. Meets three criteria: 1. Acceptable and consistent premises; 2. Premises are relevant and provide sufficient support for the conclusion; 3. Missing components are considered and evaluated.

Rationalizing. A biased analysis of an argument so that a preferred conclusion will be judged as acceptable or a nonpreferred conclusion will be judged as unacceptable. The process of rationalizing is usually not conscious.

Propaganda. Information presented by proselytizers of a doctrine or belief. It may distort the truth, alter evidence, and appeal to emotions. The objective is to get the reader or listener to endorse the belief.

Fallacies. Unsound reasoning techniques that are used to change how people think.

Guilt by Association. The fallacy of associating a position or person with an undesirable position or person in order to create a negative impression.

Virtue by Association. The fallacy of associating a position or person with a desirable position or person in order to create a favorable impression. Compare with guilt by association.

Arguments Against the Person. A form of propaganda that attacks the people who support a cause and not the cause itself.

Appeals to Pity. A fallacy that asks for your compassion instead of appealing to your reason.

Popularity. A fallacy in which the only reason for the conclusion is that it is endorsed by “everyone.”

Testimonials. An appeal in which the sole support for a conclusion is someone’s unsupported opinion.

False Dichotomy. An argument in which two possible conclusions or courses of action are presented when there are multiple other possibilities. (Also known as Black or White Fallacy.)

Card Stacking. A fallacy that omits important information that might support an unfavored view.

Appeals to Pride or Snobbery. The use of praise or flattery to get its recipient to agree with a position.

Circular Reasoning. An argument structure in which the premise is a restatement of the conclusion. If diagrammed, it would be a circle.

Slippery Slope. Counterargument for a conclusion in which the premise consists of the idea that because certain events lie along some continuum, it is not possible to take an action without affecting all the events on the continuum.

Continuum. Fallacy of the Continuum is the same as Slippery Slope.

Straw Person. A type of fallacy in which an opponent to a conclusion distorts the argument that supports the conclusion by substituting a weaker argument.

Appeals to Ignorance. An argument in which the premise involves something that is unknown.

Knowing the Unknowable. Fallacy in which numbers are provided for events that cannot be quantified.

False Cause. Fallacy in which one event is said to have caused the other because they occur together.

Put Downs. Belittling an opposing point of view so that it would be difficult for a listener to agree with it.

Appeals to Tradition. A fallacy that utilizes the reason that what already exists is best.