Critical Thinking

Chapter 1

Your Instructor

John Provost

831-402-7374

jprovost@mpc.edu

Agenda Introduction and Story Syllabus and Texts Homework Start Lecture 1

Introduction: Why Study Critical Thinking?

“You can fool all of the people all of the time if the advertising

budget is big enough.” Ed Rollins, Republican campaign adviser

What is Critical Thinking? Critical thinking is about helping

ourselves and others. Why?

What is Critical Thinking?

“Critical thinking includes a variety of deliberative processes aimed at making wise decisions about what to believe and do, processes that center on evaluation of arguments but include much more.”

Two primary skills required: Read carefully Listen closely

Mistakes: Ambiguity Secretaries make more money than

physicians. What does this mean? She saw the farmer with binoculars.

Who had the binoculars? I know a little Greek. The language or a

person?

Mistakes: Fallacies Fallacy of composition: “We don’t spend

that much on military salaries. After all, who ever heard of anyone getting rich in the Army?” In other words, we don’t spend that much on service personnel individually; therefore we don’t spend much on them as a group.

Mistakes: Fallacies Fallacy of division: “Congress is

incompetent. Therefore, Congressman Benton is incompetent.” What holds true of a group does not necessarily hold true for all the individuals in that group.

Mistakes: Vague Claims “He is old.” Compared to what? Old is a

matter of context. Old for first grade? Old in general? The vagueness of a claim is a matter of degree.

Mistakes: A Red Herring When a person brings a topic into a

conversation that distracts from the original point, especially if the new topic is introduced in order to distract, the person is said to have introduced a red herring (see pages 168-169).

Mistakes: Ad Hominem We commit the ad hominem fallacy

when we think that considerations about a person “refute” his or her assertions.

Example: A proposal made by an oddball is an oddball’s proposal, but it does not follow that it is an oddball proposal! See?

Mistakes: Straw Man The straw man fallacy happens when you

“refute” a position or claim by distorting or oversimplifying or misrepresenting it. Let’s say Mrs. Herrington announces it is time to clean the attic. Mr. Herrington groans and says, “What, again? Do we have to clean it out everyday?” She responds: “Just because you think we should keep every last piece of junk forever doesn’t mean I do.”

Basic Critical Thinking Skills

When we take a position on an issue, we assert or claim something. The claim and thinking on which it is based are subject to rational evaluation. When we do that evaluating, we are thinking critically. To think critically, then, we need to know five things:

To think critically, then, we need to know: 1. When someone (including ourselves)

is taking a position on an issue, what that issue is, and what the person is claiming their position is on that issue.

To think critically, then, we need to know: 2. What considerations are relevant to

that issue 3. Whether the reasoning underlying the

person’s claim is good reasoning 4. And whether, everything considered,

we should accept, reject, or suspend judgment on what the person has claimed

To think critically, then, we need to know: Finally, 5. Doing all this requires us to

be levelheaded and objective and not influenced by extraneous factors.

Issues: What is an issue? It is something we have a question

about. A key word is “whether.” An issue is what is raised when you

consider whether a claim is true.

Arguments: What is an argument? Let us define an argument as an

attempt to support a claim or assertion by providing a reason or reasons for accepting it.

What is a claim? A claim is a statement that is either true

or false. The claim that is supported is called the conclusion of the argument, and the claim or claims that provide support are called the premises.

Arguments and Explanations An argument attempts to prove that

some claim is true, while an explanation attempts to specify how something works or what caused it or brought it about. Arguing that a dog has fleas is quite different from explaining how it came to have fleas. Explanations and arguments are different things.

Recognizing Arguments An argument always has a conclusion.

Always. Without a conclusion, a bunch of words isn’t an argument. But an argument also needs at least one premise. Without a premise you have no support for the conclusion and so you don’t have an argument.

An Explanation An explanation is a claim or set of

claims intended to make another claim, object, event, or state of affairs intelligible (but not true or false).

A premise A premise is the claim or claims in an

argument that provide the reasons for believing the conclusion.

Identifying Issues Before you can really recognize an

argument you have to know what the issues are.

An important clue to what the issue is will be to look for the conclusions. The conclusion that is presented refers to the issue being addressed.

Factual Issues Versus Nonfactual Issues Is your dad or uncle older? That is a

factual issue. Asking whether it is better to be your

dad’s age or your uncle’s age is a nonfactual issue.

Factual Claims A factual claim is simply a claim,

whether true or false, that states a position on a factual issue. But this is where it can be confusing.

Saying a claim is factual is not equivalent to saying it is true!

Factual Claims An issue is factual if there are

established methods for settling it.

Factual claims can be determined, while opinions cannot be determined.

Facts and Factual Matters A fact is a true claim. A factual issue is

an issue concerning a fact. The right answer about a factual issue will be a fact, whether we know that fact yet or not.

Subjectivism and Relativism Subjectivism is the idea that, just as two

people can disagree and yet both be “correct” on a nonfactual issue, they can both be correct in their differing opinions on the same factual issues.

Relativism is the parallel idea that two different cultures can be correct in their differing opinions on the same factual issues.

Opinion and Pure Opinion An opinion is someone’s belief on an issue, or

someone’s belief about a specific claim. That issue may well be a matter of fact. For the issue to be a matter of pure opinion, there must be no factual matter involved in it. For example, someone’s age is a factual issue. It can be determined. But you can still have an opinion on whether it is a good age or not. But you can’t have a pure opinion about it as if they were any age you decide they should be.

Relevance, Rhetoric, and Keeping a Clear Head One of the most serious and difficult

obstacles to clear thinking is the tendency to confuse extraneous and irrelevant considerations with the merits of a claim.

Another obstacle to clear thinking is paying more attention to the psychological force of an argument than its logical force.

Relevance, Rhetoric, and Keeping a Clear Head Some politicians, for example, rely on

the emotional associations of words to scare us, flatter us, and amuse us; to arose jealousy, desire, and disgust; to make good things sound bad and bad things sound good; and to confuse, mislead, and misinform us.

Relevance, Rhetoric, and Keeping a Clear Head Critical thinking involves recognizing the

rhetorical force of language and trying not to be influenced by it.

Conclusion Critical thinking helps you to know when

someone is taking a position on an issue

What that issue is And what the person is claiming relative

to that issue-that is, what the person’s position is.

Conclusion It helps you know what considerations

are relevant to that issue

And whether the reasoning underlying the person’s claim is good reasoning.

Conclusion It helps you know what considerations

are relevant to that issue And whether the reasoning underlying

the person’s claim is good reasoning. It helps you determine whether,

everything considered, you should accept, reject, or suspend judgment on what the person claims.

Conclusion These skills require you to be levelheaded

and objective and uninfluenced by extraneous factors.

Exercises For each of the following claims, decide

whether it states a subjective or a non-subjective (i.e. objective) claim. In cases where it may be difficult to decide, try to identify the source of the problem.

Exercises 1. Meat grilled over hickory coals tastes

better than meat grilled over mesquite.

Exercises Meat grilled over hickory coals tastes better

than meat grilled over mesquite.

Subjective. Notice that the claim passes the “contradiction test,” i.e. someone with an opposing viewpoint would not be wrong just because it contradicted the original claim. There is no ‘fact of the matter’ about how something tastes.

Exercises 2. I read in the newspaper that meat

grilled over hickory coals tastes better than meat grilled over mesquite.

Exercises 2. I read in the newspaper that meat grilled

over hickory coals tastes better than meat grilled over mesquite.

Non-subjective. The fact, of course, is only that the person read it in the newspaper.

Exercises 3. The air in Cleveland smells better

than it did five years ago.

Exercises 3. The air in Cleveland smells better

than it did five years ago.

Subjective. The qualitative sensation of how something smells to someone is a private, first-person, subjective experience.

Exercises 4. There are fewer hydrocarbons in

the air in Cleveland than there were five years ago.

Exercises 4. There are fewer hydrocarbons in

the air in Cleveland than there were five years ago.

Non-subjective. There is an objective fact of the matter that can be checked.

Exercises 5. The air in Cleveland is lower in

hydrocarbons because there is less automobile emission than there was five years ago.

Exercises 5. The air in Cleveland is lower in

hydrocarbons because there is less automobile emission than there was five years ago.

Non-subjective. This is an argument based on fact.

Exercises 6. There is less automobile emission

in Cleveland than there was five years ago because of the Clean Air Bill passed several years ago.

Exercises 6. There is less automobile emission in

Cleveland than there was five years ago because of the Clean Air Bill passed several years ago.

Non-subjective. Some will argue about this because of the difficulty of identifying the cause of lowered emissions. Nevertheless, either the change resulted from the Clean Air Bill, or it didn’t. Intelligent opinions on this issue may differ, but that doesn’t make it any less factual.

Exercises Determine whether each of the following

passages is (or contains) an argument.

Exercises1. Will a beverage begin to cool more quickly in the freezer or in the regular part of the refrigerator? Well, of course it’ll cool faster in the freezer! There are lots of people who don’t understand anything at all about physics and who think things may begin to cool faster in the fridge. But they’re sadly mistaken.

Exercises1. Will a beverage begin to cool more quickly in the freezer or in the regular part of the refrigerator? Well, of course it’ll cool faster in the freezer! There are lots of people who don’t understand anything at all about physics and who think things may begin to cool faster in the fridge. But they’re sadly mistaken.

Clearly, our speaker has an opinion on then subject, but no argument is given.

Exercises 2. It’s true that you can use

your television set to tell when a tornado is approaching. The reason is that tornadoes make an electrical disturbance in the 55 megahertz range, which is close to the band assigned to channel 2. If you know how to do it, you can get your set to pick up the current given off by the twister. So your television set can be your warning device that tells you when to dive for the cellar.

—Adapted from Cecil Adams, The Straight Dope

Exercises 2. It’s true that you can use

your television set to tell when a tornado is approaching. The reason is that tornadoes make an electrical disturbance in the 55 megahertz range, which is close to the band assigned to channel 2. If you know how to do it, you can get your set to pick up the current given off by the twister. So your television set can be your warning device that tells you when to dive for the cellar.

This passage might be taken as an explanation, but it is also an argument, since it is clearly designed to convince us that its main point is correct.

Exercises 3. Some of these

guys who do Elvis Presley imitations actually pay more for their outfits than Elvis paid for his! Anybody who would spend thousands just so he can spend a few minutes not fooling anybody into thinking he’s Elvis is nuts.

Exercises 3. Some of these

guys who do Elvis Presley imitations actually pay more for their outfits than Elvis paid for his! Anybody who would spend thousands just so he can spend a few minutes not fooling anybody into thinking he’s Elvis is nuts.

No argument. No connection is made between the cost of the outfits and the psychological deficiencies of Elvis impersonators.

Exercises 4. You’d better not

pet that dog. She looks friendly, but she’s been known to bite.

Exercises 4. You’d better not

pet that dog. She looks friendly, but she’s been known to bite.

Argument

Exercises Which speakers give arguments for

their positions?

Exercises larry: Before we go to Hawaii, let’s go to a

tanning salon and get a tan. Then we won’t look like we just got off the plane, plus we won’t get sunburned while we’re over there.

laurie: I don’t know . . . I read that those places can be dangerous. And did you ever check out how much they cost? Let’s let it go.

Exercises

larry: Before we go to Hawaii, let’s go to a tanning salon and get a tan. Then we won’t look like we just got off the plane, plus we won’t get sunburned while we’re over there.

laurie: I don’t know . . . I read that those places can be dangerous. And did you ever check out how much they cost? Let’s let it go.

Larry and Laurie are both giving arguments.

Exercises 2. she: When you think about it, there’s

every reason why women soldiers shouldn’t serve in combat.

he: Well, I don’t think anyone should have to serve in combat. I wouldn’t make anyone serve who doesn’t want to.

Exercises 2. she: When you think about it, there’s

every reason why women soldiers shouldn’t serve in combat.

he: Well, I don’t think anyone should have to serve in combat. I wouldn’t make anyone serve who doesn’t want to.

Neither speaker is giving an argument.

Exercises 3. student a: My family is very

conservative. I don’t think they’d like it if they found out that I was sharing an apartment with two males.

student b: But sooner or later you have to start living your own life.

Exercises 3. student a: My family is very

conservative. I don’t think they’d like it if they found out that I was sharing an apartment with two males.

student b: But sooner or later you have to start living your own life.

Both A and B are giving arguments. B is arguing for an unstated claim: You should share the apartment with the two males despite what your family would like.

Exercises 4. insurance exec: Insurance costs so

much because accident victims hire you lawyers to take us insurers to court and soak us for all we’re worth. There should be limits on the amounts insurance companies may be required to pay out on claims.

attorney: Limits? Doesn’t sound like a good idea to me. What if someone’s medical expenses exceed those limits? Do we just say, “Sorry, Charlie”?

Exercises 4. insurance exec: Insurance costs so much

because accident victims hire you lawyers to take us insurers to court and soak us for all we’re worth. There should be limits on the amounts insurance companies may be required to pay out on claims.

attorney: Limits? Doesn’t sound like a good idea to me. What if someone’s medical expenses exceed those limits? Do we just say, “Sorry, Charlie”?

Only Attorney is giving an argument.

Exercises Determine which of the following passages

contain an argument, and, for any that do, identify the argument’s final conclusion.

Exercises 1. “Your

jacket looks a little tattered, there, Houston. Time to get a new one, I’d say.”

Exercises 1. “Your jacket

looks a little tattered, there, Houston. Time to get a new one, I’d say.”

Argument. Conclusion: Time to get a new jacket.

Exercises 2. “I seriously doubt

many people want to connect up their TV to the Internet. For one thing, when people watch TV they don’t want more information. For another thing, even if they did, they wouldn’t be interested in having to do something to get it. They just want to sit back and let the TV tell them what’s happening.”

Exercises 2. “I seriously doubt

many people want to connect up their TV to the Internet. For one thing, when people watch TV they don’t want more information. For another thing, even if they did, they wouldn’t be interested in having to do something to get it. They just want to sit back and let the TV tell them what’s happening.”

Argument. Conclusion: It is doubtful many people want to connect their TV to the Internet.

Exercises 3. “Here’s how you

make chocolate milk. Warm up a cup of milk in the microwave for two minutes, then add two tablespoons of the chocolate. Stir it up, then stick it back in the microwave for another 30 seconds. Then enjoy it.”

Exercises 3. “Here’s how you

make chocolate milk. Warm up a cup of milk in the microwave for two minutes, then add two tablespoons of the chocolate. Stir it up, then stick it back in the microwave for another 30 seconds. Then enjoy it.”

No argument

Exercises 4. “Pretzels

are pretty good for a snack food. But it’s wise to keep in mind that they are high in sodium, at least if you eat the salted kind.”

Exercises 4. “Pretzels are

pretty good for a snack food. But it’s wise to keep in mind that they are high in sodium, at least if you eat the salted kind.”

No argument

Exercises Identify the passages that contain

arguments; in those that do, identify the main issue.

Exercises 1. It’s wise to let

states deny AFDC (Aid to Families with Dependent Children) benefits to unmarried kids under eighteen who live away from their parents. This would discourage thousands of these kids from having children of their own in order to get state-subsidized apartments.

Exercises 1. It’s wise to let

states deny AFDC (Aid to Families with Dependent Children) benefits to unmarried kids under eighteen who live away from their parents. This would discourage thousands of these kids from having children of their own in order to get state-subsidized apartments.

Argument. Issue: whether states should be allowed to deny AFDC benefits to youths under eighteen.

Exercises 5. “Those who

accept evolution contend that creation is not scientific; but can it be fairly said that the theory of evolution itself is truly scientific?”

—Life—How Did It Get Here? By Evolution or by Creation?

Exercises 2. “Those who

accept evolution contend that creation is not scientific; but can it be fairly said that the theory of evolution itself is truly scientific?”

—Life—How Did It Get Here? By Evolution or by Creation?

No argument.

Exercises 3. “It is indeed said

that the Japanese work more than 2,000 hours a year, but this is not so. At Sony—and at Sanyo or Matsushita—the total is somewhere between 1,800 and 1,900 hours.”

—Akio Morita, chairman of Sony

Exercises 3. “It is indeed said

that the Japanese work more than 2,000 hours a year, but this is not so. At Sony—and at Sanyo or Matsushita—the total is somewhere between 1,800 and 1,900 hours.”

—Akio Morita, chairman of Sony Argument. Issue:

whether the Japanese work more than 2,000 hours a year