Critical Thinking

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Critical Thinking

• Chapter 1

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Your Instructor

• John Provost
• 831-402-7374
• jprovost_at_mpc.edu

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Agenda

• Introduction and Story
• Syllabus and Texts
• Homework
• Start Lecture 1

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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

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What is Critical Thinking?

• Critical thinking is about helping ourselves and
  others. Why?

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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.

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Two primary skills required

• Read carefully
• Listen closely

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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?

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Mistakes Fallacies

• Fallacy of composition We dont spend that much
  on military salaries. After all, who ever heard
  of anyone getting rich in the Army? In other
  words, we dont spend that much on service
  personnel individually therefore we dont spend
  much on them as a group.

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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.

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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.

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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).

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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
  oddballs proposal, but it does not follow that
  it is an oddball proposal! See?

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Mistakes Straw Man

• The straw man fallacy happens when you refute a
  position or claim by distorting or
  oversimplifying or misrepresenting it. Lets 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 doesnt mean I
  do.

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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

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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.

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To think critically, then, we need to know

• 2. What considerations are relevant to that issue
• 3. Whether the reasoning underlying the persons
  claim is good reasoning
• 4. And whether, everything considered, we should
  accept, reject, or suspend judgment on what the
  person has claimed

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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.

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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.

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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.

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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.

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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.

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Recognizing Arguments

• An argument always has a conclusion. Always.
  Without a conclusion, a bunch of words isnt an
  argument. But an argument also needs at least one
  premise. Without a premise you have no support
  for the conclusion and so you dont have an
  argument.

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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).

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A premise

• A premise is the claim or claims in an argument
  that provide the reasons for believing the
  conclusion.

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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.

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Factual Issues Versus Nonfactual Issues

• Is your dad or uncle older? That is a factual
  issue.
• Asking whether it is better to be your dads age
  or your uncles age is a nonfactual issue.

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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!

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Factual Claims

• An issue is factual if there are established
  methods for settling it.
• Factual claims can be determined, while opinions
  cannot be determined.

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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.

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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.

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Opinion and Pure Opinion

• An opinion is someones belief on an issue, or
  someones 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,
  someones 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 cant
  have a pure opinion about it as if they were any
  age you decide they should be.

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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.

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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.

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Relevance, Rhetoric, and Keeping a Clear Head

• Critical thinking involves recognizing the
  rhetorical force of language and trying not to be
  influenced by it.

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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 persons position is.

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Conclusion

• It helps you know what considerations are
  relevant to that issue
• And whether the reasoning underlying the persons
  claim is good reasoning.

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Conclusion

• It helps you know what considerations are
  relevant to that issue
• And whether the reasoning underlying the persons
  claim is good reasoning.
• It helps you determine whether, everything
  considered, you should accept, reject, or suspend
  judgment on what the person claims.

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Conclusion

• These skills require you to be levelheaded and
  objective and uninfluenced by extraneous factors.

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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.

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Exercises

• 1. Meat grilled over hickory coals tastes better
  than meat grilled over mesquite.

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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.

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Exercises

• 2. I read in the newspaper that meat grilled over
  hickory coals tastes better than meat grilled
  over mesquite.

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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.

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Exercises

• 3. The air in Cleveland smells better than it did
  five years ago.

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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.

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Exercises

• 4. There are fewer hydrocarbons in the air in
  Cleveland than there were five years ago.

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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.

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Exercises

• 5. The air in Cleveland is lower in hydrocarbons
  because there is less automobile emission than
  there was five years ago.

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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.

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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.

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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 didnt. Intelligent opinions on this issue may
  differ, but that doesnt make it any less
  factual.

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Exercises

• Determine whether each of the following passages
  is (or contains) an argument.

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Exercises

• 1. Will a beverage begin to cool more quickly in
  the freezer or in the regular part of the
  refrigerator? Well, of course itll cool faster
  in the freezer! There are lots of people who
  dont understand anything at all about physics
  and who think things may begin to cool faster in
  the fridge. But theyre sadly mistaken.

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Exercises

• 1. Will a beverage begin to cool more quickly in
  the freezer or in the regular part of the
  refrigerator? Well, of course itll cool faster
  in the freezer! There are lots of people who
  dont understand anything at all about physics
  and who think things may begin to cool faster in
  the fridge. But theyre sadly mistaken.
• Clearly, our speaker has an opinion on then
  subject, but no argument is given.

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Exercises

• 2. Its 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

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Exercises

• 2. Its 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.

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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 hes Elvis is nuts.

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

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Exercises

• 4. Youd better not pet that dog. She looks
  friendly, but shes been known to bite.

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Exercises

• 4. Youd better not pet that dog. She looks
  friendly, but shes been known to bite.
• Argument

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Exercises

• Which speakers give arguments for their positions?

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Exercises

• larry Before we go to Hawaii, lets go to a
  tanning salon and get a tan. Then we wont look
  like we just got off the plane, plus we wont get
  sunburned while were over there.
• laurie I dont know . . . I read that those
  places can be dangerous. And did you ever check
  out how much they cost? Lets let it go.

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Exercises

• larry Before we go to Hawaii, lets go to a
  tanning salon and get a tan. Then we wont look
  like we just got off the plane, plus we wont get
  sunburned while were over there.
• laurie I dont know . . . I read that those
  places can be dangerous. And did you ever check
  out how much they cost? Lets let it go.
• Larry and Laurie are both giving arguments.

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Exercises

• 2. she When you think about it, theres every
  reason why women soldiers shouldnt serve in
  combat.
• he Well, I dont think anyone should have to
  serve in combat. I wouldnt make anyone serve who
  doesnt want to.

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Exercises

• 2. she When you think about it, theres every
  reason why women soldiers shouldnt serve in
  combat.
• he Well, I dont think anyone should have to
  serve in combat. I wouldnt make anyone serve who
  doesnt want to.
• Neither speaker is giving an argument.

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Exercises

• 3. student a My family is very conservative. I
  dont think theyd 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.

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Exercises

• 3. student a My family is very conservative. I
  dont think theyd 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.

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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 were
  worth. There should be limits on the amounts
  insurance companies may be required to pay out on
  claims.
• attorney Limits? Doesnt sound like a good idea
  to me. What if someones medical expenses exceed
  those limits? Do we just say, Sorry, Charlie?

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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 were
  worth. There should be limits on the amounts
  insurance companies may be required to pay out on
  claims.
• attorney Limits? Doesnt sound like a good idea
  to me. What if someones medical expenses exceed
  those limits? Do we just say, Sorry, Charlie?
• Only Attorney is giving an argument.

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Exercises

• Determine which of the following passages contain
  an argument, and, for any that do, identify the
  arguments final conclusion.

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Exercises

• 1. Your jacket looks a little tattered, there,
  Houston. Time to get a new one, Id say.

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Exercises

• 1. Your jacket looks a little tattered, there,
  Houston. Time to get a new one, Id say.
• Argument. Conclusion Time to get a new jacket.

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Exercises

• 2. I seriously doubt many people want to
  connect up their TV to the Internet. For one
  thing, when people watch TV they dont want more
  information. For another thing, even if they did,
  they wouldnt be interested in having to do
  something to get it. They just want to sit back
  and let the TV tell them whats happening.

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Exercises

• 2. I seriously doubt many people want to
  connect up their TV to the Internet. For one
  thing, when people watch TV they dont want more
  information. For another thing, even if they did,
  they wouldnt be interested in having to do
  something to get it. They just want to sit back
  and let the TV tell them whats happening.
• Argument. Conclusion It is doubtful many
  people want to connect their TV to the Internet.

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Exercises

• 3. Heres 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.

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Exercises

• 3. Heres 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

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Exercises

• 4. Pretzels are pretty good for a snack food.
  But its wise to keep in mind that they are high
  in sodium, at least if you eat the salted kind.

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Exercises

• 4. Pretzels are pretty good for a snack food.
  But its wise to keep in mind that they are high
  in sodium, at least if you eat the salted kind.
• No argument

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Exercises

• Identify the passages that contain arguments in
  those that do, identify the main issue.

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Exercises

• 1. Its 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.

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Exercises

• 1. Its 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.

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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?
• LifeHow Did It Get Here? By Evolution or by
  Creation?

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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?
• LifeHow Did It Get Here? By Evolution or by
  Creation?
• No argument.

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Exercises

• 3. It is indeed said that the Japanese work
  more than 2,000 hours a year, but this is not so.
  At Sonyand at Sanyo or Matsushitathe total is
  somewhere between 1,800 and 1,900 hours.
• Akio Morita, chairman of Sony

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Exercises

• 3. It is indeed said that the Japanese work
  more than 2,000 hours a year, but this is not so.
  At Sonyand at Sanyo or Matsushitathe 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