Critical Thinking: Chapter 7

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Critical Thinking Chapter 7

• More Fallacies

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The Ad Hominem Fallacy

• The ad hominem fallacy rests on a confusion
  between the qualities of the person making a
  claim and the qualities of the claim itself. It
  is a rhetorical device that attacks the arguer
  instead of the argument.

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The Ad Hominem Fallacy

• A proposal made by an oddball is an oddballs
  proposal, but it does not follow that it is an
  oddball proposal.

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Personal Attack Ad Hominem

• A pattern of fallacious reasoning in which we
  refuse to accept anothers argument because there
  is something about the person we dont like or of
  which we disapprove.

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Personal Attack Ad Hominem

• Example Are you really going to believe her
  about librarians salaries not being excessive?
  Ill have you know she herself is a librarian, or
  dont you think that matters?

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The Inconsistency Ad Hominem

• A pattern of fallacious reasoning of the sort, I
  reject your claim because you act inconsistently
  with it yourself, or You cant make that claim
  now because you have in the past rejected it.

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The Inconsistency Ad Hominem

• The double standard argument is actually the
  inconsistency ad hominem.

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The Inconsistency Ad Hominem

• Example Did you ever notice how the people who
  favor abortion on demand are the same people who
  are against the death penalty?

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The Inconsistency Ad Hominem

• Example It really gripes me to see Bill Clinton
  talking about how cigarette smoking is a big
  contributor to public health costs. How can we
  trust him? Even he himself admits to smoking
  cigars!

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Circumstantial Ad Hominem

• Attempting to discredit a persons claim by
  referring to the persons circumstances.

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Circumstantial Ad Hominem

• Example Of course the Task Force on Crime is
  going to conclude that crime is on the way up. If
  they conclude its on the way down, theyd have
  to disband the task force, wouldnt they?

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Circumstantial Ad Hominem

• Example Of course that cant be a legitimate
  proposal. Theyre just trying to get the city
  council to pass a regulation that will stir up
  some business for them.

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Poisoning the Well

• Poisoning the well can be thought of as an ad
  hominem in advance.

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Poisoning the Well

• Example I wouldnt take a course from anyone in
  the Poly Sci department, if I were you. They are
  all anti-U.S., ultraliberal types, at least
  thats what I hear.

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Poisoning the Well

• ExampleThe next speaker is going to speak in
  favor of the idea. But she works for the gun
  lobby Dont even bother listening to what she
  says.

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Genetic Fallacy

• The genetic fallacy occurs when we try to refute
  a claim on the basis of its origin or history.
  Rejecting a proposition because it is supported
  by a group you dont like is a genetic fallacy.

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Genetic Fallacy

• Example You cant trust the arguments you find
  in that magazine. Its well known as a right-wing
  apologist for the wealthy.

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Genetic Fallacy

• Example I dont think postmodern expressionism
  is decent art. Its another style spawned by the
  East Coast art establishment, and, frankly, Im
  tired of that groups dictating to the rest of
  the art world.

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Positive Ad Hominem Fallacies

• If we automatically transfer the positive or
  favorable attributes of a person to what he or
  she says, that is a mistake in reasoning, as well.

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Positive Ad Hominem Fallacies

• Example The fact that in your view the NRA
  represents all that is good and proper does not
  enable you to infer that any specific proposal
  from the NRA is good and proper.

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Positive Ad Hominem Fallacies

• Example The fact that you think your mom is
  clever does not logically entitle you to conclude
  that any specific opinion of your moms is clever.

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The Straw Man Fallacy

• The straw man fallacy happens when you refute a
  position or claim by distorting or
  oversimplifying or misrepresenting it, all the
  while ignoring the persons actual position.

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The Straw Man Fallacy

• Example Gays in the military? Yes. Maybe you
  favor excluding everyone except for white
  Anglo-Saxon males with adolescent personalities,
  but not me.

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The Straw Man Fallacy

• Example Do I want the police department to take
  charge of writing parking tickets? You mean, do I
  want to get shot if I pull up next to a fire
  hydrant? What do you think?

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The False Dilemma Fallacy

• The false dilemma fallacy occurs when you limit
  considerations to only two alternatives although
  other alternatives may be available. A straw man
  is often used as part of a false dilemma.

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The False Dilemma Fallacy

• Example Overheard I dont know why Barbara
  wont go out with me. She must think Im too
  intense for her.

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The False Dilemma Fallacy

• Example Gays in the military? Either let them
  in, or keep out all minorities take your choice.
  Im for letting them in. the alternative is
  ridiculous.

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The Perfectionist Fallacy

• The perfectionist fallacy is a subspecies of
  false dilemma and a common rhetorical ploy. This
  principle downgrades policy X simply because it
  isnt perfect.

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The Perfectionist Fallacy

• Example No, I dont believe we ought to
  reinstate the death penalty in this state. Doing
  it isnt going to prevent all crime, and you know
  it.

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The Perfectionist Fallacy

• ExampleDont stay in the army. You were ROTC
  instead of going to one of the academies, and
  that means they might promote you for a while,
  but youll never get above lieutenant colonel.

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The Line-Drawing Fallacy

• Another version of the false dilemma is called
  the line-drawing fallacy, the fallacy of
  insisting that a line must be drawn at some point
  when in fact it is not necessary that such a line
  be drawn.

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The Line-Drawing Fallacy

• Example All this talk about secondhand smoke
  causing cancer, I just dont get it. How does it
  happen? WHEN does it happen? The first time you
  take a breath in a smoky room? The second time?
  You can never pin it down exactly.

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The Line-Drawing Fallacy

• ExampleWhat do you mean, I broke my curfew? All
  I did was walk to the curb. You wouldnt cite me
  if I stood on the porch, would you? And if Id
  just stepped off the porch, that wouldnt be any
  different. So whats so magical about the curb?

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Slippery Slope

• A form of fallacious reasoning in which it is
  assumed that some event must inevitably follow
  from some other, but in which no argument is made
  for the inevitability.

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Slippery Slope

• Example No, I dont believe in three strikes
  and youre out for convicted felons. Next thing
  it will be two strikes, then one strike. Then we
  will be sticking people in jail for life for
  misdemeanors. Its not good policy.

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Slippery Slope

• ExampleGays in the military? If we allow that,
  then next time well be letting women into the
  mens barracks. And the next thing you know,
  women, men, gays, everyone--theyll all be
  showering together and sleeping in the same
  bunks. Get real.

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Misplacing the Burden of Proof

• Misplacing the burden of proof occurs when the
  burden of proof is placed on the wrong side of an
  issue.

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Misplacing the Burden of Proof

• 1. The less initial plausibility a claim has, the
  greater the burden of proof we place on someone
  who asserts that claim.

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Misplacing the Burden of Proof

• 2. Other things being equal, the burden of proof
  falls automatically on those supporting the
  affirmative side of an issue rather than on those
  supporting the negative side.

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Misplacing the Burden of Proof

• When someone claims that we should believe in
  such-and-such because nobody has proved it isnt
  so, we have a subtype known as appeal to
  ignorance.

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Misplacing the Burden of Proof

• 3. Special circumstances like court or contracts
  will specify where the burden of proof lies so
  there are no doubts or confusion about who needs
  to prove what.

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Misplacing the Burden of Proof

• Example I beg to differ, Officer, but sometimes
  you people go overboard talking about the dangers
  of fast driving. If you can prove that theres
  actually a child near the street right now, and
  that the child would have stepped out in front of
  my car, then Ill grant you that going fifty-five
  was dangerous.

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Misplacing the Burden of Proof

• Example Preferential treatment in hiring is
  something we must support after all, can you
  think of a reason why we shouldnt?

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Begging the Question

• We are guilty of begging the question when we ask
  our audience to accept premises that are as
  controversial as the conclusion were arguing for
  and are controversial on the same grounds.

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Begging the Question

• Example The ACLU? Yeah, I know about them, and I
  dont like them very much. Theyre the ones who
  furnish free lawyers for criminals.

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Begging the Question

• Example No, I don NOT believe that a murderer
  ought to be allowed to live. No way! Murderers
  have forfeited the right to live because anyone
  who murders another person has lost that right.