Are There Any Fallacies in the Reasoning?

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Are There Any Fallacies in the Reasoning?

• CO SCI 58 Asking the Right Questions

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Fallacies

• Youve learned to identify issue and conclusion,
  reasons, ambiguities and assumptions. Now youre
  ready to start evaluating the quality of the
  reasoning.
• A fallacy is a reasoning trick that an author
  uses while trying to persuade you to accept a
  conclusion.

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Common Fallacies

• Many fallacies are so common they have been given
  formal names.
• Its not important to memorize the names, just to
  be able to identify that there is a fallacy.

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Ad Hominem

• Proving a point by attacking a person or group
  rather than ideas. Name-calling is a common
  practice.
• Sue The sooner we get out of Afghanistan, the
  better. At some point we need to say enough!
  Our continued concentration on Afghanistan is
  hampering our overall effort against terrorism.
• Rick Why is it that you gutless liberals want to
  see us surrender to terrorists? We need to fight
  until we have won the war.

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Ad Hominem

• Sue The sooner we get out of Afghanistan, the
  better. At some point we need to say enough!
  Our continued concentration on Afghanistan is
  hampering our overall effort against terrorism.
• Rick Why is it that you gutless liberals want to
  see us surrender to terrorists? We need to fight
  until we have won the war.
• This also demonstrates another type of fallacy
  called straw man.

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Appeal to Emotion

• Authors use words that have an emotional appeal
  to sway you. Appeal to pity is the most common
  one for Ms. Lanes class.
• Please give me more time for my assignment. My
  beloved best friend is so sick and I am worried
  to death. I just cant concentrate on school
  right now.

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There are Lots of Appeal Fallacies!

• Appeal to Authority
• Appeal to Belief
• Appeal to Tradition
• Appeal to Fear
• Appeal to Flattery
• Appeal to Ridicule
• Appeal to Spite We could go on.

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Appeal to Questionable Authorityor Tradition

• Weve always done it this way. Or X is
  against/for it so you should be too. Is X a
  reliable
• Our workers have always been happy working 9-5
  theres no need to change that schedule.
• Wondering about your future? Ask Zena, Beverly
  Hills own phychic/clairvoyant. Zena has been
  sought after and quoted in entertainment
  magazines, from TVs Good Morning America, to
  Time. Including the Palm Beach Daily News and the
  Palm Beach Post. (Ad from Random Lengths)

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Ad Populum(also called an Appeal to Popularity)

• Appeals to group-approved attitudes.
• Most Americans agree that
• Everybody knows that.
• Americans want to be protected against
  terrorists. We must use face recognition systems
  in public gathering places.
• Thats not fair. All the other kids get to go to
  the rave!
• Everyone knows the governor is unreliable if we
  keep trusting him not to raise taxes, we could
  all be in debt by next year.

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Equivocation

• A key word or phrase is used with two or more
  meanings in an argument such that the argument
  fails to make sense once the shifts in meaning
  are recognized.
• When Bill Clinton claimed I never had sex with
  that woman, he was equivocating the half-truth
  was that by a certain very limited definition of
  having sex, he could say thatbut he did not
  reveal, until pressed, what definition of having
  sex he was going by.

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Slippery Slope

• Making the assumption that a proposed step will
  set off a chain of undesirable events, when
  procedures exist to prevent that sequence of
  events.
• Marijuana should not be legalized for any reason
  medical or otherwise. Legalization would imply
  that there are no dangers to drug use. Our
  children will get the message that it is okay to
  experiment with heroin and designer drugs.

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Extension Fallacy

• Attacking a position that appears similar to but
  is actually different from an opponents
  position. Then concluding that the opponents
  real position has been refuted.
• I support the idea of ones choice to have their
  belly button pierced. Everybody should have the
  freedom to express their uniqueness in a way that
  they really enjoy and makes them feel good about
  themselves. What is more of a unique way than
  self-expressing yourself through body
  decorations?
• Adapted from Ravy Sams letter to the Press
  Telegram. 10-6-02 page A21

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Also called straw man

• The straw man here is the idea of freedom of
  expression to refute parental arguments against
  belly button piercing.
• Parents are usually concerned with health issues
  like infections and tearing. Theyre not against
  self-expression.

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Straw Man

• Sue The sooner we get out of Afghanistan, the
  better. At some point we need to say enough!
  Our continued concentration on Afghanistan is
  hampering our overall effort against terrorism.
• Rick Why is it that you gutless liberals want to
  see us surrender to terrorists? We need to fight
  until we have won the war.
• Sue says that the overall effort against
  terrorism is harmed by the focus on Afghanistan.
  Does Rick answer this?

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Either 0r FallacyAlso called a False Dilemma

• The writer oversimplifies an issue by stating
  only two choices when there are really more.
  Watch for
• either .or
• the only alternative is..
• the two choices are
• because A has not worked, only B will

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Example False Dilemma

• The Chinese government is so fierce about
  controlling the information dispensed among its
  citizenry that it recently shut down thousands of
  Internet cafes and blocked search engines Google
  and AltaVista.
• Chinese citizens deserve to become full members
  of the Internet society. American companies must
  show support for our values and refuse to provide
  Internet services in China until these gag orders
  are lifted.

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Companies must?

• American companies must refuse to provide
  Internet services in China
• Its presented as though there are two black and
  white options, no Internet service for the
  Chinese people or wide open freedom.

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Red Herrings

• This fallacy diverts your attention away from the
  real issue. The red herring is the other issue
  hes using to misdirect you.
• Kids are experts
• Why didnt you call me when you didnt come home
  by 11p.m. from your date?
• My brother doesnt have a curfew for dates.

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Wishful ThinkingConfusing What Should Be and
What Is
Reality or what is, is often in conflict with
what should be. Computer game makers should
not be forced to participate in a rating system.
Parents should review the game content to see if
they deem it appropriate for their child.
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Confusing Naming with Explaining
Naming makes us think that we have identified
something that the person has or is that makes
him act accordingly. A different name for a
behavior is presented as the cause of it. Sony,
Panasonic and other electronics manufacturers are
against legislation requiring recycling fees.
Its big business versus the earth. Big
business is greedy and bad, earth is good
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Perfect Solutions

• If a solution doesnt completely eliminate the
  problem, that doesnt make it bad. It may be
  superior to no solution at all.
• We should not go through the extra expense of
  installing a firewall because hackers will still
  find security holes.

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Begging the Question

• The speaker may put the burden on you to prove
  that his conclusion is not correct instead of
  giving reasons.
• Isnt is worth 10 a month to protect your home
  computer from hackers?
• Show me that space aliens dont exist!
• Or he may build on an unproven assumption.
• Have you stopped beating your wife?

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More Begging the Question

• Sometimes the reason is just the conclusion
  restated in a slightly different way. Its
  circular reasoning.
• Internet filtering software should be installed
  in schools because undesirable sites will be
  blocked.

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What Kind of Fallacy is it?

1. We need to get the latest iPad right away.
   Everyone at school has one.
2. Dont re-elect President Obama. He is a Marxist
   and a racist.
3. Gays should not be allowed to marry. Marriage has
   always been between a man and a woman.
4. Dont swim in the ocean. TV star Nicole "Snooki"
   Polizzi says "the water's all whale sperm.
5. You can stop eating animal products and be
   healthy or keep eating them and be unhealthy.
6. Why should I do my math homework? I dont want to
   be a math teacher.

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Answers

• Ad populum
• Ad hominem
• Appeal to tradition
• Questionable authority
• False dilemma
• Red Herring.
• End of Lecture