Logical-Fallacies-and Appeals

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Logical-Fallacies-and Appeals
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LOGIC VOCAB

• Premise Proposition used as evidence in an
  argument.
• Conclusion Logical result of the relationship
  between the premises. Conclusions serve as the
  thesis of the argument.
• Argument The assertion of a conclusion based on
  logical premises.
• Syllogism The simplest sequence of logical
  premises and conclusions, devised by Aristotle.
• Enthymeme A shortened syllogism which omits the
  first premise, allowing the audience to fill it
  in. For example, "Socrates is mortal because he
  is a human" is an enthymeme which leaves out the
  premise "All humans are mortal."
• Induction A process through which the premises
  provide some basis for the conclusion.
• Deduction A process through which the premises
  provide conclusive proof for the conclusion.

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DOES LOGIC ALWAYS WORK?

• Logic is a very effective tool for persuading an
  audience about the accuracy of an argument.
  However, people are not always persuaded by
  logic. Sometimes audiences are not persuaded
  because they have used values or emotions instead
  of logic to reach conclusions. But just as often,
  audiences have reached a different logical
  conclusion by using different premises.
  Therefore, arguments must often spend as much
  time convincing audiences of the legitimacy of
  the premises as the legitimacy of the
  conclusions.

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So how do I find fallacies in my own writing?

• Here are some general tips for finding fallacies
  in your own arguments
• Pretend you disagree with the conclusion youre
  defending. What parts of the argument would now
  seem fishy to you? What parts would seem easiest
  to attack? Give special attention to
  strengthening those parts.
• List your main points under each one, list the
  evidence you have for it. Seeing your claims and
  evidence laid out this way may make you realize
  that you have no good evidence for a particular
  claim, or it may help you look more critically at
  the evidence youre using.

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So how do I find fallacies in my own writing?

• Learn which types of fallacies youre especially
  prone to, and be careful to check for them in
  your work. Some writers make lots of appeals to
  authority others are more likely to rely on weak
  analogies or set up straw men. Read over some of
  your old papers to see if theres a particular
  kind of fallacy you need to watch out for.
• Be aware that broad claims need more proof than
  narrow ones. Claims that use sweeping words like
  all, no, none, every, always, never,
  no one, and everyone are sometimes
  appropriatebut they require a lot more proof
  than less-sweeping claims that use words like
  some, many, few, sometimes, usually,
  and so forth.
• Double check your characterizations of others,
  especially your opponents, to be sure they are
  accurate and fair.

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Rhetorical Appeals

• Ethos, Pathos, and most importantly Logos
• Ethos - ethics or ethical. Better known as
  image
• Pathos - the emotion of the audience
• Logos logic of the argument.
• Persuasion, to a large extent, involves
  convincing people to accept our assumptions as
  probably true. Similarly, exposing questionable
  assumptions in someone else's argument is an
  effective means for preparing the audience to
  accept your own contrary position

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LETS PLAY A

• GAME

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a. slippery slopeb. black-or-whitec.
bandwagond. false cause

• Example Pointing to a fancy chart, Roger shows
  how temperatures have been rising over the past
  few centuries, whilst at the same time the
  numbers of pirates have been decreasing thus
  pirates cool the world and global warming is a
  hoax.

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a. ambiguityb. appeal to pityc. burden of
proofd. slippery slope

• Example The fallacy of urging an audience to
  root for the underdog regardless of the issues
  at hand. Those poor, cute little squeaky mice
  are being gobbled up by mean, nasty cats that are
  ten times their size!

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a. black-or-whiteb. ad hominemc. slippery
sloped. burden of proof

• Example Colin Closet asserts that if we allow
  same-sex couples to marry, then the next thing we
  know we'll be allowing people to marry their
  parents, their cars and even monkeys.

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a. bandwagonb. ad hominemc. burden of proofd.
composition/division

• Example After Sally presents an eloquent and
  compelling case for a more equitable taxation
  system, Sam asks the audience whether we should
  believe anything from a woman who isn't married,
  was once arrested, and smells a bit weird.

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a. black-or-whiteb. composition/divisionc.
ambiguityd. burden of proof

• Example Bertrand declares that a teapot is, at
  this very moment, in orbit around the Sun between
  the Earth and Mars, and that because no one can
  prove him wrong, his claim is therefore a valid
  one.

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a. ambiguityb. black-or-whitec. begging the
question(circular reasoning)d. bandwagon

• Example The witchcraft problem is the most
  urgent challenge in the world today. Why? Because
  witches threaten our very souls

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a. non sequiturb. bandwagonc.
composition/divisiond. ambiguity

• Example The fallacy of offering reasons or
  conclusions that have no logical connection to
  the argument at hand (e.g. The reason I flunked
  your course is because the government is now
  putting out purple five-dollar bills!)

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a. red herringb. composition/divisionc.
black-or-whited. false cause

• Example An irrelevant distraction, attempting to
  mislead an audience by bringing up an unrelated,
  but usually emotionally loaded issue. E.g., "In
  regard to my recent indictment for corruption,
  lets talk about whats really important
  instead--terrorists are out there, and if we
  don't  stop them we're all gonna die!"  

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a. straw manb. bandwagon c. black-or-whited.
slippery slope

• Example Whilst rallying support for his plan to
  fundamentally undermine citizens' rights, the
  Supreme Leader told the people they were either
  on his side, or they were on the side of the
  enemy.

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a. bandwagon b. slippery slope c. false cause
d. ad hominem

• Example  The fallacy of attempting to refute an
  argument by attacking the oppositions personal
  character or reputation, using a corrupted
  negative argument from ethos. "He's so evil that
  you can't believe anything he says."

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• THE END