Logical Fallacies

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Logical Fallacies

• English 102

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What is a logical fallacy?

• A fallacy is an error of reasoning. These are
  flawed statements that often sound true
  
• Logical fallacies are often used to strengthen an
  argument, but if the reader detects them the
  argument can backfire, and damage the writers
  credibility

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Why study logical fallacies?

• It is important to develop logical fallacy
  detection skills in your own writing, as well as
  others.
  
• Think of this as intellectual kung-fu the art
  of intellectual self defense.

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Types of Logical Fallacies

• Fallacies of Relevance
• These fallacies appeal to evidence or examples
  that are irrelevant to the argument at hand.
  
• Bandwagon Approach
• It must be cool because everyone is doing it

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Slippery Slope

• If A happens, then eventually through a series of
  small steps, through B, C,..., X, Y, Z will
  happen, too, basically equating A and Z.
  
• Example?

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Ad hominem

• This is an attack on the character of a person
  rather than their opinions or arguments.
  
• Example?

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Genetic Fallacy

• A conclusion is based on an argument that the
  origins of a person, idea, institute, or theory
  determine its character, nature, or worth.
  
• Example?

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False Dilemma

• The arguer claims that there are only two options
  and one is unacceptable so we must accept the
  other.  However in actuality there are other
  alternatives.

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Hasty Generalization

• Any argument that draws a generalization based on
  a small or unrepresentative sample size.
  
• Example?

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Red Herring

• When the arguer changes the subject and take the
  listener down a different, unrelated path.

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Appeals to force/fear

• The arguer tries to get you to accept their view
  on the grounds that you will be harmed if you
  dont.

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Appeals to pity

• The arguer tries to get you to accept their view
  on the grounds that they will be harmed if you
  dont.

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Prejudicial language

• Example?

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Guilt by Association

• The arguer suggests her opponents views should
  be rejected because the opponent is a member of a
  perceived disreputable group or the views of the
  opponent are also held by persons of a
  disreputable group.

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Resources 

• The Owl at Purdue
• THE Nizkor Project