FALLACY arguments, like men, are often pretenders. Plato

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FALLACYarguments, like men, are often
pretenders. Plato
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Under what discipline would you study fallacies?

• Logic

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Remember, in forming an argument you may appeal
to . . .

• Ethos, appeal to ethics or morality
• Pathos, appeal to pity or the emotions
• Logos, appeal to reason

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But, what exactly is logic?

• Logic is the study of the methods and principles
  used to distinguish good from bad reasoning the
  purpose of logic to test the correctness of
  arguments.

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• Mr. Scrooge, I certainly deserve a raise in pay.
  I can hardly manage to feed my children on what
  you have been paying me. And my youngest child,
  Tim, needs an operation if he is ever to walk
  without crutches.

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Fallacy

• An unsound argument in which a mistake is made
  when moving from a premise to a conclusion.

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Yet this definition assumes that we know what
premise, conclusion and argument mean?
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Premise

• A statement supporting a conclusion.
• Example Since no gun powder residue was
  detected on the terrorists clothing or body,
  . . .
• (Words which indicate a
• premise since, because,
• as, for )

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Conclusion

• A statement concluded from the premise of an
  argument.
• Example . . . , the FBI concluded he could
  not have been the murdered.
• (Words which indicate a conclusion therefore,
• hence, thus, so)

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An argument is formed when a conclusion is
drawn from a premise.

• Example Since no gun powder residue was
  detected on his clothing or his body, the FBI
  concluded he could not have been the murderer.

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So, the logical mind will ask?

• Does the conclusion reached follow from the
  premise used or assumed?

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Now lets take another look at the definition of
a fallacy

• A fallacy is an unsound argument in which the
  conclusion does not follow from the premise.

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Appeal to Pity, Argumentum ad Misericordiam

• A fallacy committed when pity is appealed to for
  the sake of getting a conclusion accepted.
• Example But Mr. Gonzalez, I have failed 2326
  four times in a row. Dont you think I deserve
  to pass it this time around? How many times do I
  have to fail it before I pass it?
• Officer, I know I was speeding, but I just paid
  for a speeding ticket just last month. Can you
  give me a break?

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Attacking the person, Argumentum ad Hominem

• It is committed when instead of trying to
  disprove the truth of what is asserted, one
  attacks the person who made the assertion. This
  argument is fallacious because the personal
  character of a person is logically irrelevant to
  the truth or falsehood of what that person says
  or the correctness or incorrectness of that
  persons argument.

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Example

• How can you say that he is a good writer when he
  failed English throughout his high school years?
• There is no way I could follow that particular
  religious leader since I know for a fact that in
  his twenties he was one of the most sinful people
  I ever knew.

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Argument from ignorance or Argumentum ad
ignorantiam

• This occurs when it is argued that a proposition
  is true simply on the basis that it has not been
  proven false, or that it is false because it has
  not been proven true.
• Example There must be ghosts because no one has
  ever been able to prove that there arent any.
• Since you cannot prove that there is water on
  Mars, then there must be water on Mars.

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Appeal to popularity or Argumentum ad Populum

• The attempt to win popular assent to a conclusion
  by arousing the emotions and enthusiasms of the
  multitude, rather than by appeal to relevant
  facts. This fallacy is also known as jumping on
  the bandwagon.
• Example Since so many people are now using
  tattoos, it follows that everyone should get one
  before Christmas.

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Prejudicial language

• Charged, loaded or emotive terms are used to
  attach value or moral goodness to believing in a
  particular proposition.
• Example
• Any good Catholic would agree that abortion is
  tantamount to murder.
• Any reasonable IRS agent will agree that our
  income tax is way too high.

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Slippery slope

• On the basis of a sequence of several
  unacceptable premises, an illegitimate
  conclusion is drawn.
• Example You should never gamble. Once you
  start gambling you will find it hard to stop.
  Soon you are spending all your money on gambling,
  and eventually you will turn to a life of crime.

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False dilemma

• A limited number of options (usually two) is
  given while in reality there are more options.
  Putting issues or opinions into black and white
  terms is a common instance of this fallacy.
• Example
• AmericaLove it or leave it.
• Every person is either wholly good or wholly
  evil.

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Complex question

• It is obvious that there is something funny
  about questions like Have you given up your evil
  ways? or Have you stopped cheating at cards?
  These are not simple questions to which a
  straight forward yes or no answer can be
  given. Such questions presuppose that a definite
  answer has already been given to a prior question
  that was not even asked.
• Example Have you stopped beating your husband?

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Begging the question or Petitio Principii

• If one assumes as a premise for an argument the
  very conclusion it is intended to prove, the
  fallacy committed is that of begging the question
  This occurs when the same proposition is
  repeated in both the premise and the conclusion.
  This is what is commonly referred to as circular
  reasoning.
• Example
• He is an unjust man. Thus, it may me asserted
  that he is an an unfair man.

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Appeal to authority or Argumentum ad verecundiam

• An authority is appealed to for testimony in
  matters outside the province of that authoritys
  special field. For example, an appeal to the
  opinion of a great physicist like Einstein to
  settle a political or economic argument would be
  fallacious. He may be an authority in science,
  but not government.
• Example
• President Bush has stated that walking is the
  best exercise for your heart.

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Anonymous authority

• The fallacy of anonymous authority is similar to
  the fallacy of appeal to authority, but in this
  particular fallacy the authority appealed to is
  not specified. The authority is anonymous or
  unknown and thus unreliable.
• Example
• Government experts have reported that anthrax
  has been found in 95 of federal government
  buildings.