Logical Conflict

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Logical Conflict

• The Logic of Disagreement

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Relationships of Claims
NOT IN LOGICAL CONFLICT Claims are not in
logical conflict if they COULD be true at the
same time. Note that it is not necessary that
they actually be true at the same time.
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Relationships of Claims
NOT IN LOGICAL CONFLICT Claims are not in
logical conflict if they COULD be true at the
same time. Note that it is not necessary that
they actually be true at the same time. IN
LOGICAL CONFLICT Claims are in logical conflict
if they COULD NOT be true at the same time. If
claims are in logical conflict, it is necessary
that at least one of them be false.
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Logical Conflict Flow Chart
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Common Mistakes in CW

• Many of the examples given in the in-class
  writing included the following mistakes.
• Many claims expressed as contraries were not in
  logical conflict (both of the given claims could
  both be true at the same time).

1. Amy is a good tapdancer. 2. Amy has a broken
ankle.
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More examples...

• Melrose Ave. is in Hollywood.
• Sunset Blvd. is in Hollywood.
• It snows in Sacramento, CA.
• It snows in New Mexico.
• 5. I am a chemistry major at Chico State.
• 6. I am a biology major at Chico State.

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Another common mistake

• Many of the examples given for contradictories
  were actually contraries.
• A few examples
• 1. It's 80 degrees in LA right now.
• 2. It's below 80 degrees in LA right now.
• 1. During the summer the Pacific Ocean gets
  cooler.
• 2. During the summer the Pacific Ocean gets
• warmer.

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Are these claims in logical conflict?

• Amy finds critical thinking to be an invaluable
  skill which sharpens her mind.
• 2. Amy finds critical thinking lectures to be
  excruciatingly boring.

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How about these?

• Golf is a game which requires extreme mental
  sharpness.
• Golf is a game which requires a fat butt and
  goofy pants.

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.........

• All Chico State students drink ten or more drinks
  per week.
• John is a Chico State student who consumes two
  drinks a week.

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Finally....

• Everyone believes the moon is made of green
  cheese.
• Someone does not believe that the moon is made of
  green cheese.

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Let us try again!

• Pertaining to any topic you find suitable, give
  an example of each type of logical relation a
  pair of claims can have.
• In other words, give an example of each of the
  following and label them
• claims that are not in logical conflict
• claims that are contradictory
• claims that are contrary