LOGIC

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LOGIC The principles of reasoning particularly
those that examine arguments in support of a
conclusion or opinion
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FACT

• Verifiable evidence can be proven true or false
  

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OPINION

• Personal view or prediction cannot be verified,
  may be well supported by reason may not

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Valid

• Reasoning makes sense provide evidence, doesnt
  have to be a fact

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Invalid

• Reasoning is faulty makes no sense, lack of
  evidence

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Inductive Reasoning

• Presents its evidence, then provides a conclusion
• Think of it as a detective they gather the
  evidence and then make a conclusion

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Inductive Reasoning

• You wake up to what looks like a full moon
  shinning through your window
• Your mom put a snow shovel next to the door
• The radio says school is canceled
• Conclusion
• There was a big snow storm

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Inference

• Using evidence and inductive reasoning to make an
  educated guess

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Deductive Reasoning

• Follows a formal approach to drawing conclusions,
  moving through the steps of the syllogism

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Syllogism

• Three step process
• 1-Generalization or major premise
• 2-Specific case or minor premise
• 3-Conclusion

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Major Premise
Minor Premise
Conclusion
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Validity

• Pay attention to the major premise!
• Some goats eat paper
• Larry is a goat
• Therefore, Larry eats paper
• INVALID

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Example

• All men are mortal
• Socrates is a man
• Therefore, Socrates is mortal

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• Some goats eat paper
• Larry is a goat
• Therefore, Larry might eat paper
• All goats eat paper
• Larry is a goat
• Therefore, Larry eats paper

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How about this one?

• Also Pay attention to what you know
• All cats have tails
• Lanny has a tail
• Therefore, Lanny is a cat
• INVALID - A lot of animals have tails

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• All rats like cheese
• Robert likes cheese
• Therefore, Robert is a rat
• INVALID - I like cheese and I like to think
  Im not a rat!

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The Art of Persuasion
Ethos
Logos
Pathos
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Ethos

• An appeal based on the character of the speaker
• An ethos driven document or speech relies on the
  reputation of the author

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To Develop Ethos

• Language appropriate to audience and subject
• Restrained, sincere, fair minded presentation
• Appropriate level of vocabulary
• Correct grammar

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• Acme Gizmotronics, the company that you've
  trusted for over 100 years, has recently entered
  the World Wide Web! Now you can purchase our fine
  products through the internet. Our quality
  gizmos, widgets, and thingamabobs can be shipped
  to you within minutes. All come with the famous
  lifetime guarantee that makes Acme the company
  that the world depends on for it's gizmo needs.

Our spokesperson, Mr. Coyote says "I'm not really
a coyote, but I play one on tv. I've used Acme
products for years. Their slingshots, rocket
launchers, crowbars, pogo sticks, and power pills
are the best around. And don't forget their
high-powered dynamite! I buy everything from
Acme. They are the company that I trust the
most."
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• The ACME homepage is an example of ethos because
  of the way it keeps referring back to the
  character of ACME
• ACME is a company that "you have trusted for over
  100 years." They even have a spokesperson
  vouching for their integrity

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Logos

• Logos is appeal based on logic or reason
• Documents distributed by companies or
  corporations are logos-driven
• Scholarly documents are also often logos-driven

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To Appeal to Logic (Logos)

• Theoretical, abstract language
• Denotative (straight forward) meanings/reasons
• Literal and historical analogies
• Definitions
• Factual data and statistics
• Quotations
• Citations from experts and authorities
• Informed opinions

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• ACME's New Dihydro-Cesium Detonation Process
• By combining cesium and dihydro-oxide in
  laboratory conditions, and capturing the released
  energy, ACME has promised to lead the way into
  the future. Our energy source is clean, safe, and
  powerful. No pollutants are released into the
  atmosphere. The world will soon have an excellent
  source of clean energy.Once the entire world is
  powered by ACME's generators, we can all relax
  and enjoy a much easier life.

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• The ACME Research page is primarily logos-based
  because it appeals to the reason of people
  reading it
• It suggests that Cesium will provide the world's
  energy for a very long time - it is clean, safe,
  and efficient, all of which are appeals to the
  logic of the audience
• By using such convincing reasons in it's
  argument, ACME hopes to provide the world's
  energy

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Pathos

• Pathos is appeal based on emotion
• Advertisements tend to be pathos-driven

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To Appeal to Emotion (pathos)

• Vivid, concrete language
• Emotionally loaded language
• Connotative (suggest or imply) meanings
• Emotional examples
• Vivid descriptions
• Narratives of emotional events
• Emotional tone
• Figurative language (simile, analogy, etc.)

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• Acme Gizmotronics is trying to squeeze energy out
  of destructive explosions. And, they are dumping
  waste cesium onto the shores of our island,
  threatening the environment. Studies have shown
  that the dihydro-cesium reactor will destroy the
  island's ecosphere in less than four months!
• What can you do about this?
• Don't let them get away with it! Boycott Acme
  products! And call your representatives, and tell
  them you support stricter legislation to prevent
  things like this!

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• Pathos is an argument based on emotion, playing
  on sympathy, fears, and desires
• The Say "NO!" To Acme! page is pathos-based
  because it relies on an emotional response from
  the people reading it
• It attempts to sway people to its side, against
  the "commericial hordes" of Acme