FOCUS%20ON%20LOGOS

1
FOCUS ON LOGOS

• Formulating a logical argument using Inductive
  and Deductive Reasoning

2
Rhetorical Triangle
3
Appeals to Logic (logos)

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

4

• ARGUMENT CLAIM SUPPORT FOR CLAIM
• Arguments use either DEDUCTIVE or INDUCTIVE
  reasoning.

5
Deductive Arguments

• argument from the general to the particular.
• leads to certain conclusions.
• arguments are valid or invalid.

6
Examples of Deductive Reasoning

• All men are mortal (major premise)
• Socrates was a man (minor premise)
• Therefore Socrates was mortal. (conclusion)
• If it rains, the sidewalks become wet
• It is raining
• Therefore the sidewalks are wet.

7
Deductive reasoning contd.

• All women are brilliant. (major premise)
• I am a woman. (minor premise)
• Therefore, I am brilliant. (conclusion)
• Everyone who has been exposed to the Ebola virus
  has died.
• John Q. has been exposed to the Ebola virus.
• John Q. will die.

8
Inductive Arguments

• argument from particular observations to general
  conclusions.
• leads to probable conclusions, not necessary
  ones.
• arguments can be better or worse depending on
  degree of probability.

9
Examples of Inductive Reasoning

• Socrates was Greek
• Most Greeks eat fish
• Socrates ate fish.
• Eddie has failed to follow through with his
  education, in his relationships with women, and
  with the jobs that he has previously held,
  therefore he will probably not follow through on
  this assignment.

10
Inductive Arguments contd.

• Many people who smoke seem to get cancer. 
• Thus, if you want to avoid getting cancer,
  don't smoke.

11
Logical Fallacies (p. 631 in RCWW)

• Example
• Why is counterfeiting illegal? Ill tell you why.
  It is because it is against the law!
• We sin, because we are sinners.

12
LOGICAL REASONING EXERCISE

1. Penguins make great pets.
2. Milk should be banned.
3. People really dont need skin.
4. The new pizza diet is wonderful.
5. Tabloids should replace texts.
6. Humans should always go barefoot.
7. Hot-air balloons make great commute vehicles.
8. Children should be able to vote.