1. Introduction to Logos
Logos as Reasoning

2. Fact and Opinion What is a “fact” and how can you tell?
What are some “facts” you know? Where do you find them?
What is an opinion? How can you tell that from a fact?
Is it possible to have contradictory facts?
How are facts found out/discovered/known?
How do you form an opinion about something?

3. Logos: Definition
Logos is the art of using facts and reasoning for effective argumentation
Reasoning: Inductive and Deductive
Logical Fallacies / Where reasoning breaks down
Reasoning: Syllogisms

4. Deduction
Deduction: Process of starting with universals / assumptions and leading to specifics
General -> specific
Example: 1) All people are mortal; 2) Chuck Norris is a person; 3) Therefore Chuck Norris is mortal

5. Induction
Induction: Process of leading from particulars to universals / general conclusions
Specific examples -> General conclusion
Example:
If Chuck Norris is good at kicking, and Chuck Norris is good at punching, Chuck Norris must be good at all martial arts.

6. Syllogisms and Enthymemes?
Logos isn’t just about using facts or statistics in argument, but rather its about being able to use those facts through reasoning.
Syllogisms & enthymemes are two ways to reason in an argument.

7. What is a syllogism?
A type of deductive reasoning (general to specific)
Consists of a major premise, a minor premise, and a conclusion
Almost any argument can be broken down into a syllogism.

8. Premises Major premise: A general statement.
Minor premise: A specific statement.

Conclusion: based on the two premises.

9. Example I Healthcare is too costly in America
Most middle-class families and employers cannot afford heathcare costs.
Therefore, we need healthcare reform in America

10. Example II
All people regardless of race were created equal and have rights.
Segregation in schools and busses treats people unequally.
Therefore, we need a constitutional amendment to guarantee equality for all.

11. Example III
"The gloves didn't fit. If it doesn't fit, you must acquit."-- Johnny Cochran, Closing arguments of the O.J. Simpson trial
The glove was used in the murder and therefore owned and worn by the murderer. (major premise)
The gloves didn't fit. (minor premise)
You must acquit. (conclusion)

12. Examples V
Tomatoes taste salty. Tomatoes are red. All red foods taste salty.
Bobby stole a bicycle. Bobby is poor. All poor people are thieves.
Snails crawl on the ground. I can crawl on the ground Therefore, I’m a snail.

13. The point?
While they can be a powerful tool, syllogisms can also lead to overgeneralizations and faulty reasoning.
In groups: write two syllogisms based on arguments in current American politics

14. Enthymemes
Enthymemes are like syllogisms except that they are missing the minor premise.
These are used more frequently than syllogisms in written and spoken arguments.

15. Examples of Enthymemes
“Women should be allowed to join combat units because the image of women in combat would help eliminate gender stereotypes.”
Claim: Women should be allowed to join combat units.
Stated Reason: Because the image of women in combat would help eliminate gender stereotypes.
Unstated Assumption: Gender stereotypes are harmful and should be eliminated (or girls with guns = cool?)

16. Examples
Buy this car stereo system because it has a 200-watt amplifier.
Claim: Buy this car stereo system
Reason: Because it has a powerful amplifier
Unstated assumption: loud music rocks / loud car stereo systems are cool

17. Example The ladies like “Axe” body spray (“Axe” smells great.)
If you use “Axe”, you’ll attract women

18. But what about bad reasoning?
Logical or verbal fallacies - incorrect, bad, faulty reasoning
Can lead readers astray
Can be incredibly convincing!

19. Fallacies Activity - Skits
Using the list of Logical Fallacies, develop a short skit of your assigned fallacy.
Be prepared to present your skit to the class.
Groups who guess correctly can earn up to 5 bonus points.

20. Arguments in Action
In groups, analyze, “Third Party Rising” in the New York Times (Op Ed):
Answer the following questions (in groups)
What is the overall argument?
What is the supporting evidence?
What appeals are being made from ethos?
What reasoning is being used? Inductive or Deductive?
Identify at least two syllogisms or enthymemes
Are there any fallacies? If so, what are they?