1. Aristotelian Logic & Fashioning an Argument
A Study of Deductive Reasoning

2. What is Argumentation?
Argumentation is a process of reasoning that asserts the soundness of a debatable position, belief, or conclusion.
Can be used to:
Convince other people to accept or acknowledge the validity of your position
Defend your position from other points of view
Question or refute a position you believe to be misguided, untrue, dangerous, evil, or absurd.

3. Persuasion vs. Argumentation
Persuasion is a more general term that refers to how a writer influences an audience to adopt a belief or follow a course of action. Pathos, Logos, Ethos…
Argumentation is the appeal to reason…It is more concerned with demonstrating that certain ideas are valid and others are not.

4. Planning your Essay
Topic: ideally, you should have an intellectual and emotional stake in your topic!
You should keep an open-mind in the research phase. You must be willing to see all sides of the issue.
Purpose: What you expect your argument to accomplish and how you wish your audience to respond.
Thesis: Must take a stand….Must be debatable…AKA Must have a reasonable ANTITHESIS

5. EVIDENCE Facts… Opinions… which are Interpretations of facts
NOT ALL OPINIONS ARE CREATED EQUAL!
Criteria for evidence
Relevant…make sure it’s pertinent to your argument!
Representative and typical…Basically, you should avoid cherry-picking evidence and opinions to make your argument look stronger than it is.
Sufficient…it needs to be enough!

6. Refutation
When planning your essay, you should write down all the arguments against your thesis.
Your essay must deal with your opposition’s argument…It must either..
Show they are unsound, unfair, or weak.
If it’s super strong, concede it’s strength…perhaps point out some weaknesses…then move back to showing why your point of view is strong.

7. Why learn this stuff? Logic = Reasoning Basis of academic thought
Creation of argument

8. How do I demonstrate logic?
Make obvious, explicit connections between your major thoughts and ideas
You want someone to FOLLOW your train of thought.

9. Aristotle Worked with syllogisms Formal system of thought
Provides a method for connecting ideas together

10. Syllogism Ex: 1) Wood floats in water. 2) Ships are made of wood
3) Therefore ships float in water.

11. Syllogisms
#1 and #2 are both a premise.
#3 is a conclusion

12. Syllogism Example Reiterated
Premise #1: Wood floats in water.
Premise #2: Ships are made of wood.
Conclusion: Therefore, ships float in water.

13. If all humans are mortal, and all Greeks are humans,
Syllogism Practice
If all humans are mortal,
and all Greeks are humans,
then all Greeks are mortal.

14. This type of logic isn’t perfect!
All chickens have two legs.
Aristotle has two legs.
Therefore, Aristotle is a chicken.
=flawed
However, this isn’t the point!

15. So?
When you write an essay, watch your premises. They should lead to a valid conclusion.

16. Examples – Fill in the missing component
All trees have root systems.
Therefore, All trees need nitrogen.
All root systems need nitrogen.

17. Examples – Fill in the missing component
All fruits grow on trees
Therefore, all oranges grow on trees
All oranges are fruits

18. Examples – Fill in the missing component
All bachelor's are single
Johnny is single,
Hence, Johnny is a bachelor

19. Ex: Logic w/o syllogism format
Everyday I go to work. This journey from my home to my office takes one hour. My office starts at eight o' clock in the morning. So, if I leave my home at seven o' clock in the morning, I will reach the office in time.

20. Validity and Soundness
Argument
Validity and Soundness

21. Argument: Validity
A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid.

22. Argument: Validity
Valid arguments do not require true premises.

23. Ex: Valid Argument – True premises
Either Elizabeth owns a Honda or she owns a Saturn.
Elizabeth does not own a Honda.
Therefore, Elizabeth owns a Saturn.

24. Ex: Valid Argument – False premises
All toasters are items made of gold.
All items made of gold are time-travel devices.
Therefore, all toasters are time-travel devices.

25. Argument - Soundness
A sound argument is one that is not only valid, but begins with premises that are actually true

26. Soundness A deductive argument is sound if and only if
1) it is both valid, and
2) all of its premises are actually true.
Otherwise, a deductive argument is unsound.

27. QUANTIFIERS Ex: Sound argument No felons are eligible voters.
Some professional athletes are felons.
Therefore, some professional athletes are not eligible voters.
QUANTIFIERS

28. Practice…