1. Unit 15: Using Persuasive Strategies (Chapter 17)
“Speech is power; Speech is to persuade, to convert, to compel.”
-- Ralph Waldo Emerson

2. Persuasion
“…is the process of adjusting ideas to people and people to ideas.”
-- Donald C. Bryant, rhetoric scholar
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3. Establishing Credibility
Also known as ethos.
Audience’s perception of the speaker
Various dimensions:
Competence - knowledge & skill
Trustworthiness - believability & honesty
Dynamism - energy level
Charisma - charm, talent & magnetism

4. Credibility
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5. Enhancing Your Credibility
Values and concerns shared with audience
Well-documented evidence
Well-organized ideas
Well-managed delivery

6. Using Logic and Evidence to Persuade
Logos -- formal system of rules to reach a conclusion
Aristotle: “Always prove what you state.”
Reasoning: drawing a conclusion from the evidence.

7. Types of Reasoning
Inductive
Deductive
Causal

8. Inductive Reasoning
Using specific examples or instances to reach a general or probable conclusion.
Used when one can claim that an outcome is probably true because of specific evidence.

9. Testing Inductive Reasoning
Are there enough specific instances to support the conclusion?
Are the specific instances typical?
Are the instances recent?

10. Inductive Reasoning Example
Students are sneezing in dorms and classrooms.
Professors are cancelling classes.
Campus clinic has long waiting lines.
Conclusion: there must be flu on our campus.

11. Deductive Reasoning Opposite of induction.
Conclusion is more certain than probable.
The more value the outcome, the more certain the conclusion.
Start with widely accepted general claim, then move toward specific conclusion illustrating general claim.

12. Structure of Deductive Reasoning
Syllogism -- three part argument
Major Premise: widely accepted general statement.
Minor Premise: specific statement that applies to the major premise.
Conclusion: logical outcome, minor premise exemplifies major premise.
The more value the major premise, the more value the deduction.

13. Testing the Validity of Deductive Reasoning
Is the major premise (general statement) true?
Is the minor premise (specific instance) true?

14. Deductive Reasoning
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15. Deductive Reasoning: An Example
All tough drug laws introduced in medium-sized communities result in diminished drug-related crimes. (generally accepted statement)
San Marcos, Texas is a medium-sized community. (specific case supporting general statement)
Conclusion: San Marcos should institute tough drug laws.

16. Causal Reasoning Relating to events to show connection.
To conclude that one or more events caused another event.
Can move from cause to effect.
Can move from effect to cause.

17. Causal Reasoning
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18. Causal Reasoning Cause to Effect
1. Interest rates have increased this week.
2. The Dow Jones will decrease.
From a known fact to a predicted result.

19. Causal Reasoning Effect to Cause A major earthquake has occurred.
The cause was a shift in a fault line.
From a known result to a predicted cause.

20. Supporting Your Reasoning with Evidence
Use facts
Use value true examples
Use opinions that enhance credibility
Use sound & reliable statistics
Use reluctant testimony -- shows that someone has been convinced
Use new and specific evidence
Use evidence to tell a story

21. Avoid Faulty Reasoning
Be ethical & appropriate with evidence & reasoning.
Fallacy: False reasoning when someone attempts to persuade without adequate evidence, or with arguments that are irrelevant or inappropriate.

22. Faulty Reasoning
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23. Avoid Faulty Reasoning
Causal -- Hurricanes are caused by war
(connection not related)
Bandwagon -- Everyone knows cell phones are safe. (popularity appeals)
Either-Or -- Either you’re with us or you’re against us. (only 2 choices)
Hasty Generalization -- Since my niece is failing, city schools are bad. (quick conclusion)

24. Avoid Faulty Reasoning
Ad Hominem -- What does a divorced man know about parenting? (personal attack)
Red Herring -- Let’s not focus on the lawsuit against me; let’s talk about…”
(changing the topic to distract)
Misplaced Authority -- Jessica Simpson says McMillan trucks are best. (not a true expert)
Non Sequitur -- Support me for Hongress - I have 3 children. (ideas do not follow)

25. Use Emotion to Persuade
Can make people feel pleasure or displeasure
Can make people feel energized
Can make people feel dominance

26. Organizing Persuasive Messages
State your strongest arguments first
Do not bury key arguments in the middle
Save action calls for the end
Consider presenting both sides of an issue
State and refuse counterarguments

27. Strategies for Organizing Persuasive Messages
Problem -- Solution
Refutation
Cause and Effect
Motivated Sequence
Attention
Need
Satisfaction
Visualization
Action