1. Session 3: Building Arguments and Evidence
ECUST—CDEN
Workshop for Debate and
Public Speaking Teachers
June 3-5, 2016
Session 3: Building Arguments and Evidence

2. Basic Model of Communication
Speaker
Message
Audience

3. Basic Parts of an Argument
Claim: A clear and contestable statement about a topic
Evidence: Something to support the claim
Reasoning / Warrant: Something that explains how evidence supports the claim

4. Modeling an Argument The Toulmin Model
Evidence
Claim
Reasoning / Warrant

5. Argument Example Topic: Public speaking
Claim: In order to improve English proficiency, all ECUST students should be required to take a semester of English public speaking.
Evidence: Universities that require public speaking have higher test scores.
Reasoning / Warrant: What works at other universities is likely to work at ECUST.

6. Modeling an Argument
In order to improve English proficiency, all ECUST students should be required to take English public speaking.
Universities that require public speaking have higher test scores.
What works at other universities is likely to work at ECUST.

7. Thesis Statements More narrow than a topic Should be:
Clear
Contestable
Controversial
Compelling
How is a speech thesis different from a paper thesis?

8. Thesis Statement Poor Thesis: Public speaking classes are useful.
Good Thesis: Students should take public speaking classes because they are useful.
Better Thesis: ECUST students should take public speaking classes because they help build English proficiency.

9. Activity: Crafting a Thesis Statement
In groups:
Topic: Chinese students studying in the
United States
Create a thesis statement that is clear, contestable, and compelling for a persuasive speech about this topic

10. Activity: Crafting a Thesis Statement
If a student came to you with this thesis, how would you encourage them to improve it? Thesis: American college students should visit China.

11. Using Evidence Effectively
Purposes of Evidence:
To make a claim clear and concrete
To make a claim vivid
To show the truth of a claim
To present the speaker as credible

12. Sample Categories of Evidence
Stories
Analogies
Expert
Statistics
Visuals

13. Evidence: Stories Strengths Invite empathy and identification
Contribute to the credibility of the speaker
Weaknesses
May be unrepresentative
Can be easily dismissed

14. Enhance Power of a Story
Real stories have more rhetorical force than hypothetical ones
Offer more than one story
Compensate for the lonely example with statistical measures showing frequency or occurrence

15. Evidence: Analogies Strengths Can make a concept or problem vivid
Can crystallize an idea into a single phrase
Can make links between what is known and unknown
Weaknesses
In logical terms, gives no proof
Can seem irrelevant, be misunderstood

16. Enhance Power of Analogy
In general, an analogy is more powerful when there are many points of similarities between the items being compared.
Analogies also have greater force when they are fresh, original.

17. Evidence: Expert Testimony
Strengths
Can provide clear interpretation of complex data
Can enhance credibility of the speaker
Weaknesses
Often misused, fallacious
Can seem disconnected from audience experience

18. Enhance Power of Expert Testimony
Demonstrate that the authority figure has expertise on the topic: Use experts who have access to the necessary info, are qualified to interpret that information, are acknowledged as experts on the subject.
Contrast the generalizations of an expert with examples of testimony, stories from people who have experienced the problem.

19. Evidence: Statistics Strengths
Can be logically strong because they are measures of frequency
Give appearance of objectivity and precision
Weaknesses
Statistics can be used to distort and misrepresent
Statistics can be impersonal, difficult to remember

20. Enhance Power of Statistics
Transform statistics into proportions and relationships that are within our personal experience.
Compensate for the impersonality of statistics by connecting them to a story
Compensate for the complexity of statistics with a visual aid
Compensate for the complexity of data with interpretation of experts

21. Evidence: Visuals Strengths Package ideas quickly and holistically.
Simplify complex ideas and engage readers.
Weakness
Can oversimplify and thus distort issues because they lack context.
Can be distracting
Can be misinterpreted

22. Enhance Power of Visuals
Compensate for the risk of distraction by keeping it simple. Don’t show competing images.
Compensate for the risks of distortion and misinterpretation by providing context and direction: point out what you want the audience to note about the visual (especially graphs)

23. Selecting Evidence for Arguments
Class activity: 1. Select an argument (from list provided) 2. Decide what type(s) of evidence you would use to make the argument to this audience; explain why you would choose to use that kind of evidence.

24. Analysis of Evidence What is the main idea (claim) of the speech?
What do you think is the most effective form of evidence used by the speaker and why?
If you were advising the speaker, what if anything would you suggest he do to strengthen his use of evidence?