1. A tool for diagramming “informal” arguments
The Toulmin Model
A tool for diagramming
“informal” arguments

2. Stephen Toulmin The X’s and O’s of an argument
Stephen Toulmin, originally a British logician, was frustrated with the inability of formal logic to explain everyday arguments.
He developed his own model of practical reasoning.

3. the three basic elements:
Claim (assertion or proposition)
Grounds (proof, grounds, support)
Warrant (inferential leap or unexpressed premise)

4. Claims
A claim is the point an arguer is trying to make. The claim is the conclusion, proposition, or assertion an arguer wants another to accept.
The claim answers the question, "So what is your point?”
example: “Rosario is an American citizen, because she was born in the United States.”
example: “Barack Obama doesn’t wear a flag pin on his lapel, so he must not be patriotic.”

5. more about claims... There are four basic types of claims:
fact: claims which focus on empirically verifiable phenomena
judgment/value: claims involving opinions, attitudes, and subjective evaluations of things
policy: claims advocating courses of action that should be undertaken
definition/classification: indicates what criteria are being used to to define a term or what category something falls into

6. four types of claims
Fact: “Texas executes more inmates per year than any other state.”
Value or judgment:“Capital punishment is discriminatory.”
Policy: “Capital punishment should be abolished.”
Definition/Classification: “Capital punishment violates the 8th amendment’s prohibition against ‘cruel and unusual’ punishment.”

7. Grounds (proof or data)
Grounds refers to the proof or evidence an arguer offers.
Grounds can consist of statistics, quotations, reports, findings, physical evidence, or various forms of reasoning
example: “I’m a vegetarian. One reason is that I feel sorry for the animals. Another reason is for my own health.”
example: “I made the dinner, so you can do the dishes.

8. more about grounds...
Grounds are the support the arguer offers on behalf of his/her claim. The grounds answer questions such as:
"What is your proof?“
"How do you know?“
"Why?”
example: “It looks like rain. The barometer is falling.”
example: "The other Ritz Carlton hotels I've stayed at had great pools, so I'll bet this one has a great pool too."

9. still more about grounds...
grounds can be based on:
evidence: facts, statistics, reports, or physical proof
source credibility: authorities, experts, celebrity endorsers, a close friend, or someone's say-so
analysis and reasoning: reasons may be offered as proof
premises already held by the listener

10. clue words for identifying grounds
The grounds for an argument often follow words such as “because,” “since,” “given that…”
example: “Airports should x-ray all luggage because a bomb could be placed in a checked bag.”
example: “I expect to do well on the test, since I studied all night for it.”

11. multi-grounded arguments
A single claim may be supported by multiple grounds
Sonia: “My last dinner date was a disaster. The guy was wearing camouflage pants, talked about his old girlfriend the whole time, ate food off my plate without asking, and both of his credit cards were declined.”
Gigi: “No way!”
Sonia: “Guess who paid? Not Mr. Overdrawn.”
Gigi: “You should try an online dating service. You’ll have a bigger selection of guys to meet, you can screen out losers without having to meet them face to face, and it’s a lot safer.”

12. Warrants
The warrant is the inferential leap that connects the claim with the grounds.
The warrant is typically implicit (unstated) and requires the listener to recognize the connection between the claim and grounds
The implicit nature of warrants means the “meaning” of an argument is as much a part of the receiver as it is a part of the message.

13. the warrant connects the claim and grounds
Analogy of a stone arch.
The interlocking stones work together to support the arch.
The warrant is analogous to the keystone.
The claim and grounds are analogous to the voussoirs that form the curved portions of the arch.

14. more about warrants...
The warrant performs a "linking" function by establishing a mental connection between the grounds and the claim
example: “Muffin is running a temperature. I’ll bet she has an infection.”
example: "That dog is probably friendly. It is a Golden Retriever.”
(warrant: sign reasoning; a fever is a reliable sign of an infection)
(warrant: generalization; most or all Golden Retrievers are friendly)

15. making the right inferential leap
“There are newspapers piled up in the Boswell’s driveway driveway, so…
A. They probably have flu and are too ill to venture outside.
B. They are probably victims of foul play
C. They are illiterate
D. Their dog, that usually fetches the paper, died.
D. They are out of town for a few days

16. still more about warrants...
warrants can be based on:
authority: credible or admired sources
reasoning: analogy, sign, cause-effect, generalization
social norms: rude and polite behavior
ethical principles: moral guidelines
value premises: values shared by, or presumed to be shared by, the receiver(s)
folk wisdom, proverbs: look before you leap, a stitch in time saves nine.
pathos: emotional or motivational appeals
note: these categories aren't mutually exclusive, there is considerable overlap among the three

17. multi-warranted arguments
Some arguments are “multi-warranted,” e.g., based on more than one inferential leap
Surgeon General’s warning on a pack of cigarettes

18. the first triad sample argument 1
The Angels are likely to win the ballgame today
They are playing
at home
Claim
Grounds
Warrant
(unstated) generalization: The home team enjoys an advantage in baseball

19. the first triad sample argument 2
It was nominated for 10 Academy Awards
“Slumdog Millionaire” is a wonderful movie.
Claim
Grounds
Warrant
(unstated) sign reasoning: a movie’s greatness can be measured in the number of Oscar nominations it receives

20. the first triad sample argument 3
Biff was probably in a fight
He has a black eye
Claim
Grounds
Warrant
(unstated) sign reasoning: A black eye is a reliable indicator that a person has been in a fight

21. the first triad sample argument 4
She was the CEO of a major company, eBay.
Meg Whitman would make a great governor
Claim
Grounds
Warrant
(unstated) analogy: skills and practices that are effective in the private sector are also effective in the public sector.

22. the first triad sample argument 5
If you surf at Huntington Beach right after it rains you risk getting a bacterial infection
Runoff from the rain washes bacteria into the ocean
Claim
Grounds
Warrant
(unstated) cause-effect reasoning: bacteria in the water causes surfers to get ill.

23. Limitations regarding the Toulmin model
The Toulmin model offers a somewhat static view of an argument
Focuses on the argument maker, not the target or respondent
Real-life arguments aren’t always neat or clear
The Toulmin model is an analytical tool
Useful for dissecting arguments before or after they’ve been made
Not as useful, practical in the “heat” of an argument
Since warrants are unstated, different listeners may perceive them differently

24. Name that triad
Lyle comes from a large family, so he is probably a Catholic or a Mormon.
Dolphins give live birth, so they must be mammals.
Banning same sex marriages makes no sense. Being gay is simply a part of natural variation. If we don’t ban left-handers from marrying, or people with curly hair, why ban gays from marrying?
If you are going to the beach you’d better where sunblock or you’ll get skin cancer.