The Toulmin Model
A tool for diagramming
“informal” arguments
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.
the three basic elements:
• Claim (assertion or proposition)
• Grounds (proof, grounds, support)
• Warrant (inferential leap or unexpressed
premise)
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.”
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
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.”
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.
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."
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
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.”
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.”
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.
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.
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.”
(warrant: sign reasoning; a fever is a reliable sign of an
infection)
– example: "That dog is probably friendly. It is a Golden
Retriever.”
(warrant: generalization; most or all Golden
Retrievers are friendly)
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
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
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
the first triad
sample argument 1
The Angels are likely to
win the ballgame today
They are playing
at home
Grounds
Claim
Warrant
(unstated) generalization:
The home team enjoys an
advantage in baseball
the first triad
sample argument 2
It was nominated
for 10 Academy
Awards
“Slumdog Millionaire” is a
wonderful movie.
Grounds
Claim
Warrant
(unstated) sign reasoning: a
movie’s greatness can be
measured in the number of
Oscar nominations it receives
the first triad
sample argument 3
Biff was probably in a
fight
Claim
He has a black eye
Grounds
Warrant
(unstated) sign reasoning: A
black eye is a reliable
indicator that a person has
been in a fight
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.
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.
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
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.