English 1A
Instructor: «GreetingLine»
Evaluating Arguments
Toulmin’s Model of Arguments
Stephen Toulmin, a 20th century British philosopher, developed a model for evaluating
arguments. This is a simplified version of his model.
The three major elements of Toulmin’s argument model are:
Claim – the statement, position, or idea that the author wants the reader to accept.
Example: Congress should pass a law banning the sales and operation of most SUVs.
Evidence / data – the facts, examples, authoritative opinions, statistics, etc. that the author
presents to support the claim
Example: Studies show that SUVs emit significant levels of greenhouse gases.
Reason / warrant – the reasoning or logical connection between the evidence and the claim. The
reason explains how or why the evidence proves or supports the claim.
Example: Greenhouse gases contribute to global warming.
Claim: Evidence:
Congress should pass a Studies show that SUVs
law banning the sales and emit significant levels of
operation of most SUVs. greenhouse gases.
Reason:
Greenhouse gases, emitted by
SUVs, contribute to global
warming.
Aristotle’s categories for basic appeals in arguments:
Emotional appeals play to the reader’s feelings and values.
Example: In an argument for health care reform, the writer presents a story about one
family suffering under the current system that evokes the reader’s sympathy and sense of
fairness.
Ethical appeals seek to establish the credibility of the writer as trustworthy.
Example: The writer cites a source that the reader trusts; the writer gives the reader a
sense that complete facts are being presented and/or all sides of an issue are being treated
fairly.
Logical appeals use reasoning and logic to make their points.
Example: The writer makes a strong logical connection between the claim and the
evidence.
English 1A
Instructor: «GreetingLine»
Identifying and Fixing Errors in Arguments
Example 1
Claim: Smoking should be banned in all public spaces.
Reason/Warrant: Smoking is a serious health hazard.
Evidence: Studies show high cancer rates in people exposed to moderate to frequent secondhand
smoke in enclosed spaces.
Error 1: The evidence does not support the reason. The scope of the reason is too broad.
Example 1, Revision 1
Claim: Smoking should be banned in all public spaces.
Reason/Warrant: Secondhand smoke is a serious health hazard.
Evidence: Studies show high cancer rates in people exposed to moderate to frequent secondhand
smoke in enclosed spaces.
Error 2: The evidence still does not support the broadness of the reason and the claim.
Example 1, Revision 2
Claim: Smoking should be banned in all enclosed public spaces.
Reason/Warrant: Secondhand smoke in enclosed places is a serious health hazard.
Evidence: Studies show high cancer rates in people exposed to moderate to frequent secondhand
smoke in enclosed spaces.
Example 2
Claim: Business schools should increase their recruitment of women students.
Reason/Warrant: Women continue to face discrimination in the business world.
Evidence: Studies show women business executives are paid significantly less than equally
qualified males.
Error: Reason and evidence do not support claim.
Example 2, Revision 1
Claim: Despite significant progress, the women’s movement has not yet achieved equality for
women in the workplace.
Reason/Warrant: Women continue to face discrimination in the business world.
Evidence: Studies show women business executives are paid significantly less than equally
qualified males.
Test your claim and reason! It should make sense when you say, “(Your claim) because
(reason).”
Example 1: Business schools should increase their recruitment of women students because
women continue to face discrimination in the business world. (Statement does NOT make sense.)
Example 2: Despite significant progress, the women’s movement has not yet achieved equality
for women in the workplace because women continue to face discrimination in the business
world. (This statement makes sense.)