deductive and inductive arguments

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Argumentation
is a reasoned, logical way of asserting the soundness of a position, belief, or conclusion. It takes a stand – supported by evidence – and
urges people to share the writer’s perspective and insights.
Several purposes of argumentation
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To convince other people to accept – or at least acknowledge the validity of – your position
To defend your position, even if others cannot be convinced to agree
To question or refute a position you believe is misguided, untrue, dangerous, or evil, without necessarily offering an alternative
The difference in persuasion and argumentation
Persuasion refers to the method by which a writer moves an audience to adopt a belief or course of action. To persuade an
audience, a writer relies on various appeals – to emotions, to reason, to ethics.
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Logical/rational appeal (logos) - based on rational arguments that support sets of assumptions already accepted by the audience
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Emotional appeal (pathos) - based on acknowledgement of audience’s sympathies and beliefs and shows how the argument
relates to the audience
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Ethical appeal (ethos) - based on shared moral values and call upon an audience’s sense of right, justice, and virtue
Argumentation is the appeal to reason (logic) – connecting a series of statements so they lead logically to a conclusion.
Argumentation does not try to move an audience to action; its primary purpose is simply to demonstrate that certain ideas are valid
and others are not. Unlike persuasion, argumentation has a formal structure that involves making points, supplying evidence,
establishing a logical chain of reasoning, refuting opposing arguments, and accommodating the views of an audience. Some effective
arguments include an appeal to emotion to support and reinforce the logical appeal.
Writing an argument
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2.
Choose a topic
Take a stand
a. Thesis must be debatable (there is no point in arguing a position that most people already accept)
b. Test suitability of thesis by stating the antithesis
Analyze your audience
a. What beliefs or opinions are your readers likely to have?
b. Is the audience likely to be friendly, neutral, or hostile to your thesis?
c. Assume that an informed and determined opposition is looking for holes in your argument
Gather and document evidence
a. Evidence can be facts or opinions. Facts are often more convincing when they are supplemented by opinions, or interpretation
of facts. However, not all opinions are equally convincing – experts are more convincing than people who are less informed.
b. Consider what kinds of evidence might change the minds of skeptical readers
c. Choose your evidence with three criteria in mind
i. Relevance – evidence should support your thesis and be pertinent to your argument
ii. Representation – it should represent the full range of opinions about your subject
iii. Sufficiency – you should include enough evidence to support your claims
d. Document your evidence. Documentation gives readers the ability to judge the sources that you cite and to consult them if they
wish. Common knowledge can be presented without documentation.
Dealing with opposition
a. Specifically address the obvious objections to your case. This part of an argument is called refutation and is essential to making
the strongest case possible.
b. Refute opposing arguments by showing they are unsound, unfair, or weak.
c. When an opponent’s argument is so compelling that is cannot be easily dismissed, you should concede its strength. This shows
you are a fair-minded person. If possible, identify the limitations of the opposing position and then move on.
3.
4.
5.
Rogerian Argument
is a strategy put forth by psychologist Carl Rogers that rejects the adversarial approach that characterizes many arguments. Rather than
attacking the opposition, Rogers suggests acknowledging the validity of opposing positions. Both parties negotiate to determine points of
agreement. By finding areas of agreement, a Rogerian argument reduces conflict and increases the chance that the final position will
satisfy all parties.
Guidelines for Rogerian Argument
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Begin by summarizing opposing viewpoints.
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Carefully consider the position of those who disagree with you. What are their legitimate concerns? If you were in their place,
how would you react?
Present opposing viewpoints fairly and accurately. Demonstrate your respect for the ideas of those who disagree with you.
Concede the strength of a compelling opposing argument.
Think of the concerns that you and your opposition share.
Demonstrate to readers how they will benefit from the position you are defining.
Moving from evidence to conclusion: deductive and inductive arguments
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Deductive reasoning proceeds from a general premise or assumption to a specific conclusion.
Inductive reasoning proceeds from individual observations to a more general conclusion
Deductive Arguments – Syllogisms
A syllogism consists of a major premise (a general statement), a minor premise ( a related by more specific statement), and a conclusion
(which is drawn from the two premises). Example:
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Major premise:
All Olympic runners are fast.
Minor premise:
Florence Griffith Joyner is an Olympic runner
Conclusion: Florence Griffith Joyner is fast.
When a conclusion follows logically from the major and minor premse, then the argument is said to be valid. If the syllogism is not logical,
the argument is not valid. If the form of the syllogism is incorrect (the minor premise is not related or more specific than the major
premise), the argument is invalid. Consider this example:
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Major premise: All dogs are animals.
Minor premise: All cats are animals.
Conclusion: All dogs are cats. (The minor premise is not more specific than the major premise.
Another error occurs when the minor premise refers to a term in the major premise that is undistributed (that is, it covers only some of the
items in the class it denotes). Example:
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Major premise: All dogs are animals
Minor premise: Ralph is an animal.
Conclusion: Ralph is a dog (Ralph could be human, a monkey, etc.)
In the major premise, dogs is the distributed term; it designates all dogs. The minor premise refers not to dogs but to animals, which is
undistributed (the major premise does not say that all animals are dogs).
Validity of argument does not necessarily mean that a conclusion is true. In order for a conclusion to be true, both the major and minor
premises must be true. Example:
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Major premise: All dogs are brown
Minor premise: My lab, Toby, is a dog.
Conclusion: Toby is brown. (Toby could be black, white, brown, etc.)
To be sound, a syllogism must be both logical and true.
Inductive Arguments
Unlike deduction, inductive arguments have no specific form and its conclusions are less definitive than syllogisms. The Scientific Method is
a form of inductive reasoning. First, you develop a tentative answer to the question (a hypothesis). Then, you gather evidence. Finally,
you use inference to form a conclusion based on the evidence.
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Question: How did the window get broken?
Hypothesis: Something was thrown into the house from outside.
Evidence: There is a baseball on the floow. The baseball is not a part of the décor of the room. Some children were playing
baseball outside this afternoon. The shattered glass is on the inside of the house. The children are no longer outside, but their
equipment is still there.
Conclusion: One of the children hit or threw the baseball through the window; then they all ran away.
Toulmin Logic
developed by Stephen Toulmin, is a method of structuring an argument according to the way arguments occur in everyday life. Toulmin
logic divides an argument into three parts: the claim, the grounds, and the warrant.
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The claim is the main point of the essay. Usually, the main point is the stated thesis, but sometimes it may be implied.
The grounds is the material a writer uses to support the claim. It can be evidence (facts or opinions) or appeals to emotion.
The warrant is the inference that connects the claim to the grounds. It can be a belief that is taken for granted, or an assumption
that underlies the argument.
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Claim: Carol should be elected class president.
Grounds: Carol is an honor student. She has a diverse group of friends and is well-liked by the body. She has a good
relationship with the adults.
Warrant: A person who is an honor student, with a diverse group of friends, is well-liked, and has a good relationship
with adults would make a good class president.
When you use Toulmin logic, you derive your claim inductively from facts and examples, and you connect the grounds and warrant to your
claim deductively.
Claims and Thesis Statements
A CLAIM is an assertion that requires support. It is what an argument tries to convince readers to accept. The central claim--the main point-is almost always stated explicitly in a THESIS STATEMENT like one of the following:
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A CLAIM ABOUT REALITY The war on drugs is not winnable because it cannot eradicate demand or the supply to meet it.
A CLAIM OF VALUE Drug abuse is a personal matter that should not be subject to law.
A CLAIM FOR A COURSE OF ACTION The United States must intensify its efforts to reduce production of heroin in
Afghanistan.
Usually, but not always, you'll state your thesis at the beginning of your essay, making a play for readers' attention and clueing them in to
your purpose. But if you think readers may have difficulty accepting your thesis until they've heard some or all of your argument, then you
might save the thesis statement for the middle or end.
Here are three examples:
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Today there is more pressure placed on students to do well [in school] .... This new pressure is what is causing the increase in
cheating. (Colleen Wenke, "Too Much Pressure")
Racial profiling is an ugly business .... But I'm not opposed to allowing--no, requiring--airlines to pay closer attention to passengers
who fit a terrorist profile, which includes national origin. (Linda Chavez, "Everything Isn't Racial Profiling")
[T]hose of us who are refugees and exiles must live with the double menace of being both possible victims and suspects,
sometimes with fatal consequences. Will America ever learn again how to protect itself without sacrificing a great many innocent
lives? So that my uncle did not die in vain, I truly hope so. (Edwidge Danticat, "Not Your Homeland")
ARGUMENT AND PERSUASION IN PARAGRAPHS
Writing About Television
This self-contained paragraph, written for The Bedford Reader, argues that TV news aims for entertainment at the expense of serious
coverage of events and issues. The argument here could serve a number of different purposes in full essays: For instance, in a paper
claiming that television is our least reliable source of news, the paragraph would give one cause of unreliability; or in an essay analyzing
television news, the paragraph would examine one element.
Television news has a serious failing: It's show business. Unlike a newspaper, its every image has to entertain the
average beer drinker. To score high ratings and win advertisers, the visual medium favors the spectacular: riots,
tornados, air crashes. Now that satellite transmission invites live coverage, newscasters go for the fast-breaking
story at the expense of thoughtful analysis. "The more you can get data out instantly," says media critic Jeff
Greenfield, "the more you rely on instant data to define the news." TV zooms in on people who make news, but,
to avoid boredom, won't let them argue or explain. (How can they, in speeches limited to fifteen seconds?) In
2007, as the United States increased its forces in Iraq, President Bush addressed Congress to explain the action.
His lengthy remarks were clipped to twenty seconds on one news broadcast, and then an anchorwoman digested
the opposition to a single line: "Democrats tonight were critical of the president's actions." During the last two
presidential elections, the candidates sometimes deliberately packaged bad news so that it could not be distilled
to a sound bite on the evening news--and thus would not make the evening news at all. Americans who rely on
television for their news (two-thirds, according to recent polls) exist on a starvation diet.
TOPIC SENTENCE: THE CLAIM
EVIDENCE:
EXPERT OPINION
FACTS AND EXAMPLES
STATISTIC
Writing in an Academic Discipline
Taken from a textbook on public relations, the following paragraph argues that lobbyists (who work to persuade public officials in behalf of
a cause) are not slick manipulators but something else. The paragraph falls in the textbook's section on lobbying as a form of public
relations, and its purpose is to correct a mistaken definition.
Although the public stereotypes a lobbyist as a fast-talking person twisting an elected official's arm to get special
concessions, the reality is quite different. Today's lobbyist, who may be fully employed by one industry or
represent a variety of clients, is often a quiet-spoken, well-educated man or woman armed with statistics and
research reports. Robert Gray, former head of Hill and Knowlton's Washington office and a public affairs expert
for thirty years, adds, "Lobbying is no longer a booze and buddies business. It's presenting honest facts and
convincing Congress that your side has more merit than the other." He rejects lobbying as being simply
"influence peddling and button-holing" top administration officials. Although the public has the perception that
lobbying is done only by big business, Gray correctly points out that a variety of special interests also do it. These
may include such groups as the Sierra Club, Mothers Against Drunk Driving, the National Association of Social
TOPIC SENTENCE: THE CLAIM
EVIDENCE:
EXPERT OPINION
FACTS AND EXAMPLES
Workers, the American Civil Liberties Union, and the American Federation of Labor. Even the American Society of
Plastic and Reconstructive Surgeons hired a Washington public relations firm in their battle against restrictions
on breast implants. Lobbying, quite literally, is an activity in which widely diverse groups and organizations
engage as an exercise of free speech and representation in the marketplace of ideas. Lobbyists often balance
each other and work toward legislative compromises that benefit not only their self-interests but society as a
whole. (Dennis L. Wilcox, Phillip H. Ault, and Warren K. Agee, Public Relations: Strategies and Tactics)
Assignment: Daniels editorial
Student Writer: Matt Daniels wrote the following editorial for his college newspaper. As you read:
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4.
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6.
What is Daniel’s thesis/claim?
Highlight the inductive reasoning in Matt’s argument.
Highlight, in a different color, the deductive reasoning in Matt’s argument. Write out the major premise, minor premise, and
conclusion (these may not be directly stated).
Does Matt appeal mainly to emotion, logic, or ethics? Give two examples to support.
How does Matt “deal with the opposition”?
Explain why you agree or disagree with Matt’s position.
An Argument against the Anna Todd Jennings Scholarship
Recently, a dispute has arisen over the “Caucasian-restricted” Anna Todd Jennings scholarship. Anna Jennings died in 1955, and her will established
a trust that granted a scholarship of up to $15,000 for a deserving student. Unfortunately, Jennings, who had certain racist views, limited her
scholarship to “Caucasian students.” After much debate with family and friends, I, a white, well-qualified, and definitely deserving student, have
decided not to apply for the scholarship. It is my view that despite arguments to the contrary, applying for the Anna Todd Jennings scholarship
furthers the racist ideas held by its founder.
First, the Anna Todd Jennings scholarship is a subtle but nonetheless dangerous expression of racism. It explicitly discriminates against African
Americans, Asians, Latinos, Native Americans, and others. By providing a scholarship for whites only, Anna Jennings frustrates the aspirations of
groups who until recently had been virtually kept out of the educational mainstream. On this basis alone, students should refuse to apply and
should actively work to encourage the school to challenge the racist provisions of Anna Todd Jennings’s will. According to one expert, such
challenges have been upheld by the courts: the striking down of a similar clause in the will of the eighteenth century financier Stephen Girard,
which limited admission to while male orphans, is just one example.
Second, the Anna Todd Jennings scholarship has corrupted the school’s financial aid office, which resulted in students being harmed by the
scholarship. The director of the financial aid office acknowledged that he knew about the racial restrictions of the scholarship but thought that
students should have the right to apply anyway. Unlike the director, students who applied for the Anna Todd Jennings scholarship were unaware of
its restrictions. The materials distributed by the financial aid office also gave no indication that the award was limited to Caucasians. Students were
required to fill out forms, submit financial statements, and forward transcripts. In addition to this material, all students were told to attach a recent
photograph to their application. Little did the applicants know that the sole purpose of this innocuous little picture was to distinguish whites from
nonwhites. By keeping the secret the scholarship’s restrictions, the school has put students in the position of unwittingly endorsing Anna Jennings’s
racism. Thus, both the school and the unsuspecting students have been in collusion with the administrators of the Anna Todd Jennings trust.
Finally, the Anna Todd Jennings scholarship has forced students to sacrifice their nonracist principles for financial need. A recent edition of the
school paper contained several letters saying that students should accept Anna Jennings’s scholarship money. One student said, “If we do no take
that money and use our education to topple the barriers of prejudice, we are giving the money to those who will use the money in the opposite
fashion.” This argument, although attractive, is flawed. If an individual accepts a scholarship with racial restrictions, then he or she is actually
endorsing the principles behind it. If a student does not want to appear to endorse racism, then he or she should reject the scholarship, even if this
action causes hardship or gives adversaries a momentary advantage. To do otherwise is to further the cause of the individual who set up the
scholarship. The best way to register a protest is to work to change the requirement for the scholarship and to encourage others not to apply as
long as the racial restrictions exist.
Another letter to this newspaper made the point that a number of other restricted scholarships are available at the school and no one seems to
question them. For example, one is for the children of veterans, another is for women, and yet another is earmarked for African Americans. Even
though these scholarships have restrictions, to assume that all restrictions are the same is to make a hasty generalization. Women, African
Americans, and the children of veterans are groups that many believe deserve special treatment. Both women and African Americans, and the
children of veterans are groups that many believe deserve special treatment. Both women and African Americans have been discriminated against
for years, and, as a result, educational opportunities have been denied them. Earmarking scholarships for them is simply a means of restoring some
measure of equality. The children of veterans have been singled out because their parents have performed an extraordinary service for their
country. Whites, however, do not fall into either of those categories. Special treatment for them is based solely on race and has nothing to do with
any objective standard of need or merit.
I hope that by refusing to apply for the Anna Todd Jennings scholarship, I have encouraged other students to think about the issues involved in their
own decisions. All of us have a responsibility to ourselves and to society. If we truly believe that racism in all its forms is evil, then we have to make
a choice between sacrifice and hypocrisy. Faced with these options, our decision should be clear: accept the loss of funds as an opportunity to
explore your values and fight for your principles; if you do, this opportunity is worth far more than any scholarship.
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