INFORMAL FALLACIES

The aim of this tutorial is to help you learn to recognize and resist fallacious arguments.

Fallacies are dangerous

Fallacies, or flawed arguments, are often used by cult recruiters on college campuses to target freshmen.

Critical thinking is the antidote to fallacious arguments. By recognizing fallacies and other types of flawed arguments, we can protect ourselves against those seeking to control or manipulate us.

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Fallacies: formal and informal

An argument is the process of supporting a claim by providing reasons or evidence for that claim. An argument contains a fallacy when it appears to be initially correct, but upon further examination is found to be incorrect.

In formal fallacies, the form of the argument itself is invalid.

An informal fallacy is mistaken reasoning that occurs when an argument is psychologically or emotionally persuasive but logically incorrect.

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Hot or Not?

Is the use of fallacies a legitimate political campaign tactic?

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Fallacies of ambiguity

Arguments that contain ambiguous words or phrases, sloppy grammar, or confusion between two closely-related concepts can lead to fallacies of ambiguity.

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Fallacies of ambiguity (continued)

Four types of fallacies of ambiguity: Equivocation occurs when a key term in an argument is

ambiguous—when it has more than one meaning. Amphiboly occurs when an argument contains a grammatical

mistake. Fallacies of accent occur when an argument’s meaning changes

depending on which words or phrases are emphasized. Fallacies of division occur when we make erroneous inferences

from group characteristics about those of individuals within the group.

Fallacies of composition occur when a characteristic of a member of a group is erroneously assumed to be characteristic of the whole group.

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Tiger Woods is a good golfer, therefore Tiger Woods is a good husband.

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Men are taller than women. Danny DeVito is a man.

Therefore, Danny DeVito is taller than the average woman.

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Fallacies of relevance

In fallacies of relevance, one or more of the premises is logically irrelevant, or unrelated, to the conclusion.

Fallacies of relevance include personal attacks or ad hominem fallacies; appeals to force or scare tactics; appeals to pity; popular appeals; appeals to ignorance; hasty generalizations; straw man fallacies; and red herrings.

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Ad hominem and appeal to force

The ad hominem fallacy occurs when we disagree with another’s conclusion and attack them personally instead of presenting a valid counter-argument.

The appeal to force fallacy occurs when we use or threaten to use force in an attempt to get others to back down or accept our conclusions.

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The ad hominem fallacy may occur between people in personal relationships.

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Darwin’s descent from the apes

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Appeal to pity and popular appeal

The appeal to pity fallacy occurs when we try to evoke feelings of pity in others when pity is irrelevant to the conclusion.

The fallacy of popular appeal occurs when we appeal to popular opinion to gain support for our conclusion. Two types of this fallacy include the bandwagon approach and the snob approach.

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The appeal to pity on this billboard is not fallacious.

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“I shouldn’t get a ticket because everyone speeds.”

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Appeal to ignorance and hasty generalization

The appeal to ignorance fallacy occurs when we try to argue something is true because no one has proven it false.

The fallacy of popular appeal occurs when we generalize from a sample that is too small or biased.

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Hot or Not?

Does celebrity endorsement of a product make you more likely to buy that product?

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“You’ve come a long way, baby.”

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“I want to be like Victoria Beckham, so I’ll buy the type of purse she is carrying.”

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Straw man and red herring fallacies

The straw man fallacy occurs when a person distorts or misrepresents the opponent’s argument, making it easier to knock down or refute.

The red herring fallacy occurs when a person tries to sidetrack an argument by going off on a tangent and bringing up a different issue directed toward a different conclusion.

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Rhetoric

When we start with a position statement, rather than with an open-ended question that invites exploration and analysis of an issue, we are using rhetoric.

Rhetoric, also known as the art of persuasion, is used to promote a particular position or worldview.

Although it has its uses, rhetoric becomes a problem when it is substituted for unbiased research and logical argumentation. When using rhetoric this way, people only present claims that support their own position.

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Argumentation

Whereas the purpose of rhetoric is to persuade people of what you consider to be the truth, the purpose of argumentation is to discover the truth.

Unlike rhetoric, arguments are open to multiple perspectives.

Good arguments provide evidence and reasons and invite feedback analysis.

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Fallacies involving unwarranted assumptions

Fallacies involving unwarranted assumptions occur when an argument includes an assumption that is not supported by evidence.

Fallacies involving unwarranted assumptions include begging the question, inappropriate appeal to authority, loaded question, false dilemma, questionable cause, slippery slope, and the naturalistic fallacy.

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Begging the question and inappropriate appeal to authority

The begging the question fallacy occurs when an argument’s conclusion is simply the rewording of its premise. This fallacy is also known as circular reasoning.

The inappropriate appeal to authority fallacy occurs when we look to an authority in a field that is unrelated or not under investigation.

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A uniform gives the idea that the person is an authority in fields that may be beyond his or her expertise.

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Loaded question and false dilemma

The loaded question fallacy occurs when a question is asked that assumes a particular answer to another unasked question.

The false dilemma fallacy reduces responses to complex issues to an either/or choice. By doing so, this fallacy polarizes stands on issues and ignores common ground or other solutions.

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It’s not a choice of only oil or alternative energies.

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Questionable cause and slippery slope

The questionable cause or post hoc fallacy occurs when a person assumes, without sufficient evidence, that one thing is the cause of another.

According to the slippery slope fallacy, if we permit a certain action, then all actions of this type, even extreme ones, will soon be permissible.

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Babe Ruth jinxed the Red Sox in 1920. Their World Series win in 2004 was attributed to

“the end of the curse.”

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The naturalistic fallacy

The naturalistic fallacy is based on the unwarranted assumption that what is natural is good or morally acceptable and that what is unnatural is bad or morally unacceptable.

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Same-sex parents are often discriminated against because many people only see “parents” as a mother and father.

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Strategies for avoiding fallacies

Once you have learned to identify informal fallacies, the next step is to develop strategies to avoid them.

The following strategies are recommended: Know yourself and the fallacies you are most

susceptible to. Build your self-confidence and self-esteem. Cultivate good listening skills; study others’ arguments

for fallacies. Avoid ambiguous, vague terms and faulty grammar.

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More fallacy avoidance strategies

Avoid confusing the soundness of an argument with the character or circumstances of the person making the argument.

Know your topic. Do your research. Adopt a skeptical “default” position. Watch your body language. Avoid inflammatory actions. Don’t be set on winning every argument. Seek the truth,

not victory.

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Conclusions

Use of fallacies in communication can damage relationships and impair sound critical thinking.

Identification and avoidance of fallacies through the use of effective strategies can improve our relationships with others and increase the credibility of our arguments.

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Perspectives on going to war in Iraq

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