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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Ad hominem and appeal to force Ad hominem fallacy occurs when we disagree with another’s conclusion and attack them personally instead of presenting a valid counter-argument. 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Appeal to pity and popular appeal 8 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Appeal to ignorance and hasty generalization 9 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Straw man and red herring fallacies 10 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Begging the question and inappropriate appeal to authority 12 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Loaded question and false dilemma 13 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

Questionable cause and slippery slope 14 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

The naturalistic fallacy 15 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

More fallacy avoidance strategies 17 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.

© 2010, The McGraw-Hill Companies, Inc. All Rights Reserved. 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. © 2010, The McGraw-Hill Companies, Inc. All Rights Reserved.