Fallacies Flaws in the Structure of an Argument
What are fallacies? • Fallacies are defects in an argument. • Fallacies cause an argument to be invalid, unsound, or weak. • Fallacies can be separated into two general groups: formal and informal.
Formal Fallacies • Formal fallacies are only found in deductive arguments. • Deductive arguments are supposed to be air-tight. • For a deductive argument to be valid, it must be absolutely impossible for both its premises to be true and its conclusion to be false. With a good deductive argument, that simply cannot happen; the truth of the premises entails the truth of the conclusion.
Formal Fallacies • The classic example of a deductively valid argument is: • 1. All men are mortal. (premise) • 2. Socrates is a man. (premise) • 3. Therefore Socrates is mortal. (guaranteed conclusion) • It is simply not possible that both (1) and (2) are true and (3) is false, so this argument is deductively valid.
Formal Fallacies • Any deductive argument that fails to meet this very highstandard commits a logical error, and so, technically, is fallacious. • This includes many arguments that we would usually accept as good arguments, arguments that make their conclusions highly probable but not certain. • Arguments that aren’t deductively valid are said to commit a “formal fallacy.”
Formal Fallacies • Example of a deductive argument with a formal fallacy: 1. All humans are mammals. (premise)2. All cats are mammals. (premise)3. All humans are cats. (conclusion) • Both premises in this argument are true but the conclusion is false. The defect is a formal fallacy and can be demonstrated by reducing the argument to its bare structure: 1. All A are C2. All B are C3. All A are B
Formal Fallacies • With deductive arguments, it can be helpful to reduce an argument to its structure. • All chickens are feathered animals. (premise) • Clucko is a chicken. (premise) • Therefore Clucko is a feathered animal. (guaranteed conclusion)
Formal Fallacies • All chickens are feathered animals. (premise) • Quacko is a feathered animal. (premise) • Therefore Quacko is a chicken. (non-guaranteed conclusion) • This argument commits a formal fallacy in that its form doesn’t guarantee the truth of its conclusion, even if the initial premises are true.
The Problem of Conclusiveness in an Argument • Real-world arguments address contestable issues of truth and value that cannot be resolved with mathematical certainty. • Disputants can create only more or less persuasive arguments, never conclusive ones.
Informal Fallacies • They are flaws in the structure of an argument. • They are embedded in many everyday arguments. • They sometimes make fallacious reasoning seem deceptively persuasive
Why Study Informal Fallacies? • Knowledge of informal fallacies is most useful when we run across arguments that we “know” are wrong, but we cannot quite say why. • Knowledge of informal fallacies can help you locate specific weaknesses in others’ arguments . . . and in your own!
Warning! • Most students who study fallacies begin to find them plentiful in the arguments of those with whom they disagree. • Realize that fallacies are most likely being used with equal frequency by you, as well as your friends. • Test your integrity by diligently seeking fallacies in your own arguments.
Informal Fallacies: Three Categories • Fallacies of Pathos • Fallacies of Ethos • Fallacies of Logos
Fallacies of Pathos • Rest on flaws in the way an argument appeals to the audience’s emotions and values • Argument to the People • Appeal to Ignorance • Appeal to Popularity • Appeal to Pity • Red Herring
Argument to the PeopleAppeal to Stirring Symbols • Appeal to the fundamental beliefs, biases, and prejudices of the audience in order to sway opinion through a feeling of solidarity among those of a group.
Argument to the PeopleAppeal to Stirring Symbols • The stirring symbol of the American flag • Allegiance to nationalistic values • Solidarity of American citizens • Ex: Joe Politician delivering a speech while wearing a suit made out material patterned with the American flag. • Ex: Marilyn Manson wiping his butt on an American flag.
Appeal to Ignorance • Presenting assumptions, assertions, or evidence that the audience is incapable of examining or judging. • Maintaining that because a claim has not been disproved, it must be true.
Appeal to Ignorance • Ex: Researchers have not conclusively shown that there is no monster at the bottom of Loch Ness; therefore, we should expect to see the monster at any time. • Ex: There must be intelligent life on other planets. No one has proven that there isn’t.
Appeal to Ignorance • Ex: Genetically modified organisms must be dangerous to our health because science has not proved that they are safe. • Ex: Jones must have used steroids to get those bulging muscles because he cannot prove that he has not used steroids.
Appeal to PopularityThe Bandwagon Appeal • The argument rests on the assertion that since everybody else is doing something, you should do it too. • These appeals are fallacious because the popularity of something is irrelevant to its actual merits. • These appeals are common in advertising where the claim that a product is popular substitutes for evidence of the product’s excellence.
Appeal to PopularityThe Bandwagon Appeal • Ex: All the popular, cool kids have tattoos; therefore, I should get a tattoo. • Ex: Everybody who has a Facebook page has a lot of friends; therefore, I should make a Facebook page.
Appeal to PopularityThe Bandwagon Appeal • Ex: Living together before marriage is the right thing to do because most couples are now doing it. • Ex: You should buy a Toyota Camry because itis the best-selling car in the world.
Appeal to Pity • The arguer appeals to the audience’s sympathetic feelings in order to support a claim that should be decided on more relevant or objective grounds.
Appeal to Pity • Ex: “Professor Rose, I’m sorry I couldn’t finish my essay. You don’t understand how difficult my life is right now. My parents could not afford to send me to college, and I have to work two part-time jobs to pay for my classes and books.”
Appeal to Pity • Ex: “Honorable Judge, I should not be fined $250 for driving 85 mph in a 25 mph zone because I was distraught from hearing the news of my brother’s illness and was rushing to see him in the hospital.”
Red Herring • Refers to the practice of throwing an audience off track by raising an unrelated or irrelevant point. • The name derives from the practice of using a red herring (a very smelly fish) to throw dogs off from a scent that they are supposed to be tracking.
Red Herring • Ex: Jack’s girlfriend asks, “Where were you last night?” Jack answers, “I sure am glad to see you. You look extra beautiful today!” • Ex: Question to politician, “What’s your stand on gun control?” Politician’s reply, “I’m for family values.”
Red Herring • Ex: I don’t believe we should elect this candidate because she would have to put her children in daycare.
Fallacies of Ethos • Fallacies of Ethos = Rest on a flawed relationship between the argument and the character of those involved in the argument. • Often these fallacies attack character or use character instead of evidence for proof.
Appeal to False Authority • The arguer appeals to the authority of a popular person rather than a knowledgeable one. • Many advertisements are based on this fallacy. • Testimony to support an argument should come from a person competent in the field.
Appeal to False Authority • Kobe Bryant says that Wheaties cereal keeps him on his game; therefore, Wheaties cereal is a good cereal. • Real evidence about the quality of Wheaties cereal would include specific information about its nutritional content rather than testimony from a hired athlete.
Appeal to False Authority • My favorite actor, who appeared in a movie about AIDS, has testified that the HIV virus doesn’t really cause AIDS and that there has been a cover-up. So, I think that AIDS must be caused by something other than HIV, and the drug companies are hiding it so that they can make money from expensive anti-HIV drugs. • The above argument bases its conclusion on the testimony of an actor, apparently because he appeared in a movie on the topic. Legitimate testimony on the nature of AIDS would have to come from doctors or scientists.
Appeal to False Authority • Tom Cruise says that postpartum depression can be best treated with vitamins because anti-depressant drugs are dangerous. Therefore, all women who claim they have postpartum depression should stop taking anti-depressants and start taking vitamins.
Ad HominemAppeal to the person • Arguments that attack the character of the arguer rather than the argument itself • Name-calling (referring to a disputant by unsavory names) • Appeal to prejudice (applying ethnic, racial, gender, or religious slurs to an opponent) • Guilt by association (linking the opposition to extremely unpopular groups or causes) • Poisoning the Well (discrediting an opponent or an opposing view in advance)
Ad HominemAppeal to the person • Name-calling • Ex: OJ Simpson claims that he is innocent, but he’s a wife beater. • Ex: Hugh Hefner, founder of Playboy magazine, has argued against the censorship of pornography. But Hefner is an immature, self-indulgent millionaire who never outgrew the adolescent fantasies of his youth. His argument is worthless. • Ex: All wars are not wrong. The people who say so are cowards.
Ad HominemAppeal to the person • Appeal to prejudice • Ex: Because he is extremely wealthy, our mayor cannot properly represent this city. • Ex: I reject what Father Rolly has to say about the ethical issues of abortion because he is a Catholic priest. After all, Father Rolly is required to hold such views. • Ex: Of course she is in favor of Affirmative Action. What do you expect from a black woman?
Ad HominemAppeal to the person • Guilt by Association • Ex: Of course you support medical marijuana. All of your friends are a bunch of pot-head hippies. • Ex: Professor Smith has argued against the theory of evolution. But he’s a member of the Communist Bikers’ Association. I refuse to listen to him!
Ad HominemAppeal to the person • Poisoning the Well • Ex: You are told, prior to meeting him, that your friend’s boyfriend is a poseur and a mooch. When you meet him, everything you hear him say is tainted. • Ex: Before I leave the floor to the next speaker, I must remind you that persons who oppose my plan do not have the best interests of the working people in their hearts.
Straw Man • Greatly oversimplifying an opponent’s argument in order to make it easier to refute or ridicule • Diverts attention from the real issue • The name comes from the practice of stuffing dummies and scarecrows with straw. When one attacks an opponent by putting words into the opponent’s mouth, one makes up a “dummy” position. But just as beating up a scarecrow doesn’t demonstrate any athletic accomplishment, beating up a “straw man” in an argument doesn’t demonstrate anything.
Straw Man • Ex: You many think that levying confiscatory taxes on homeless people’s cardboard dwellings is the surest way out of a recession, but I don’t. • Ex: While my opponent would like to empty our prisons of serial killers, I hold to the sacred principles of compensatory justice.
Fallacies of Logos • Rest on flaws in the relationship among statements in an argument
Hasty Generalization • Making a broad generalization on the basis of too little evidence • Traditionally, faulty generalizations have been labeled either “hasty” or “unrepresentative.”
Hasty Generalization • Ex: Yesterday I met the most remarkable person. He is kind, considerate, sensitive, and thoughtful. • Ex: I talked to five people in my neighborhood, and all of them said they had guns. The whole city must be armed.
Hasty Generalization • Ex: My cousin is a college student, and he doesn’t care the least bit about politics. Students these days are terribly apathetic. • Ex: Jean writes poetry, and she’s very sensitive and frequently depressed. People who write poetry are sensitive and prone to depression.
Post Hoc, Ergo Propter HocAfter This, Therefore Because of This • Occurs when a sequential relationship is mistaken for a causal relationship • Confusing correlation for cause • Ex: Event A occurred before Event B; therefore, Event A must have caused Event B.
Post Hoc, Ergo Propter HocAfter This, Therefore Because of This • Ex: Governor X took office in 2008. In 2009, the state suffered a severe recession. Therefore, Governor X should not be re-elected. • Ex: Cramming for a test really helps. Last week I crammed for a psychology test, and I got an A on it.
Post Hoc, Ergo Propter HocAfter This, Therefore Because of This • Superstition is often based on this fallacy. • Ex: Since I walked under that ladder yesterday, I’ve lost my wallet and received a speeding ticket. • Ex: Everything was going fine until the lunar eclipse last month; that’s why the economy is in trouble.
Begging the QuestionCircular Reasoning • Supporting a claim with a reason that simply restates the claim in different words • Ex: Bungee-jumping is dangerous because it’s unsafe. • Ex: Women should not be permitted to join men’s clubs because the clubs are for men only.
Begging the QuestionCircular Reasoning • Ex: Abortion is murder because it is the intentional taking of the life of a human being. • Because “murder” is defined as the “intentional taking of the life of a human being,” the argument is circular.