Logical Fallacies Continuing our foray into the world

Logical Fallacies Continuing our foray into the world of Argument Courtesy of: http: //www. unc. edu/depts/wcweb/handouts/fallacies. html

What is Fallacy? A fallacy is an error of reasoning. These are flawed statements that often sound true.

Hasty Generalization • Definition: Making assumptions about a whole group or range of cases based on a sample that is inadequate (usually because it is atypical or just too small). • Example: "My roommate said her philosophy class was hard, and the one I'm in is hard, too. All philosophy classes must be hard!"

Missing the Point Definition: The premises of an argument do support a particular conclusion--but not the conclusion that the arguer actually draws. Example: "The seriousness of a punishment should match the seriousness of the crime. Right now, the punishment for drunk driving may simply be a fine. But drunk driving is a very serious crime that can kill innocent people. So the death penalty should be the punishment for drunk driving

Post hoc (false cause) This fallacy gets its name from the Latin phrase "post hoc, ergo propter hoc, " which translates as "after this, therefore because of this. " • Definition: Assuming that because B comes after A, A caused B. • Examples: "President Jones raised taxes, and then the rate of violent crime went up. Jones is responsible for the rise in crime. “ • caused the other.

Slippery Slope Also known as “the Camel’s Nose • Definition: The arguer claims that a sort of chain reaction, usually ending in some dire consequence, will take place, but there's really not enough evidence for that assumption. • Example: "Animal experimentation reduces our respect for life. If we don't respect life, we are likely to be more and more tolerant of violent acts like war and murder. Soon our society will become a battlefield in which everyone constantly fears for their lives. It will be the end of civilization. To prevent this terrible consequence, we should make animal experimentation illegal right now. "

Weak Analogy • Definition: Many arguments rely on an analogy between two or more objects, ideas, or situations. If the two things that are being compared aren't really alike in the relevant respects, the analogy is a weak one, and the argument that relies on it commits the fallacy of weak analogy. • Example: "Guns are like hammers --they're both tools with metal parts that could be used to kill someone. And yet it would be ridiculous to restrict the purchase of hammers--so restrictions on purchasing guns are equally ridiculous. “

Appeal to Authority • Definition: Often we add strength to our arguments by referring to respected sources or authorities and explaining their positions on the issues we're discussing. • Example: "We should abolish the death penalty. Many respected people, such as actor Guy Handsome, have publicly stated their opposition to it. “

Appeal to Pity • Definition: The appeal to pity takes place when an arguer tries to get people to accept a conclusion by making them feel sorry for someone. • Example: "I know the exam is graded based on performance, but you should give me an A. My cat has been sick, my car broke down, and I've had a cold, so it was really hard for me to study!" • Example: "It's wrong to tax corporations--think of all the money they give to charity, and of the costs they already pay to run their businesses!"

Appeal to Ignorance • Definition: In the appeal to ignorance, the arguer basically says, "Look, there's no conclusive evidence on the issue at hand. Therefore, you should accept my conclusion on this issue. " • Example: There is intelligent life in outer space, for no one has been able to prove that there isn't. • I know that every action we perform is predetermined because no one has proved that we have free will.

Straw Man • Definition: One way of making our own arguments stronger is to anticipate and respond in advance to the arguments that an opponent might make. The arguer sets up a wimpy version of the opponent’s position and tries to score point by knocking it down.

Red Herring • Definition: Partway through an argument, the arguer goes off on a tangent, raising a side issue that distracts the audience from what's really at stake. Often, the arguer never returns to the original issue. • Example: "Grading this exam on a curve would be the most fair thing to do. After all, classes go more smoothly when the students and the professor are getting along well. ”

Whole and Parts Fallacy • assuming that something true of part of a whole must also be true of the whole • Human cells are invisible to the naked eye. • Humans are made up of human cells. • Therefore, humans are invisible to the naked eye. • Each cell is invisible , but the aggregate of these cells are not invisible.

False Dichotomy • Definition: In false dichotomy, the arguer sets up the situation so it looks like there are only two choices. The arguer then eliminates one of the choices, so it seems that we are left with only one option: the one the arguer wanted us to pick in the first place. • Example: "Caldwell Hall is in bad shape. Either we tear it down and put up a new building, or we continue to risk students' safety. Obviously we shouldn't risk anyone's safety, so we must tear the building down. "

Begging the Question • Definition: A complicated fallacy, an argument that begs the question asks the reader to simply accept the conclusion without providing real evidence • Also called circular logic • Examples: "Active euthanasia is morally acceptable. It is a decent, ethical thing to help another human being escape suffering through death. " Let's lay this out in premise-conclusion form: • Premise: It is a decent, ethical thing to help another human being escape suffering through death. • Conclusion: Active euthanasia is morally acceptable.

Is-Ought Fallacy • Claiming that something that ought to be actually is. • Claiming that something that is, means it ought to be. • Example: • The world is an orderly place. • Therefore there ought to be a source of that order. • A supreme creator ought to be orderly. Therefore the world is an orderly place

Can you name this Fallacy? • Cheating by the Soviets • Barry Schweid of the Associated Press, in his efforts to criticize President Reagan's space-based defense against Soviet missiles, came up with a report from some Stanford University group that claimed to find little evidence of cheating by the Soviet Union on arms-control treaties. • Where were they when Secretary of Defense Caspar Weinberger and George Shultz, secretary of state, and several members of our military forces went on TV and described and enumerated the different times and ways that the Soviet Union has cheated on the 1972 Anti-Ballistic Missile Treaty? • Does Schweid really believe that the group at Stanford is more knowledgeable about U. S. arms-control policy than all our military experts, with Congress thrown in for good measure? If I thought that was true, I wouldn't sleep much tonight. And I doubt if he would either. • Appeal to authority

Equivocation = = • Definition: Equivocation is sliding between two or more different meanings of a single word or phrase that is important to the argument. • Example: "Giving money to charity is the right thing to do. So charities have a right to our money. " • The equivocation here is on the word "right": "right" can mean both something that is correct or good (as in "I got the right answers on the test") and something to which someone has a claim (as in "everyone has a right to life"). • Sometimes an arguer will deliberately, sneakily equivocate, often on words like "freedom, " "justice, " "rights, " and so forth; other times, the equivocation is a mistake or misunderstanding. Either way, it's important that you use the main terms of your argument consistently.

Can you name this Fallacy? 1) It is ridiculous to have spent thousands of dollars to rescue those two whales trapped in the Arctic ice. Why look at all the people trapped in jobs they don’t like. RED HERRING

Name that Fallacy • Person A: I support the separation of church and state. • Person B: So you support godless athiest communism? See how well that worked out in Russia, China, and Cuba? • Strawman

Can you name this Fallacy? • Bill: "You know, those feminists all hate men. " Joe: "Really? " Bill: "Yeah. I was in my philosophy class the other day and that Rachel chick gave a presentation. " Joe: "Which Rachel? " Bill: "You know her. She's the one that runs that feminist group over at the Women's Center. She said that men are all sexist pigs. I asked her why she believed this and she said that her last few boyfriends were real sexist pigs. " Joe: "That doesn't sound like a good reason to believe that all of us are pigs. " Bill: "That was what I said. " Joe: "What did she say? " Bill: "She said that she had seen enough of men to know we are all pigs. She obviously hates all men. " Joe: "So you think all feminists are like her? " Bill: "Sure. They all hate men. “ • Hasty Generalization

Can you name this Fallacy? 2) Plagiarism is deceitful because it is dishonest. BEGGING THE QUESTION

Can you name this Fallacy? • Person A: Illinois is going to have to cut spending on education this year. • Person B: Why? • Person A: Well, its either cut education spending or borrow money and go deeper into debt, and we can't afford to go any deeper into debt. • False Dichotomy

Can you name this Fallacy? 3) Water fluoridation affects the brain. Citywide, student’s test scores began to drop five months after fluoridation began. POST HOC (false cause)

Can you name this Fallacy? 4) I know three redheads who have terrible tempers, and since Annabel has red hair, I’ll bet she has a terrible temper too. HASTY GENERALIZATION

Can you name this Fallacy? Appeal to pity

Can you name this Fallacy? Equivocation

Can you name this Fallacy? • [Joe Mc. Carthy] announced that he had penetrated "Truman's iron curtain of secrecy" and that he proposed forthwith to present 81 cases… Cases of exactly what? "I am only giving the Senate, " he said, "cases in which it is clear there is a definite Communist connection…persons whom I consider to be Communists in the State Department. " … Of Case 40, he said, "I do not have much information on this except the general statement of the agency…that there is nothing in the files to disprove his Communist connections. “ • Appeal to ignorance

Can you name this Fallacy? 5) Supreme Court Justice Byron White was an All-American football player while in college, so how can you say that athletes are dumb? HASTY GENERALIZATION

Can you name this Fallacy? 6) Why should we put people on trial when we know they are guilty? BEGGING THE QUESTION

Can you name this Fallacy? 7) You support capital punishment just because you want an “eye for an eye, ” but I have several good reasons to believe that capital punishment is fundamentally wrong… STRAW MAN

Can you name this Fallacy? 8) The meteorologist predicted the wrong amount of rain for May. Obviously the meteorologist is unreliable. HASTY GENERALIZATION

Can you name this Fallacy? 9) You know Jane Fonda’s exercise video’s must be worth the money. Look at the great shape she’s in. POST HOC (false cause)

Can you name this Fallacy? 10) We have to stop the tuition increase! The next thing you know, they'll be charging $40, 000 a semester! SLIPPERY SLOPE

Can you name this Fallacy? 11) The book Investing for Dummies really helped me understand my finances better. The book Chess for Dummies was written by the same author, was published by the same press, and costs about the same amount, so it would probably help me understand my finances as well. WEAK ANALOGY

Can you name this Fallacy? 12) Look, you are going to have to make up your mind. Either you decide that you can afford this stereo, or you decide you are going to do without music for a while. FALSE DICHOTOMY (Dilemma)

Can you name this Fallacy? 13) I'm positive that my work will meet your requirements. I really need the job since my grandmother is sick. APPEAL TO PITY

Can you name this Fallacy? 14) Crimes of theft and robbery have been increasing at an alarming rate lately. The conclusion is obvious, we must reinstate the death penalty immediately. MISSING THE POINT

Can you name this Fallacy? • Atoms are colorless. Cats are made of atoms, so cats are colorless. • Whole and Parts Fallacy

Can you name this Fallacy? 15) I'm not a doctor, but I play one on the hit series "Bimbos and Studmuffins in the OR. " You can take it from me that when you need a fast acting, effective and safe pain killer there is nothing better than Morphi. Dope 2000. That is my considered medical opinion. APPEAL TO AUTHORITY

Can you name this Fallacy? • Efforts to ban chlordane assailed • WASHINGTON (AP)--The only exterminator in Congress told his colleagues Wednesday that it would be a short-sighted move to ban use of chlordane and related termiticides that cause cancer in laboratory animals. • Supporters of the bill, however, claimed that the Environmental Protection Agency was "dragging its feet" on a chemical that could cause 300, 000 cancers in the American population in 70 years. • "This bill reminds me of legislation that ought to be introduced to outlaw automobiles" on the grounds that cars kill people, said Rep. Tom De. Lay, RTexas, who owns an exterminating business. • EPA banned use of the chemicals on crops in 1974, but permitted use against termites because the agency did not believe humans were exposed. Chlordane does not kill termites but rather drives them away. • Weak analogy