Common Logical Fallacies

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Common Logical Fallacies by Mind Map: Common Logical Fallacies

1. 15. Equivocation

1.1. Example

1.1.1. "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")

1.2. Definition

1.2.1. Equivocation is sliding between two or more different meanings of a single word or phrase that is important to the argument.

2. 14. Begging the question

2.1. Example

2.1.1. "Active euthanasia is morally acceptable. It is a decent, ethical thing to help another human being escape suffering through death."

2.2. Definition

2.2.1. A complicated fallacy; it comes in several forms and can be harder to detect than many of the other fallacies we've discussed.

3. 13. False dichotomy

3.1. Example

3.1.1. "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."

3.2. Definition

3.2.1. 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

4. 12. Red herring

4.1. Example

4.1.1. "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."

4.2. Definition

4.2.1. 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.

5. 11. Straw man

5.1. Example

5.1.1. "Feminists want to ban all pornography and punish everyone who reads it! But such harsh measures are surely inappropriate, so the feminists are wrong: porn and its readers should be left in peace."

5.2. Definition

5.2.1. One way of making our own arguments stronger is to anticipate and respond in advance to the arguments that an opponent might make. In the straw man fallacy, the arguer sets up a wimpy version of the opponent's position and tries to score points by knocking it

6. 10. Appeal to ignorance

6.1. Example

6.1.1. "People have been trying for centuries to prove that Monsters exists. But no one has yet been able to prove it. Therefore, Monsters does not exist."

6.2. Definition

6.2.1. 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."

7. 9. Appeal to pity

7.1. Example

7.1.1. "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!"

7.2. Definition

7.2.1. The appeal to pity takes place when an arguer tries to get people to accept a conclusion by making them feel sorry for someone.

8. 8. Ad hominem and tu quoque

8.1. Example

8.1.1. "Andrea Dworkin has written several books arguing that pornography harms women. But Dworkin is an ugly, bitter person, so you shouldn't listen to her."

8.2. Definition

8.2.1. Like the appeal to authority and ad populum fallacies, the ad hominem ("against the person") and tu quoque ("you, too!") fallacies focus our attention on people rather than on arguments or evidence.

9. 6. Appeal to authority

9.1. Example

9.1.1. "We should abolish the death penalty. Many respected people, such as actor Guy Handsome, have publicly stated their opposition to it."

9.2. Definition

9.2.1. Often we add strength to our arguments by referring to respected sources or authorities and explaining their positions on the issues we're discussing. If, however, we try to get readers to agree with us simply by impressing them with a famous name or by appealing to a supposed authority who really isn't much of an expert, we commit the fallacy of appeal to authority.

10. 5. Weak analogy

10.1. Example

10.1.1. "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."

10.2. Definition

10.2.1. Many arguments rely on an analogy between two or more objects, ideas, or situations.

11. 4. Slippery slope

11.1. Example

11.1.1. "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."

11.2. Definition

11.2.1. 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.

12. 3. Post hoc (also called false cause)

12.1. Example

12.1.1. "President Jones raised taxes, and then the rate of violent crime went up. Jones is responsible for the rise in crime."

12.2. DefinitiAssuming that because B comes after A, A caused B.on

13. 2. Missing the point

13.1. Example

13.1.1. "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."

13.2. Definition

13.2.1. The premises of an argument do support a particular conclusion—but not the conclusion that the arguer actually draws.

14. 1. Hasty generalization

14.1. Definition

14.1.1. Definition: Making assumptions about a whole group or range of cases based on a sample that is inadequate

14.2. Example

14.2.1. "My roommate said her philosophy class was hard, and the one I'm in is hard, too. All philosophy classes must be hard!"

15. Finding Fallacies in Your writtings

15.1. • Pretend you disagree with the conclusion you're defending.

15.2. •List your main points; under each one, list the evidence you have for it.

15.3. •Learn which types of fallacies you're especially prone to, and be careful to check for them in your work.

15.4. •Be aware that broad claims need more proof than narrow ones. Claims that use sweeping words like "all," "no," "none," "every," "always," "never," "no one," and "everyone" are sometimes appropriate

15.5. • Double check your characterizations of others, especially your opponents, to be sure they are accurate and fair.

16. False Fallacies

16.1. What are fallacies?

16.1.1. Commonality

16.1.1.1. Fallacious arguments are very, very common and can be quite persuasive, at least to the casual reader or listener. You can find dozens of examples of fallacious reasoning in newspapers, advertisements, and other sources. Second, it is sometimes hard to evaluate whether an argument is fallacious.

16.1.2. Strength of the argument

16.1.2.1. An argument might be very weak, somewhat weak, somewhat strong, or very strong. An argument that has several stages or parts might have some strong sections and some weak ones. The goal of this handout, then, is not to teach you how to label arguments as fallacious or fallacy-free, but to help you look critically at your own arguments and move them away from the "weak" and toward the "strong" end of the continuum.

16.2. Arguments that provisions high altitude of fallacies

16.2.1. abortion, gun control, the death penalty, gay marriage, euthanasia, and pornography. The purpose of this handout, though, is not to argue for any particular position on any of these issues; rather, it is to illustrate weak reasoning, which can happen in pretty much any kind of argument!