Definitions of the informal fallacies are found in the Glossary. Your identification requires an explanation of why the example is an example of the fallacy you say it is (see Chris Earls' explanation for his false dichotomy example in the fallacy entry).

1. Either tomorrow is Tuesday or it is not.

2. We can't find an elephant in this classroom; thus there is no elephant here.

3. In the absence of compelling evidence to the contrary, physcians should not require women in their forties to have an annual mammogram.

4. Either you do well in logic or you don't ever graduate. It's your choice.

5. Doctors recommend annual check ups because of their value in the early detection of disease. But doctors are not to be trusted. They are all greedy, blood-sucking quacks. You should stay away from doctors and their check ups.

6. God exists. It says so in the Bible, and the Bible is the Word of God.

7. I should be allowed to own a gun. The Bill of Rights says that "A well-regulated militia being necessary to the security of a free State, the right of the people to keep and bear arms shall not be infringed." [But this applies to the people as a whole, to the state--not to individuals.] Well, what's true for the state is true for me. I am a citizen, after all.

8. "I am all for women having equal rights," said Bullfight Association President Paco Camino. "But women shouldn't fight bulls because a bullfighter is and should be a man."

9. A light bulb uses less energy than the television. Therefore, it costs more to watch television than to leave the lights on.

10. We have found no evidence to support the claim that he acted in self-defense.

11. George will certainly know something about prison routine at the state prison. He's an ex-con who served eight years in the state prison for armed robbery.

12. God must exist; otherwise life would be unbearable.

13. I am convinced that Vitamin C really works. Every member of my family used to have at least one cold each winter. Last fall each of us started taking 1,000 milligrams of Vitamin C a day, and there hasn't been even a sniffle at our house since then.

14. Women are so sentimental! My mother and sisters always cry at movies.

15. I think his daughter's marriage must have worried him dreadfully. She is his only child, you know. He never talked about her getting married, but I noticed that his hair began to turn white soon after the wedding.

16. It is predicted that the consumer price index will rise again next month. Consequently, you can expect to pay more for gas and groceries next month.

17. A mob is no worse than the individuals in it.*

18. Radical feminists seek to ban pornography. But if we censored anything that offends someone, nobody would be able to say anything.

19. Fallacies are difficult to identify because they are so tough to pick out.

20. Ms. De Mark has provided evidence that children who watch more than two hours of television daily do not perform as well in school as those who watch no television. But who would want to give up television? It's a source of news and weather reports. It provides large varieties of entertainment for little more than the cost of the set. Surely her conclusions are flawed.*

21. The clerks at Mason's Department Store are incompetent. They got two of my orders mixed up during the last Christmas rush season. It took me forever to get things straightened out.

22. If you miss one class, then you will miss another. It is just like eating potato chips. You can't just eat one. One miss is never enough. Before long you will miss another and another and another. Next thing you know you will be out of school. You should never miss a class for any reason.

23. Mike is a great logic teacher. I see him on the bus sometimes. That is good enough for me. Riding the bus is the logical thing to do.

24. The flow of electricity through a wire is similar to the flow of water through a pipe. When water runs downhill through a pipe, the pressure at the bottom of the hill is greater than it is at the top. Thus, when electricity flows downhill through a wire, the voltage should be greater at the bottom of the hill than at the top.

25. Mike can't be right about this fallacy. He is so ugly that he can't know what he is talking about.

26. We have a duty to do what is right. We have a right to speak out in defense of the innocent. Therefore, we have a duty to speak out in defense of the innocent.

27. Consumer's Digest reports that GE light bulbs last longer than Sylvania bulbs. But do you realize that GE builds nuclear power plants? We now face a tremendous problem in this country with the safe disposal of nuclear waste. Given GE's role in all this, Consumer's Digest must be wrong.

28. Immediate steps should be taken to outlaw pornogrphy once and for all. The continued manufacture and sale of pornographic material will almost certainly lead to an increase in sex-related crimes such as rape and incest. This in turn will gradually erode the moral fabric of society and result in crimes of all sorts. Eventually a complete disintegration of law and order will occur, leading in the end to the total collapse of civilization.

29. Murder is morally wrong. This being the case, it follows that abortion is morally wrong.

30. Crumbs have virtually no calories. So if you break your favorite cookie up into crumbs and eat the crumbs, you ingest virtually no calories.*

31. My car's engine doesn't run. So my car doesn't run.

32. Ms. McKay contends that terminally ill patients have a right to die with dignity. But murder, whether self-inflicted or other-assisted, is still murder. And murder is wrong!

33. Maggie has argued that the system of letter grades should be abolished. But such a position assumes that there are not genuine differences in the quality of work done by students, which is absurd. So the system of letter grades should not be abolished.*

34. Water puts out fire. Oxygen is a part of water. So oxygen puts out fire.*

35. Francesca claims that the government should not interfere with the personal lives of the governed. But this is just another version of the old saw that the government that governs least governs best, which implies that the best government doesn't govern at all. But if there were no government, there would be anarchy. Anarchy is untenable. So we obviously must reject Francesca's claim.*

36. Given the environmental problems we face, either we quit using fossil fuels or we reduce the world to ashes.

Note: Items marked with an asterisk are taken (or adapted) from Daniel E. Flage, Understanding Logic (Prentice-Hall, 1995).

Michael Eldridge, Department of Philosophy, UNC Charlotte (mleldrid@email.uncc.edu or 704/687-3318)

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