Work in groups of four and try to detect problems in the following examples. Then match the problems with the stated fallacies.

A fallacy is, very generally, an error in reasoning. This differs from a factual error, which is simply being wrong about the facts. To be more specific, a fallacy is an“argument” in which the premises given for the conclusion do not provide the needed degree of support.

1) Detect problems from the following arguments.

Example I:

Ferris: So, who are you going to vote for?

Libard: Well, I was thinking about voting for Jane, since she is a woman and there has never been a woman chair here. But, I think that Steve will do an excellent job. He has a lot of clout in the university and he is a decent person.

Ferris: You know, Wayne and Bill are supporting him. They really like the idea of having Steve as the new chair. I never thought I’d see you and those two pigs on the same side.

Libard: Well, maybe it is time that we have a woman as chair.

Example II:

Jane: I’ve been thinking about getting a computer. I’m really tired of having to wait in the library to write my papers.

Bill: What sort of computer do you want to get?

Jane: Well, it has to be easy to use, have a low price and have decent processing power. I’ve been thinking about getting a Kiwi Fruit 2200. I read in that consumer magazine that they have been found to be very reliable in six independent industry studies.

Bill: I wouldn’t get the Kiwi Fruit. A friend of mine bought one a month ago to finish his master’s thesis. He was halfway through it when smoke started pouring out of the CPU. He didn’t get his thesis done on time and he lost his financial aid. Now he’s working over at the Gut Boy Burger Warehouse.

Jane: I guess I won’t go with the Kiwi!

Example III:

Bill: Jill and I both support having prayer in public schools.

Jill: Hey, I never said that!

Bill: You’re not an atheist. Are you, Jill?

Example IV:

Bill: I think that some people have psychic powers.

Jill: What is your proof?

Bill: No one has been able to prove that people do not have psychic powers.

Example V:

Joe: Man, I’d never want to go to New York. It is all concrete and pollution.

Sam: Not all of it.

Joe: Sure it is. Everytime I watch the news they are always showing concrete skyscrapers, and lots of pollution.

Sam: Sure, that is what the news shows, but a lot of New York is farmlands and forest. It is not all New York City, it just receives most of the attention.

2) Match the fallicies above with their names.

① False Dilemma is a fallacy in which a person uses the following pattern of“reasoning”:

Either claim X is true or claim Y is true (when X and Y could both be false).

Claim Y is false.

Therefore claim X is true.

② Spotlight fallacy is committed when a person uncritically assumes that all members or cases of a certain class or type are like those that receive the most attention or coverage in the media. This line of “reasoning” has the following form:

Xs with quality Q receive a great deal of attention or coverage in the media.

Therefore all Xs have quality Q.

③ Misleading Vividness is a fallacy in which a very small number of particularly dramatic events are taken to outweigh a significant amount of statistical evidence. This sort of “reasoning” has the following form:

Dramatic or vivid event X occurs (and is not in accord with the majority of the statistical evidence) .

Therefore events of type X are likely to occur.

④ B urden of Proof is a fallacy in which the burden of proof is placed on the wrong side. Another version occurs when a lack of evidence for side A is taken to be evidence for side B in cases in which the burden of proof actually rests on side B. A common name for this is an Appeal to Ignorance. This sort of reasoning typically has the following form:

Claim X is presented by side A and the burden of proof actually rests on side B.

Side B claims that X is false because there is no proof for X.

⑤ Guilt by Association is a fallacy in which a person rejects a claim simply because it is pointed out that people she dislikes accept the claim. This sort of “reasoning” has the following form:

It is pointed out that person A does not like accept claim P.

Therefore P is false.

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