Download
1 / 19
E N D
There are many ways in which reasoning can go wrong; that is, there are many kinds of mistakes in argument. It is customary to reserve the term “fallacy” for arguments that, although incorrect, are psychologically persuasive. Some arguments are so obviously incorrect as to persuade and deceive no one. But fallacies are dangerous because most of us are, at one time or another, fooled by some of them. A fallacy is often defined as a type of argument that may seem to be correct, but that proves, on examination, not to be so.
Since an artillery shell landed on this spot, we should use it as a foxhole; chances are that no shell will land there again. • Gambler’s fallacy.
My barber told me that Einstein’s theory of relativity is a lot of hogwash. I guess Einstein wasn’t as smart as everybody thinks he was. • Appeal to inappropriate authority.
Professor Snodblatt has argued against the theory of evolution. But Snodblatt is a pompous, egoistical windbag, and a card-carrying member of the Communist Biker’s Association. I absolutely refuse to listen to him. • Personal attack (ad hominem)
Senator Biddle has argued that we should outlaw violent pornography. Obviously, the Senator favors complete governmental censorship of books, magazines and films. Frankly, I’m shocked that such a view should be expressed on the floor of the United States Senate. It runs counter to everything this great nation stands for. No senator should listen seriously to such an outrageous proposal. • Straw man fallacy – the logical pattern of the straw man arguments is this: • 1. X’s view is false or unjustified [but where X’s view has been unfairly characterized or misrepresented]. • 2. Therefore, X’s view should be rejected.
Secretary to boss: I deserve a raise in salary for the coming year. After all, you know how friendly I am with your wife, and I’m sure you wouldn’t want her to find out what’s been going on between you and that sexpot client of yours. • Appeal to force – It is a psychological threat. The appeal to force fallacy usually accomplishes its purpose by psychologically impeding the reader or listener from acknowledging a missing premise that, if acknowledged, would be seen to be false or at least questionable. This example can be interpreted as concealing the following false premise: • If I succeed in threatening you, then I deserve a raise in salary.
Doctor: You should quit smoking. Patient: Look who’s talking! I’ll quit when you do, Dr. Smokestack! • Ad hominem (Tu Quoque) – The logical pattern of these arguments is this: • X fails to follow his or her own advice. • Therefore, X’s claim or argument should be rejected. But this reasoning is clearly wrong. Arguments are not good or bad because of who offers them but because of their own intrinsic strengths or weaknesses. You cannot refute a person’s arguments simply by pointing out that he or she fails to practice what he or she preaches.
Yes, Jill argues for deconstruction. But her mind is so open her brains are falling out. You can safely ignore whatever she has to say. • Personal attack (ad hominem). Note: No argument against deconstruction is given.
Innocent first step Disaster • Once you start prohibiting evidence that is illegally gathered, than other search and seizure laws will be passes, and soon all criminals will get off on technicalities and the guilty will be protected while the innocent are assaulted on our city streets. • Slippery slope – chain reaction not likely to occur.
The slippery slope fallacy can involve various kinds of causality. For example, someone might argue that removing a single brick from a building would set off a chain reaction leading to the destruction of the building, or that chopping down a tree would set off a cascade of falling trees leading to the destruction of the forest. These arguments depend on pure physical causality. On the other hand, someone might argue that starting a rumor about the health of the economy would set off a chain reaction leading to the collapse of the stock market. Such an argument would depend on the kind of causality found in interpersonal communications.
Deciding whether a slippery slope fallacy has been committed can be difficult when there is uncertainty whether the alleged chain reaction will or will not occur. But many slippery slopes rest on a mere emotional conviction on the part of the arguer that a certain action or policy is bad, and the arguer attempts to trump up support for his or her position by citing all sorts of dire consequences that will result if the action is taken or the policy followed.
After only one year the alternator went out in Mr. O’Grady’s Chevrolet. Mrs. Dodson’s Oldsmobile developed a transmission problem after six months. The obvious conclusion is that cars made by General Motors are just a pile of junk these days. • Hasty Generalization
I am entitled to say whatever I choose, because I have a right to say whatever I please. • Begging the question
Of course I believe in Martians, since there's no evidence that they don't exist. • Argument from ignorance
All of the really cool, intelligent, sophisticated students take critical thinking. Therefore, you should, too. • Appeal to the masses
Tell me, how long have you been embezzling money from the firm? • Complex question • Apparent single question is really two questions rolled into one. • Question 1: Have you been embezzling money from the firm? • If so, how long have you been engaging in this practice?
Aztec high priest: Every spring we sacrifice a virgin to the sun god, and every spring the life-giving rains come. Therefore, sacrificing a virgin to the sun god causes the life-giving rains to come. • False cause
Do most Americans still believe in God? To find out, we asked over 10, 000 scientists at colleges and universities throughout America. Less than 40 percent said they believed in God. The conclusion is obvious: Most Americans no longer believe in God. • Hasty Generalization - because other surveys have indicate that scientists tend do be far more skeptical of religious beliefs than the average American.
I had better eat my Wheaties. Michael Jordan says that it’s the breakfast of champions. • Inappropriate appeal to authority.
