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. “I asked my doctor why my mouth was so dry, and he told me that it was because my
saliva glands are not producing enough saliva.”
What do you think of the doctor’s diagnosis? This is an example of the fallacy of begging the question,
or circularity. This fallacy occurs when the solution to a problem is a restatement of the problem, or
when the argument for a proposition is equivalent to the proposition. Diagnosis of mental disorders
is sometimes considered to beg the question. Consider the following exchange.
Question: Why is he so nervous and agitated?
Answer: He has Generalized Anxiety Disorder.
Question: What does that mean?
Answer: It means that he is constantly nervous and agitated.
As the questioner, you have no more knowledge at the end of the exchange than you did at the
beginning. You have just been given a label for what you already know. Some examples of this
fallacy seem ridiculous, but they occur frequently and are often generally accepted. Consider
gravity. We all know what it is, but does it really explain why objects are attracted to each other?
No, it simply labels the fact that they are.
· “He is an innocent man. He was tried before a jury of his peers and the prosecution was
unable to prove him guilty.”
Is the assumption of innocence justified? This is an example of the fallacy called appeal to ignorance.
This fallacy occurs when it is argued that because we cannot prove a proposition true, it must be
false; or if we cannot prove a proposition false, it must be true. As an example, think about this
statement: “There has never been any scandal about this candidate for President. Therefore, he
must be an honest, moral person.” Is that really true?
· “If you don’t pick up your clothes before you go to bed at night, pretty soon you’ll be knee
deep in dirty clothes.”
Is that the way it is? This is an example of the slippery slope fallacy; certain applications of it have
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CHAPTER 9: COGNITIVE PROCESSES
been called the domino theory. The argument is that if the first in a possible series of steps or events
occurs, the other steps or events are inevitable. Here is an example from a letter to the editor of a
metropolitan newspaper, in which the writer was responding to an article discussing the morality
of euthanasia in the case of a person with advanced multiple sclerosis. “If we allow this to happen,
where do we stop? Who would decide at what point someone should die? Do we give them poison
the moment they know they have multiple sclerosis or cancer, before they have any suffering?”
. “TV can’t be harmful for children because it occupies their attention for hours and keeps
them off the streets.”
Is this argument against the idea that TV can be harmful for children convincing? It is an example
of the fallacy called irrelevant reason. This fallacy occurs when the argument given to support a
proposition has little or no relevance to the original proposition. Let us look at one more example.
“Conservationists have suggested that we could conserve fuel by increasing the tax on gasoline.
But more taxes, whether they’re paid by the oil companies or passed on to the consumer at the
pump, will not produce one more barrel of oil.”
· “I don’t see how he can get elected. No one I know is going to vote for him.”
What’s wrong with this argument? This is the hasty generalization fallacy. It occurs when an
isolated or exceptional case is used as the basis for making a general conclusion. In statistical
terms, it is making a conclusion about a population based on information obtained from a sample
that is biased or too small to be representative. It is an error of inductive reasoning, going from the
particular to the general when it is not justified by the evidence.
. “If socialized medicine will result in better and lower-cost health care, shouldn’t the same
logic be applied to automobiles?