Logical Fallacy Types

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Fallacy Types
Name Calling—A personal attack is committed when a person substitutes abusive
remarks for evidence when attacking another person's claim or claims. This line of
"reasoning" is fallacious because the attack is directed at the person making the claim and
not the claim itself.
"That claim cannot be true. Dave believes it, and we know how morally repulsive he is."
Band Wagoning—The Bandwagon is a fallacy in which a threat of rejection by one's
peers (or peer pressure) is substituted for evidence in an "argument." This line of
"reasoning" has the following form:
1. Person P is pressured by his/her peers or threatened with rejection.
2. Therefore person P's claim X is false.
This line of "reasoning" is fallacious because peer pressure and threat of rejection do not
constitute evidence for rejecting a claim. This is especially clear in the following
example:
Joe: "Bill, I know you think that 1+1=2. But we don't accept that sort of thing in our
group. "
Bill: "I was just joking. Of course I don't believe that."
It is clear that the pressure from Bill's group has no bearing on the truth of the claim that
1+1=2.
Non-Sequitur—(Latin for "it does not follow"), in formal logic, is an argument in which
its conclusion does not follow from its premises.
The term is often used in everyday speech and reasoning to describe a statement in which
premise and conclusion are totally unrelated but which is used as if they were. An
example might be: "If I buy this cell phone, all people will love me." However, there is
no direct relation between buying a cell phone and the love of all people. This kind of
reasoning is often used in advertising to trigger an emotional purchase.
Card Stacking—Card stacking is a propaganda technique that seeks to manipulate
audience perception of an issue by emphasizing one side and repressing another.
Following are some examples of the technique:
* Creating media events that emphasize a certain view,
* using one-sided testimonials, and
* ensuring that critics are not heard.
The technique is commonly used in persuasive speeches by political candidates to
discredit their opponents and to make themselves seem more worthy.
Begging the Question—The fallacy of petitio principii, or "begging the question," is
committed "when a proposition which requires proof is assumed without proof." More
specifically, petitio principii refers to arguing for a conclusion that has already been
assumed in the premise, in effect "begging" the listener to accept the "question"
(proposition) before the labor of logic is undertaken.
"If such actions were not illegal, then they would not be prohibited by the law."
Propaganda— is a form of communication that is aimed at influencing the attitude of a
community toward some cause or position so as to benefit oneself.
Post Hoc Ergo Propter Hoc—Post hoc ergo propter hoc, Latin for "after this, therefore
because of this," is a logical fallacy (of the questionable cause variety) that states, "Since
that event followed this one, that event must have been caused by this one."
The form of the post hoc fallacy can be expressed as follows:
* A occurred, then B occurred.
* Therefore, A caused B.
When B is undesirable, this pattern is often extended in reverse: Avoiding A will prevent
B.
The picture on Jim's old TV set goes out of focus. Jim goes over and strikes the TV
soundly on the side and the picture goes back into focus. Jim tells his friend that hitting
the TV fixed it.
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