Errors in Reasoning
Fallacies
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A Fallacy is “any error in reasoning that makes an
argument fail to establish its conclusion.”
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There are two kinds of fallacies Formal and Informal
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This chapter focuses on informal fallacies.
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Informal fallacies have recognizable errors in
content
The Fallacies begin
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Appeal to ignorance – claiming something is true (or
false) just because we cannot prove it is false (or
true).
For example: “you cannot prove that God does not
exist. Therefore God does exist.” Or, “you cannot
prove the defendant is innocent, therefore he is
guilty.”
The Problem is that lack of evidence often does not
prove anything, although sometimes it does.
Appeal to false authority
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This fallacy claims that “so-and-so” says “X is true”
or “X is false” and rests the argument on “so-andso's” authority; but, in fact, “so-and-so” is not really
an expert on the matter they speak for.
For example: Jenny McCarthy and Jim Carey are
public proponents for the view that some vaccines
cause autism. But, of course, McCarthy and Carey
have absolutely no expertise in this area.
Appeal to Popular opinion
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This fallacy holds that because the majority of
people think something is true, it is, therefore, true.
This kind of thinking is often behind opinion polls
where we learn that, say, 57% of Americans think X
or y.
The problem is that the majority of people have
often believed in terrible things, like thinking
women should not be allowed to vote, or that slavery
was a good thing. Nothing is right just because most
people think it is so.
Appeal to tradition
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Quite similar to the appeal to popularity, but here the
argument is that “we have always done it this way,
so it is the right way to do things.”
This argument suffers from the same flaw, just
because something has always been done a certain
way, does not mean it is right.
For example: someone might claim that marriage
must be between “one man and one woman” simply
on the grounds that “it has always been so.” Nothing
follows from this
Against the Person
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This argument attacks a person's character rather
then their argument.
For example: “Rush Limbaugh says global warming
is not real. Limbaugh, however, is a big fat idiot! We
must conclude therefore that Rush is wrong about
Global warming.
There are some other versions of this fallacy: you
can attack someone's circumstances rather than their
argument, you can poison the well, or use what is
called the tu quoque (you too) fallacy.
Against the person in action
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You can't believe anyone who looks like this:
Emotion based fallacies
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Appeal to pity – takes an emotional response to an
unfortunate situation as a reason to believe or act in
a certain way
Appeal to Emotion – Believe that something is true
because it makes me feel good, or that it is false
because it makes me feel bad.
Appeal to Force – This fallacy basically says “do
this or something bad will happen to you!”
Irrelevant Conclusion
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This is an argument in which premises are given but
the conclusion really has nothing to do with them.
For example: If you vote you participate in
democracy. If you participate in democracy you
count as a citizen. Therefore, Democracy is better
than all other types of governments
The most common types of arguments given here
are the red herring and the straw man
Red Herring
http://www.youtube.com/watch?v=exdK7Lirngg
Straw Man
http://www.youtube.com/watch?v=v5vzCmURh7o
&feature=related
Loaded Question & Loaded Language
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Loaded language is language that creates bias before
a point is even made
For instance: “my opponent, that dishonest jerk over
there, wants to ....”
A loaded question is designed to trap the view into
answering against themselves
For instance: “have you stopped cheating on your
taxes yet?” Or “what were you doing there at that
time on that night?”
False Cause
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There are several versions of this fallacy. We will
focus, however, on one particular version: the socalled post hoc fallacy
The post hoc fallacy states that because one event
follows shortly after another event, the first event
caused the other. This is a fallacy because merely
preceding something in time does not make an event
the cause of another
For instance, suppose I come home from a trip and
my wife gets over a case of the flu: my coming
home did not cause her recovery
A few other fallacies
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Begging the question – assuming what you are
trying to prove
Hasty Generalization – making a conclusion about
an entire group based on a small selection of
samples. This is often a worry when opinion polls
are taken
False Dilemma- claiming that someone only has two
options when they actually have at least three.
Equivocation – using the same word but changing
the meaning of it, while, at the same time, acting as
if you did not do so.
Fallacies in our daily decisions
http://movies.netflix.com/WiMovie/Frontline_The_
Vaccine_War/70138090?trkid=2361637#height1
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