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LogicalFallacies
LogicalFallacies
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A Logical Fallacy Is
Erroneous reasoning, improper expression, or
flawed argument due to irrelevant or inadequate
evidence
An error in reasoning that is compelling
nonetheless.
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Types Of Logical Fallacies
Hasty Generalization
Post Hoc
Non Seqitr Slippery Slope
Arging in a !ircle
Poplar Appeal
S"stitting t#ePerson
A$ Ho%ine% False Analogy
&e$ Herring
Stra' (an
And thats just to name a few
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Hasty Generaliation!efinition"
!rawing a conclusion #ased on insufficient evidence
Example" I was attacked by a Siamese cat; therefore, all cats are
dangerous.
Avoidance"!o not $ust rely on the opinions or experiences of $ust a
few people, and do not use one piece of evidence to reach
a sweeping conclusion.
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%ost Hoc &False 'ause(
!efinition"Arguing that #ecause ) came after A, A must have
caused )
Example" He raised taxes, and then the rate of violent crime went
up. He is responsible for the rise in crime.
Avoidance"Explain how A caused )* don+t $ust say that A came first
and ) came later
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-on equitur
!efinition"Logic that $ust does not follow or is not in sequence*assuming a causal relationship exists #etween two thingswhen one does not exist
Example" Sixty-two percent of men who drive udis have mustaches;
therefore, growing a mustache makes a man more likely todrive an udi.
Avoidance"
)e sure conclusions actually ma/e sense in relation to thefirst point made.
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Arguing in a 'ircle
!efinition"
upporting an argument with a part of the argument itself
Examples"
Hockey is the best sport because it is superior to all other
sports.
Avoidance"
!on+t use a point to prove a very similar point.
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%opular Appeal &)andwagon(
!efinition"!rawing a conclusion #ased on what everyone else is
doing
Example" #heating is totally okay; at least $%& of students do it.
Avoidance"
!on+t #elieve a conclusion $ust #ecause everyone else
#elieves it or all the cool people #elieve it, etc.
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u#stituting the %erson
!efinition"
-ame0dropping to prove an argument* using a
person1name in place of actual proof
Example"
'iger (oods uses )ike* I should use )ike+
prah says that everyone should watch r. hil, so I
watch r. hil.
Avoidance"
!on+t relying on a point $ust #ecause of who said it.
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Ad Hominem
&hooting the 2essenger(!efinition"
Arguing against the messenger rather than theconcept. %erson A ma/es 'laim ). 3here issomething o#$ectiona#le a#out %erson A* therefore,
'laim ) is false.
Example" /red likes the knitting team; I think /red might be cra0y
so there is no way the knitting team is a good activity forour school to have.
Avoidance"
Argue the point, not the source. 11
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False Analogy!efinition"
Arguing that something is li/e another thing when itreally is not
Example" 1uns are like hammers2they!re both tools with metalparts that could be used to kill someone. nd yet itwould be ridiculous to restrict the purchase of hammers2so restrictions on purchasing guns are e3uallyridiculous.
Avoidance"
4nly compare things with relevant properties.
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5ed Herring
!efinition"Going off on a tangent, raising a side issue that
distracts from what6s really at sta/e
Example" 'here is great merit in making re3uirements stricter for
graduate students. I recommend that you support it, too.
fter all, we are in a budget crisis, and we do not want
our salaries affected.
Avoidance"
tic/ to the topic.
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traw 2an
!efinition"Attac/ing a wea/ened or misconstrued form of theopponents+ argument
Example" 'he administration wants to block every website andpunish everyone who uses their laptop to its full potentialespecially if a student uses the laptop during the schoolday.
Avoidance"
tate opponents+ arguments as accurately as possi#le.Aim to attac/ the #est version of their argument.
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