More common fallacies! What you need to know… Chapter 7
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More common fallacies!
What you need to know…
Chapter 7
AD HOMINEM FALLACIES
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Argumentum ad hominem: themost common fallacy on earth.
Example:
“According to Al Gore, global warming isthe most serious threat facing us today.Folks, what a crock. Al Gore spends$20,000 each year on electricity in hisTennessee mansion!”
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The only crock here is thatargument! Why is it a fallacy?
Look at it logically:
Premise: All Gore spends $20,000each year on electricity.
Conclusion: Therefore global warmingis not the most serious threat facing ustoday.
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In case you still don’t see it:
Issue: Is global warming the mostserious threat?
Which of the following assertions isRELEVANT?
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GW will cause rising sea levels to swamp alleast coast cities by 2100.
GW will cause coral reefs to die within 30years.
CO2 levels have risen over 30% in the last 25years, due to GW.
According to a study published in Nature,current rates of warming will lead to extinctionfor 1 million species by 2050.
All Gore spends $20,000 a year onelectricity—NOT RELEVANT!
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ATTACK ad hominem
“What Al Gore says about air pollution isa joke! That clown will say anything toget attention!”
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CIRCUMSTANTIAL ad hominem
“What Al Gore says about air pollution ispure bull. Al Gore makes a fortune fromalternative energy investments. What doyou think he’d say?”
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INCONSISTENCY ad hominem
“Senator Clinton says we should get outof Iraq. What a bunch of garbagecoming from her! She voted for the war,don’t forget.”
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POISONING THE WELL
“Senator Clinton is going to give a talktonight on Iraq. Well, it’s just gonna bemore baloney. That gal will say anythingto get a vote.”
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GENETIC FALLACY
“Does God exist? Of course not. Thatidea originated with a bunch of ignorantpeople who knew nothing aboutscience.”
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GENETIC FALLACY:
Rejecting an idea as false because itcame from a defective source.
Rejecting some particular person’s ideaas false because there is somethingdefective about the person.
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Ad hominem:
GENETIC FALLACY:
“Does God exist? Of course not. Thatidea originated with a bunch of ignorantpeople who knew nothing about science.”
“John says God exists. What nonsense.He’s just saying that because he works fora church.”
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Circumstantial ad hominem:
New fallacy!
FALSE DILEMMA
Also known as Black/White; Either/Or;All/Nothing.
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FALSE DILEMMA
Example:
“Either we increase the number oftroops in Iraq or the terrorists will beattacking U.S. cities. Seems like asimple choice to me.”
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“PERFECTIONIST” version offalse dilemma
Example:
“It’s impossible to eliminate terrorismentirely. We should stop wastingmoney on it.”
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“LINE-DRAWING” version offalse dilemma
Example:
“ There shouldn’t be restrictions onviolence in the movies. After all, when isa movie ‘too violent’? You can’t draw aline.”
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Now two other famous fallacies:
STRAW MAN
SLIPPERY SLOPE
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STRAW MAN
Example:
“Twenty percent? You want to tip her20%???? Hey, maybe you want to giveher everything we make, but I franklythink that is ridiculous!”
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SLIPPERY SLOPE
Example:
“Twenty percent? You want to tip her20%? Hey, next thing you’ll want to tip25%! And then 30%! It will never end.”
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Two more famous twins:
BEGGING THE QUESTION
MISPLACING THE BURDEN OFPROOF
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MISPLACING THE BURDEN OFPROOF:
Example:
“Can I prove the Biblical flood reallyhappened? Hey, can you prove itdidn’t???”
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BEGGING THE QUESTION
Example:
“Can I prove the Biblical flood reallyhappened? Of course it happened! Whyelse would Noah build an ark???”
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What they all have in common:
They don’t demonstrate theirconclusion.
They don’t support their conclusion(they don’t make their conclusion morelikely).
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