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 Jkjones3789
  • Posts: 89
  • Joined: Mar 12, 2014
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#17563
Hello, I got this flaw question wrong. Could you please tell me what the flaw in the question is and why the answer is C, and also why it isn't A? Thank You. I was also wondering if this question could've been answered by paralleling the degree of certainty in the conclusion. All the other answer choices have must, and E is different in structure than the stimulus. Will and must don't have the same strength logically right?
 Lucas Moreau
PowerScore Staff
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  • Joined: Dec 13, 2012
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#17575
Hello, Jkjones,

I can see where you had a difficulty. E is a Mistaken Reversal, whereas the flaw in the stimulus is a Mistaken Negation. Saying:

No!Public Access :arrow: Polluted
to
Public Access :arrow: No!Polluted

A is not a flawed answer choice - A contains no flaw at all. :0 A describes a relationship and its valid contrapositive, where the terms are both negated and reversed as they should be.

C is the correct answer choice because it has the same type of Mistaken Negation flaw as the stimulus does:

No!Prisoner Mixing :arrow: Violence Increase
to
Prisoner Mixing :arrow: No!Violence Increase

Hope that helps,
Lucas Moreau
 Jkjones3789
  • Posts: 89
  • Joined: Mar 12, 2014
|
#17576
For some strange reason when I am diagramming out the answer for D I am getting this

Solitary Confinement :arrow: Violence increase

No solitary confinement :arrow: no increase

I see that this is a mistaken negation but is it still paralled given that it has two negatives but the stimulus only had one? Sorry if thats a dumb question figured now is like my last chance to ask :oops: .. Thank you
 Emily Haney-Caron
PowerScore Staff
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|
#17588
Hi Jkjones,

Definitely not a dumb question! I'm glad you asked. For parallel flaw questions, you are trying to find the answer choice where the type of flawed reasoning is closest to that in the stimulus. The specifics of which terms are negative vs. positive, etc., are less important; most important is matching the flaw, in this case, a mistaken reversal. I could diagram the stimulus to have two negatives, as well:
public restricted :arrow: pollution
NO public restricted :arrow: no pollution

So, your diagramming wasn't wrong, but there are a couple of correct ways to do it, as long as you are consistent throughout. Does that help?
 Jkjones3789
  • Posts: 89
  • Joined: Mar 12, 2014
|
#17593
Thank you so much. I'm all clear now :-D
User avatar
 broth99
  • Posts: 18
  • Joined: Mar 03, 2021
|
#96924
Hi,

Quick question. if MR and MN are contrapositives of each other, then shouldn't B,C, and E all be possible answers since they are all MR. Therefore, if we just rephrase B,C, and E to their contrapositives, it would be a MN, just like flaw in the stimulus.

Thanks,
Barath
 Robert Carroll
PowerScore Staff
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|
#97237
Barath,

Mistaken Reversal and Mistaken Negation may involve the same mistake, but arguments using them differ in their logical structures. I've discussed this distinction elsewhere, which I'll link here: viewtopic.php?p=87775#p87775

Robert Carroll

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