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#36823
Complete Question Explanation

Parallel Reasoning. The correct answer choice is (E)

Based on the premise that Dr. Grippen’s and Dr. Heissmann’s theories predict mutually exclusive
outcomes, the author concludes that the planned experiment will confirm one theory at the expense of
the other.

The reasoning is flawed, because it ignores the possibility that the experiment might disprove both theories. There is no reason to presume that one of the theories must be confirmed. Since we are asked to
parallel the flaw, we must find a choice that similarly neglects the possibility of two negative evaluations.

Answer choice (A): This reasoning is fairly sound. If David and Jane often disagree, at least one of their
methods is probably flawed. This choice does not parallel the reasoning in the stimulus, because at least
one
in this case means either one or both.

Answer choice (B): The reasoning in this choice is bad, but only because it neglects the possibility that
both David and Jane agree on the description of the tree, but simply disagree over its name, which is not
a similar flaw.

Answer choice (C): This choice is wrong, because it ignores that even if David is one tree better, a
difference of one tree is really not enough to decide who is better at identifying trees. However, the two
flaws are not analogous, so this choice is wrong.

Answer choice (D): The reasoning in this choice is sound. Examining the whole forest would establish
whether David is correct to believe there are more beeches than elms in the forest, so this response
contains no logical flaw and is incorrect.

Answer choice (E): This is the correct answer choice. Both David and Jane could be wrong, so Maria
does not have to confirm either of these judgments, but the choice ignores that possibility. That is exactly
the flaw in the stimulus. In this case, David and Jane are the scientists, and Maria is the experiment.
 Nina
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#6094
I wasn't quite sure about the erroneous pattern of reasoning in the stimulus. Does the flaw lies in that it ignores the possibility that both theories can be wrong?

Thanks a lot!
 Steve Stein
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#6096
Based on the premise that Dr. Grippen’s and Dr. Heissmann’s theories predict mutually exclusive outcomes, the author concludes that the planned experiment will confi rm one theory at the expense of the other. The reasoning is fl awed, because it ignores the possibility that the experiment might disprove both
theories. There is no reason to presume that one of the theories must be confirmed.

I hope that's helpful! Let me know whether it's clear--thanks!

~Steve
 Nina
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#6099
yeah, it's clear now. Thanks Steve!
User avatar
 Ian888
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#95039
Hello,

Here's my issue. I understand why E is correct, but why can't D be correct? What if they count the tress in the forest and there's 50 beeches and 50 elms?

As I was writing this I see why now. Even if there's 50/50 then he's still either correct or incorrect about there being MORE beeches than elms. I hate this test. :(
 Robert Carroll
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#95095
Ian888,

I see you got it eventually! That's why you have to be careful, but good job getting it!

Robert Carroll

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