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OG CR 48

Expert replies
by eccentric » Mon Sep 22, 2008 8:50 pm
A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The researcher
concluded from this experiment that the immune system protects against mental illness as well as against physical disease.
The researcher’s conclusion depends on which of the following assumptions?
A. High immune-system activity protects against mental illness better than normal immune-system activity
does.
B. Mental illness is similar to physical disease in its effects on body systems.
C. People with high immune-system activity cannot develop mental illness.
D. Mental illness does not cause people’s immune-system activity to decrease.
E. Psychological treatment of mental illness is not as effective as is medical treatment.

By POE A, C and B & E are together irrelevant, However D does not look convincing either...!!!
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Source: — Critical Reasoning |

by raunekk » Mon Sep 22, 2008 10:34 pm
imo:D

low levels of immune-system activity =>>>lower score on tests of mental health

there is a loop-hole ova here...
wat if the cause n the effect is opposite.

we have to remove this possibility.

i.e
Mental illness ==>>decrease in people’s immune-system activity

D does the same.
D. Mental illness does not cause people’s immune-system activity to decrease

It's an example of Defender Assumption
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by banker1 » Tue Sep 23, 2008 1:40 pm
What is the OA?

I agree (A), (C), and (E) are out of scope. (B) is tough but also out of scope since it talks about effects on body systems, not the immune system.

(D) is the only answer left however I'm struggling with raunekk's explanation.
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by stop@800 » Tue Sep 23, 2008 2:11 pm
OA has to be D.

In case of cause and effect CRs [where a leads to b]
we have an open assumption point that b caused a.
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by nervesofsteel » Wed Sep 24, 2008 12:11 am
D it should be

as A causes B is only true If we assume B doesn't cause A

Ie. Low mental activity causes low mental health

But if it can be proven that low mental health was not the cause of low mental illness then it can be proved that

Low mental activity ----> low mental health
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by umaa » Mon Feb 02, 2009 7:26 am
The researcher concluded from this experiment that the immune system protects against mental illness as well as against physical disease.

This is the conclusion. In assumption questions, answer is an evidence. it supports the conclusion.

Physical decease is not mentioned in first premise. But its there in the conclusion. So, obviously the assumption answer should have something about to physical decease.

I see nothing in the answer choices relevant to us. B has very little relevancy when comparing others. So, I chose B.

Am I missing something guys? I don't know why D is correct. I'm not convinced with the above explanations.
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by Brad.C » Fri May 13, 2016 2:24 pm
I think D should be the answer
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