PrepTest 132, Section 4, Question 13
Many symptoms of mental illnesses are affected by(54 more words not shown)
The reasoning above is most(8 more words not shown)
- Adoes not say(8 more words not shown)
- Bneglects the possibility(17 more words not shown)
- Cfails to consider(14 more words not shown)
- Dpresumes, without providing(15 more words not shown)
- Epresumes, without providing(10 more words not shown)
Reading the argument
What if something besides brain chemistry explains the difference?
The passage says organic factors affect many symptoms. It doesn't say they are the only influences on those symptoms. So when people with mental illnesses show different patterns of symptoms in different countries, we shouldn't immediately conclude that the organic factors must differ.
Imagine similar organic conditions in two countries, but different social environments that affect how people's symptoms show up. The observed symptoms could differ even though the organic factors were distributed similarly. We don't have to establish that this is what happens. It's a possible alternative the argument hasn't ruled out.
What we’re looking for
Keep the comparison precise: we're discussing symptoms among people with mental illnesses, not proving that one country has more mental illness overall. For the flaw, I'd look for another influence on those symptoms that could explain the variation.
Working the answers
- A
The number of illnesses isn't the missing connection. Whether the discussion covers a few illnesses or many, we would still need a reason to attribute the symptom differences to organic factors rather than some other influence. Giving a count wouldn't fix that inference.
- B
This may look like another cause, but follow its path. Different nutrition leads to different deficiencies in brain compounds. That would help explain how organic factors could differ across cultures, which fits the author's conclusion. It doesn't show how symptoms could vary while the organic factors remained similar.
- CCorrect
Culture could affect how an illness appears in symptoms. If that influence differs across countries, it could explain the symptom variation without establishing a corresponding difference in organic factors. This supplies the alternative explanation the argument overlooks.
- D
The argument doesn't say that every change in brain chemistry changes a person's mental condition. It starts with the more limited claim that many symptoms are affected by organic factors. The problem lies in attributing the observed variation to those factors, not in an explicit rule that every chemical change must have a mental effect.
- E
This is a broad claim about all mental phenomena and all physical phenomena. The argument doesn't need that sweeping view of the mind to make its mistake about these particular symptoms. It could allow some mental phenomena to have nonphysical explanations and still wrongly attribute this variation to organic factors. C targets the specific missed possibility directly.
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