QUESTION TEXT: Many symptoms of mental illnesses…
QUESTION TYPE: Flawed Reasoning
CONCLUSION: Organic factors aren’t evenly distributed.
REASONING: Mental illness symptoms vary around the world. Organic factors cause mental illness.
ANALYSIS: I couldn’t prephrase this one. I just looked through the answers quickly, and eliminated those that didn’t seem correct. I then returned to the answer that remained (C). On flaw questions, you’re looking for two things:
- The answer actually happened. Almost all flaw answer choices don’t occur in the stimulus.
- The answer is actually a flaw. For example, answer A may have happened, but it’s not an error.
As for the stimulus itself, I don’t have much commentary. The main thing I took from it is that mental illnesses vary around the world, and that the author thinks that this means organic factors vary.
___________
- This isn’t a flaw. From context, the author appears to be talking about all mental illnesses.
- The stimulus didn’t talk about nutrient deficiencies! This answer used that word because you’ve probably only heard deficiency refer to food. They know you well and they trapped you! “Deficiency” can refer to many things. The stimulus was about the brain being short of certain compounds. Not necessarily due to diet.
- CORRECT. This is a flaw. Cultures have many differences around the world. This can change how symptoms appear. In that case, the same organic compounds might be deficient around the world. But how people react to deficiencies would change due to culture.
- The argument didn’t do this! An answer can’t be a flaw unless it happens.
Example of flaw: Well, his brain chemistry changed in a really, really insignificant way, so obviously his mental condition will change. - The argument didn’t say this. Whether or not this is a flaw, it didn’t happen in the argument.
Recap: The question begins with “Many symptoms of mental illnesses”. It is a Flawed Reasoning question. To practice more Flawed Reasoning questions, have a look at the LSAT Questions by Type page.
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Bruce says
Graeme,
You say:
“On flaw questions, you’re looking for two things:
1.) The answer actually happened. Almost all flaw answer choices don’t occur in the stimulus.
2.) The answer is actually a flaw. For example, answer A may have happened, but it’s not an error. ”
What do you mean?
For flaw questions, I usually try to guess the flaw, or eliminate the questions that are wrong.
TutorLucas (LSAT Hacks) says
Hi Bruce,
Yes your approach of pre-phrasing (guessing) the flaw can be quite helpful. What Graeme is getting at is that the wrong answers are wrong for either 1 of 2 reasons. Either the flaw didn’t happen or it’s not a flaw. When eliminating answer choices it’s helpful to look for these two possibilities – even asking yourself as you read the choices, did this happen? is this a flaw? For instance, answer choice A is not a flaw and answers B,D, and E didn’t happen.
Hope this helps!
-Reply from LSAT Tutor, Morgan Barrett
MemberLSATmaniac2.0 says
Graeme,
I actually had a lot of trouble choosing between B and C. When I read your characterization of B, that made it a hundred times simpler to throw out, but I threw it out because of its overly general nature.
The stimulus says that “organic compounds” CAN affect symptoms. It never says it directly causes them. It could mean it exaggerates the symptoms. Also, “deficiencies in the brain” is only a single example of these “organic factors”. E.g. “organic factors SUCH AS a deficiency in a compound in the brain”. Lastly, as you say, there’s no telling whether or not eating/nutrition affects these SPECIFIC compounds. It could affect only 1 or 2 compounds that have to do with alertness, or sleepiness, rather than symptoms of mental diseases. Or nutrition could affect no compounds at all.
Even if nutrition did have some bearing on the symptoms, the deficiencies are only one part of the “organic factors” that the conclusion claims not to be evenly distributed.
TutorLucas (LSAT Hacks) says
Thanks for your thoughts on this question! Your reasoning for (B) being incorrect is spot-on.
Wendy says
Hi Graeme.
Thanks for your LSAT solutions – your explanations are really excellent and a wonderful resource!
I totally agree with most of your explanation here, but had a slightly different interpretation of (D). It seemed to me that (D) IS in the stimulus – that it’s actually kind of a necessary assumption for the stimulus conclusion to hold. But (D) is wrong because it’s too broad.
To recap—
Premises:
1. Symptoms of mental illnesses are affected by organic factors such as a deficiency in a compound in the brain.
2. The incidence of such symptoms (of mental illness) vary across different countries.
Conclusion: The organic factors affecting symptoms of mental illnesses are not evenly distributed globally.
In this case, for the author to claim that the variation in SYMPTOMS indicates a variation in ORGANIC FACTORS – it seems to be a necessary assumption that variation in organic factors (which effect mental illness symptoms) ACTUALLY changes the display of those symptoms. And on the corollary, that the changes in symptoms displayed is indeed reflective (“manifesting”) of changes in organic factors.
I.e. The conclusion claims that variation in mental illness symptoms are INDICATIVE OF (“this variation establishes..”) variation in organic factors. For symptoms and organic factors to be indicative of each other on the basis of observable incidence, they must in some sense be necessarily physically manifesting of each other.
That’s why I (erroneously) chose (D) anyway. Under this interpretation, (D) is wrong because it is too broad/kind of a “shell” answer:
– “any change in brain chemistry” (much broader than) > “organic factors such as a deficiency” in brain compound
– change in “mental condition” (broader than) > “symptoms in mental illnesses”
I’d love to hear your thoughts – about there being a necessary assumption in the stimulus regarding the link between changes in organic factors and the physical manifestation (symptoms) of those changes. (Of course D is incorrect, but here, I think (D) is incorrect for a slightly trickier reason than simply not being in the stimulus).
(Apologies for being long-winded. And kudos to your super-succinct explanations – It’s HARD writing non-long-winded-but-thorough explanations! Thanks again!)
FounderGraeme Blake says
When you say “too broad”, that’s what I meant by saying the stimulus didn’t say D. The stimulus didn’t say that ALL organic changes cause symptoms, which is what D says.
D is actually an insane statement that no one would believe. You have to take answer choices literally on the LSAT. And in most cases on a flaw question, if an answer is insane, then it wasn’t in the argument.
I think there is a necessary assumption: the author assumes that if there is a change in symptoms, then this must have been due to organic factors.
I’m not sure where you’re getting display of symptoms except from C. D doesn’t mention that. D is talking about how organic factors change the brain itself, but not about how those symptoms are presented to the outside world.
>>change in “mental condition” (broader than) > “symptoms in mental illnesses”
Yes, if you mean that there could be a change in mental condition without it showing up as a symptom.
I’ll confess that I’m not 100% sure what your theory is and how D relates. Hopefully I covered it.
Wendy says
Thanks – very helpful as always. What I was trying to point to is simply the necessary relation between the physical symptoms and the mental illness.
Something like it has come up as an assumption in other LR assumption questions. ‘It’ being an assumption reasserting the link between a thought/belief/impression ( ie. She thought X was true) and the actuality of X being true.
Or, maybe more concretely. E.g. To conclude that he is sick because he is coughing, you would necessarily have to believe that sickness manifests itself physically as coughing.
Don’t want to complicate things for anyone else / so its just my personal thought process here. Stick with Graemes explanation :)
FounderGraeme Blake says
Oh, I see. The first sentence of the stimulus covers this. It says “Many symptoms of mental illnesses….”
That means the symptoms discusses are actually the symptoms of the mental illnesses in question. That sentence explicitly covers the possibility you’re bringing up.