Q2 - The vomeronasal organ (VNO)

[weiyichen1986]

Hi, can anyone explain why A is the correct answer, i really did not get it? i pick C on this one though

Thanks

[shaynfernandez]

The core is this

Evidence: when researchers have been able to stimulate VNO cells the subjects reported subtle smell sensations.
Conclusion: then it seems that the VNO is a functioning sensory organ in most humans.

There is a few flaws that we can deduct from this argument.
1. There is a hint of implicit causality, stimulating the VNO being the cause and subtle smell sensations being the effect.
2. The author assumes that if a human has a detectable VNO then it is a functioning sensory organ. This is seen in the gap between "most humans" in the premise and "most humans" in the conclusion.
3. The author also assumes that "experiencing subtle smell sensations" is sufficient evidence for us to reach the conclusion that the VNO is a functioning sensory organ.

Answer choice A addresses the first flaw we spotted. It weakens the argument by questioning the reasoning between the evidence and the conclusion, which in this case is causality. It allows us to question the validity of the causal relationship by bringing up an alternative explanation. Maybe other cells were stimulated and that's what caused the effect of subtle smell and it wasn't the VNO.... If that's true then the author would have a difficult time explaining that VNO is a functioning sensory organ.

C) is a tempting choice because it "could" weaken an argument, but it just can't weaken "this" argument. This argument is what we stated earlier as the core, but C only brings us temptation because it is borrowing background information "animals" from our stimulus that is not in our core. Thus it is out scope for that reason. Also we are not concerned about chemicals or leading roles... A conclusion was made based on evidence that did not include either of these two things. The reasoning was flawed but not for the reasons C presents so it cannot weaken an argument it has no relevance to.

Let me know if that doesn't answer your question.

[gmatalongthewatchtower]

Tutors,

I have a question. I read this example in MLSAT book. Can you please explain where should I draw the line between "claim in premise" and "fact". I read the evidence again and again. How do I know whether " when researchers have been able to stimulate THE VNO cells the subjects reported subtle smell sensations." is a claim within Premise and not a fact?

The sentence has used "THE VNO", denoting that VNO was stimulated specifically. I see that the book talks about inadequate prenatal example. However, there we have an explicitly mentioned subject "Medical Researcher." Here we don't. Further, there are no "Conclusion" or "claim" markers such as "likely, possibly...etc".

Please help me

[ManhattanPrepLSAT1]

I read this example in MLSAT book. Can you please explain where should I draw the line between "claim in premise" and "fact".

Facts are simply statements made or claims. We can identify the conclusion with the language "it seems." Also, claims that represent predictions, recommendations, hypotheses, and decisions, while not always conclusions, tend to be so generally. This conclusion is a hypothesis.

And hypotheses are really common forms of conclusions in a very particular pattern of arguments all over the logical reasoning section.

Evidence: observed phenomenon (stimulate the VNO and smell occurs)
Conclusion: VNO is a sensory organ

Well, that might be the case, but there other possible explanations for why a smell was produced. Maybe during our attempt to stimulate the VNO, we also stimulated the sensory organ responsible for smell. To weaken an argument of the form we see, we simply provide an alternative explanation - as is accomplished in answer choice (A).

Further, there are no "Conclusion" or "claim" markers such as "likely, possibly...etc".

We definitely a conclusion markers in the form of the claim (a hypothesis) and the language cue "it seems." What we are not given is a language cue implying causation, even though that's really the issue being hypothesized. This is really common when the argument offers an explanation for something strange. We are much more likely to get language cues that imply causation when the argument establishes a correlation between two things and then says that one of them caused the other to occur.

Incorrect Answers

(B) is consistent with the original argument that says it is only microscopically detectable.
(C) would only suggest that it operates differently than other animals, not that it doesn't operate as a sensory organ.
(D) is similar to answer choice (C).
(E) would possibly support the argument if it was suggested that the enhancement was a result of the VNO being used a sensory organ.

[zainrizvi]

So one tactic espoused in the LR book is that if an answer choice can be "interpreted" in different ways to strengthen and weaken the argument, then it probably isn't a good answer choice.

For this answer, the fact that "it is not known" could be interpreted as eventually leading to 1) it being shown that it was not solely stimulating those cells (which weakens) OR 2) it being shown that it was solely stimulating those cells (which sort of strengthens). Based off this, I eliminated the answer choice...

I'm pretty sure I'm using the technique incorrectly but I just want to understand where..

[ManhattanPrepLSAT1]

You have a good understanding of the principle outlined in the LR Strategy Guide. I'd say the misunderstanding here falls into whether or not this answer choice could either strengthen or weaken the argument.

Consider that the argument is attributing causation to the VNO in humans. It's suggesting that the VNO is what caused the subjects to experience sensations of smell. A classic means of undermining such an argument is introducing the possibility of an alternative cause. Answer choice (A) calls into question whether it really was the VNO, but suggesting that it might have been been other cells that could have triggered the sensation of smell.

I agree the language "it is not known" is weak, but sufficient nonetheless to cast a shadow of doubt on the argument's conclusion.