Q16 - Scientist: An orbiting spacecraft detected a short-ter

[ohthatpatrick]

Question Type:
Weaken

Stimulus Breakdown:
Conclusion: We can't be sure that volcanic activity caused the spike in sulfur dioxide on Venue.
Evidence: Yes, volcanoes spew sulfur dioxide and Venus seems to have had some active volcanoes in the past. But, we haven't found any active volcanoes and atmospheres sometimes just have cyclical variations in chemical composition.

Answer Anticipation:
This falls into the ol' bucket of Causal Explanations.
There's a curious fact: "WHY is Venus's atmostphere suddenly higher in sulfur dioxide?"
The author offers her causal interpretation: "It's might not be from a volcano, since we don't know of any active volcanoes on Venus and it's possible that this is just a planet's atmosphere going through a cyclical variation."

To weaken, we want to pick an answer that either sounds like the sulfur dioxide IS from a volcano, or sounds like it's implausible that this spike in sulfur dioxide is a cyclical variation in atmosphere.

Correct Answer:
A

Answer Choice Analysis:
(A) Oh, boy. This is the correct answer, but I can see almost all of us ditching it on the first pass. I came back to it once all the others failed me. The author has two premises for why we shouldn't conclude that volcanoes are the cause. One of them is that no active volcanoes have been identified on Venus. (A) lessens the power of that premise by showing us that "even if there WERE volcanoes going off, we wouldn't be able to directly detect them". So the fact that we're NOT directly detecting active volcanoes shouldn't count as a strike against the volcano theory.

(B) This could strengthen the author's hypothesis that the spike is a cyclical variation (or it could mean there wa volcanic activity 30 years ago too). So, it's not clear what impact it has.

(C) A comparison to Earth's atmosphere is pointless. Earth was only brought up to explain that we have evidence that volcanoes CAN cause a spike in sulfur dioxide in a planetary atmosphere.

(D) This would probably strengthen. "IF it's a volcano, the spike in sulfur dioxide might last for years". Since the spike we observed on Venus is a short-term spike, then it probably wasn't caused by a volcano.

(E) This seems extremely irrelevant. Who cares what causes 51%+ of sulfur dioxide spikes on Earth?

Takeaway/Pattern: I'm pretty sure people will use the forum thread on this problem to vent how much they hate LSAT and how much this is a crappy question (I could be wrong). And I'm pretty sure I'll be talking those people off the ledge saying, 'remember, Strengthen/Weaken is about making the argument more or less convincing, not about proving or refuting the argument'. This correct answer clearly doesn't refute anything, but it weakens the value of one of the author's two premises. If I were building a murder case based on fingerprints and eyewitness testimony, if the defense attorney manages to make my eyewitness testimony seem non-compelling / inconclusive, then she has definitely weakened my case.

[AJE770]

Thanks for this. Is there a difference between premise weakening and premise boosting? Meaning, is it fair to say that for weakener questions, attacking a premise could be a correct answer choice, but we should be more skeptical of premise boosting for strengthener questions?

[egonza14]

I chose E by process of elimination and it is in line with what I thought the flaw would be. “What if the apartments are all in one old house? What if they’re in just a few of the houses, and the houses have room for like 4 or more apartments?” These thoughts would fault the conclusion.

What turned me OFF to E, and had me doubting my choice, was the use of the word “significant” in the answer choice. The choice says that the argument fails to consider that a significant number of old houses contain three or more apartments.” I took significant to mean something like Most. Which would then fall in line with the conclusion the author reached. Then I said maybe this significant number could just be half. Like let’s say there are 10 OHs and 20 A’s. If 5 of the OHs had 3 A each (15As) and the other 5 OHs only had one A each, that would fall in line with the answer choice. Half seems pretty significant to me.

That’s how I ended up choosing the answer, but I just want to make sure I don’t make similar errors/pauses/doubts in the future. Would you be able to provide some feedback? Thanks!

[ohthatpatrick]

It looks like you're posting on the wrong thread. This question is about volcanoes on Venus.

Can you doublecheck the test / section / number and re-post your question in the appropriate thread?

[TheGoodLife180]

Ill be the one ,however late, to complain about this crappy question. I left this one blank because nothing made sense. The explanation is cute but why am i expected to understand the part of the stimulus about the lack of identification as a premise for there not being any volcanic activity rather than thinking that its just a lack of evidence for the positive... nowhere does it say that the lack of evidence is evidence of there not being any activity and if that was the way it was understood then this isn't a weakening but a "spot the flaw" because the argument isn't weakened but rather its destroyed because it treats a lack of evidence as evidence of the contrary

[Theodore S K525]

Hi I have a question,

Doesn’t this involve assuming the first premise is not true?

Because we are saying that the first premise fails to consider this possibility that perhaps we can’t detect volcanos in Venus’ current conditions.

[IsaacB198]

The first premise: "no active volcanoes have been identified on Venus" is something that we take for granted as true. This does not mean the same thing as "there are no active volcanoes on Venus", but to get to our conclusion we would want that to be true. The gap between those two is an assumption that the argument is making, and the correct answer choice widens that gap, thus weakening the argument.