QUESTION TEXT: A leading critic of space exploration…
QUESTION TYPE: Flawed Reasoning
CONCLUSION: A catastrophe is unlikely during the entire journey.
REASONING: A catastrophe is unlikely during any individual stage of the journey.
ANALYSIS: This argument makes a part-to-whole flaw. There could be 1,000 stages of the journey. A small likelihood of catastrophe at each individual stage could add up to great danger.
Hopefully this analogous argument makes it easier to see the flaw: “If you speed through city streets while drunk, an accident is unlikely on any given stretch of road. So you’re not likely to have an accident at any point while drunk driving.”
B, C and D are practically the same answer. They simply don’t happen in the stimulus. An answer has to happen for it to be a flaw.
___________
- CORRECT. The evidence is about the stages (the parts of the journey). The conclusion is about the whole journey.
- The conclusion didn’t say a catastrophe was impossible.
Example of flaw: A catastrophe is unlikely. So traveling to Mars is 100% safe, accidents are impossible. - This is almost exactly the same as B. The argument didn’t say that the trip would definitely work.
Example of flaw: The trip will probably be safe. So it will be. - The same as B and C. The argument didn’t say this!
Example of flaw: This rocket has a 1% chance of reaching Mars. So it will reach Mars, we’re 100% certain. - A conclusion can be right even if the evidence is wrong. This is a common flaw on the LSAT, but it doesn’t happen here.
Example of flaw: Critics said a Mars journey is dangerous, but their evidence is flawed. So traveling to Mars is certainly safe.
Recap: The question begins with “A leading critic of space exploration”. 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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Ryan says
I answered D on this one because the argument relies on the assumption that the backup systems would work, but that might not be justified given current technology. Just because something (backup system) COULD work, doesn’t mean it will. Am I wrong because that reasoning isn’t explicit in the stimulus?
Farid says
If the conclusion sentence is indeed the last one (“A fatal catastrophe is quite unlikely at any given stage if such a backup system is in place.”), to me that seems very different than the conclusion that you’ve paraphrased “A catastrophe is unlikely during the entire journey.” because they seem to be talking about “any given stage” even in the main point. What makes it so that it goes from ‘any given stage’ to ‘entire journey’ in that sentence?
This one is giving me trouble for that main reason and it seems like it’s hard to go with A because of this “jump” in understanding.
TutorLucas (LSAT Hacks) says
The conclusion isn’t the last sentence of the stimulus — the last sentence is actually a premise. The conclusion is actually contained within the first two sentences, particularly the second sentence, “but that exaggerates the risk.” The explanation is simply summarizing the first two sentences: “a catastrophe is unlikely during the entire journey.”
Shana says
Hi Graeme. I am still confused as to why D is incorrect. The way I see it, the argument could also be flawed in that it takes for granted that having a back-up system in place ensures that a fatal catastrophe is unlikely. To me, the flaw lies in the fact that having a back-up system cannot in itself guarantee safety.
Ultimately, I can understand from your explanation why A might be one possible correct answer, but the first time I read this stimulus, I did not see the same flaw as you did. How can I train my mind to think along the same lines as you did?
FounderGraeme says
The stimulus said a fatal catastrophy is “quite unlikely”. That doesn’t describe what D is saying.
Example of stimulus: It’s very unlikely a car will crash through my window. So I probably will be safe from that threat
Example of D: Wearing a nice shirt might help me get hired. So wearing a nice shirt will 100% lead to my being hired.
The argument DID NOT say the backup system would definitely work. They just said the risk is exaggerated. So it doesn’t match D.