## June 2007, Logical Reasoning 2, Question 20

### Transcript

Question 20, when a question asks you to find flawed reasoning that is most similar to reasoning found in another argument, you're dealing with a parallel flaw question. Parallel flaw questions ask us to identify the flaw in the original argument, and then find another argument that has the same flaw. Of course, we can't find the flaw in the original argument until we understand it, which means breaking it down into its component parts, its conclusion and its evidence.

So in this argument, the conclusion is found in the first sentence, we should accept the proposal to demolish the old train station. The first piece of evidence is helpfully flagged by the evidence keyword because. Because the local historical society, which is opposed to it, well, they're dominated by people who have no commitment to long-term economic well-being. And getting rid of old buildings is good for economic well-being.

Now, the flaw in this argument is a fairly common one on the LSAT, the absence of evidence flaw. Just because you've disproved someone's evidence or disproved someone's argument, that doesn't mean that you've proven the opposite of what they believe. And that's exactly what this author just tried to do. There are some people out there who believe that we shouldn't demolish this train station.

Their argument is bad because they don't really understand economics. And on the basis of that, then hey, knock it down, do the opposite of what they said. So when we go to the answer choices, we're gonna be looking for an argument where somebody does that. So answer choice A, this answer is what we often call a same subject trap.

Safeguarding works of art is very similar to safeguarding buildings that have historical value, but the similarity extends only to the subject. The reasoning here isn't that there's a group who we should oppose and then do the opposite of what they say. It's just that we should do something, and there are some people who might not get it.

That's not similar, so it's not our answer. Go to B, B's also on the same subject, preserving your local heritage through documents of importance is very similar to preserving old buildings. But again, the reasoning isn't the same. There's no one in this argument that is opposed to the preservation, so it's not our match.

Go to answer choice C, weirdly, even though this answer is about haircuts, it's exactly what we want. We have one party, the beauticians, who are suggesting that their customers do something. We're attacking that argument by saying, well, they're just doing that to generate business for themselves.

And they're concluding the opposite, so you shouldn't have your hair cut twice a month. Each part has a corresponding part in the original argument, so this is our parallel answer. So let's just look at the other answers to see why they're wrong. Answer choice D is wrong because in this argument, the people are getting what they want.

They are opposed to the construction, and the committee is going to endorse the plan to postpone the construction. And this choice E is wrong because we don't have someone who we're opposing. Instead, we just have this chain of effect here, borrow a little bit of money, the debts pile up. So since the argument isn't similar, it's not our answer.