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June 2007, Logical Reasoning 1, Question 21


Question 21. When a question asks you for the criticism that an argument is vulnerable to, that makes it's a flaw question. In a flaw question, you have to find the error in the argument. In order to find the error in the argument, you need to know the argument's conclusion and its evidence.

Here, the conclusion is helpfully flagged by the key word so. So trading in my sports car for a minivan would lower my risk of having an accident, this says a driver who drives a sports car. Which, we find out in the first sentence not only drives it, but drives it recklessly. The second sentence gives us the other piece of evidence.

The driver has done some research and found out that minivans have a much lower accident rate, compared to sports cars. That's why the driver believes that trading in the sports car is gonna lower the accident risk. Now, a flaw here is a pretty common one on the outset. It's confusing correlation and causation.

And what we mean by that is, in this argument, minivans are correlated with a low accident rate. In other words, minivans don't tend to get into too many accidents. But the argument relies on the assumption that the reason they don't get into accidents is because the minivans themselves are safe. That essentially, the minivan is causing the safety rate, which could be true, but doesn't have to be true.

They're linked in some way, minivans and safety. And it could be that minivans are just safer cars. But it could also be that the people who tend to drive minivans tend to be safer people. Soccer moms and such driving around in minivans tend to take fewer risks than people who drive in sports cars and drive recklessly.

So just because two things are connected, doesn't mean that one cause the other. There could be some other cause, or it could be a coincidence. We're gonna look in the answer choices for something that says that. Answer choice A infers a cause from a mere correlation. That's exactly what we just said the flaw was, so that is the answer. It thinks that minivans are definitely gonna lower the risk from the correlation that minivans and sedans have low accident rates.

So let's look at the other answers to see why they're wrong, but A is definitely right. Answer choice B relies on a sample that's too narrow. Well, we don't know what sample the argument's based on. All we know is it's based on some research. We don't know the source of that research, so we don't know what kind of sample it was using.

Answer choice C misinterprets evidence that a result is likely as evidence that result is certain. Well, the driver actually never concludes that a result is certain. The driver says that their risk is going to be lowered. That's not saying that they're not gonna get in any accidents certainly, just that it's less likely.

Answer choice D, mistakes a condition sufficient for bringing about a result for a condition necessary for doing so. There is a sufficient, or at least a quasi sufficient idea here. The minivan, the argument is arguing would be sufficient to bring their risk down. But at no point does this say that the minivan would be necessary to do that. Since the argument never says it's necessary, we can't accuse it in the answer choices of confusing sufficiency and necessity.

And answer choice E relies on source that is probably not well-informed. Certainly, the driver doesn't seem like a very well-informed individual, but that would just be my impression. I'd be basing that off of the idea that people who drive their cars recklessly don't tend to be informed, which I don't know. All I know is that the driver has done some research.

I don't know if it was good or bad research. I don't know if they're well-informed or not. So answer choice E is not the answer, it is A.

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