If there's any Logical Reasoning question that should teach you how to properly call "bullshit," it's this one. The key is the very first word: "Advertisement." If you can't learn to argue with ads--which everyone knows and expects to be bullshit--you simply might not be cut out to be a lawyer. You must argue! Section 3, question number 8 on the June 2007 LSAT talks about a supposed "test" conducted by the Fabric-Soft corporation. They used over 100 consumers -- which seems like a decent sample size -- and asked them which towel they preferred: A towel washed with Fabric-Soft, and a towel washed without Fabric-Soft. Surprise surprise, the consumers preferred the towel washed with Fabric-Soft! Therefore, the advertisement concludes, Fabric-Soft is the best. Aren't you surprised that they reached that conclusion? You're shocked, right? Tell me you're shocked.
No, of course you're not. It's fairly obvious here that Fabric-Soft has gamed the test in their own favor. How do you think they did it?
I have a couple ideas here: First, maybe they washed one towel in Fabric-Soft, and washed the other towel in horse urine. We aren't told that that didn't happen, which means it's possible. And if they really did wash the other towel in horse urine, the study only proves that people like Fabric-Soft better than horse urine--not that Fabric-Soft is actually the best.
Another possible trick, and this is something more subtle, is that the 100 consumers in the study might have been used to Fabric-Soft. Their grandmothers had used it, their mothers had used it--they'd been smelling Fabric-Soft every day of their lives for 50 years. If that were true, might it also be true that they'd prefer Fabric-Soft even if it smells like ass to anyone who isn't used to it? In this scenario, the test hasn't proved that Fabric-Soft is objectively the best; rather, it has proved that these 100 people are used to Fabric-Soft and therefore prefer it to other fabric softeners.
Armed with a couple objections, it's time to read the question. The question says
The advertisement's reasoning is most vulnerable to criticism on the grounds that it fails to consider whether...
This is a Flaw question. We need an answer choice that points out a reason why the test might not really prove that Fabric-Soft is best. No problem, since we've already spelled out two objections above. Time to check out the answer choices.
A) Nah, I don't think allergies are relevant here. And even if allergies were relevant, this answer choice wouldn't show whether Fabric-Soft specifically gives people allergic reactions... this answer choice is only about the broad category of "fabric softeners." Even if all fabric softeners, including Fabric-Soft, gave people immediate outbreaks of hives all over their bodies, Fabric-Soft could still be the best fabric softener.
B) This is a trap. The fact that you believe that the environment is important doesn't mean the environment is relevant when deciding on the most effective fabric softener. The argument specifically used softness and smell to argue that Fabric-Soft is the best. I'd really prefer an answer that points out that the test might have been slanted in some way, so that Fabric-Soft might not actually be the softest or the best-smelling.
C) Same explanation as A and B. Cost isn't relevant, if cost wasn't used in the argument. Anyway, who is to say whether cheaper or more expensive is better? I'd prefer something cheaper, all else equal, but then again more expensive things might be more expensive because they are better quality.
D) No, the argument is not about the use of fabric softeners vs. no fabric softeners at all. It's about whether Fabric-Soft is the best fabric softener.
E) Ahhh... finally. The advertisement said one towel was washed with Fabric-Soft, and the other one was washed "without." This means the other towel might have been washed in plain water, or in horse urine. If either of those two things are true, then how could we possibly know that Fabric-Soft is the best fabric softener? Our answer is E, because it points out a devastating hole in the argument.
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