Self-study
Some people have been promoting a new herbal mixture as a remedy for the common cold. ███ ███████ █████████ █████ █████ ███████ ████████ ██ ███ ██████ ██████ ██████████ ███ ███████████ █ ████ █████████ █████████ ██ ███ █████ ████ ███ ███████ ██ ██ █████████ ████ ███████ ███████ ████████ ████ ███ ███████ ████ ██ █████████ ████ ███████ █████ ████ ██████ ████ █████ ████ ██ ███████ ████████ ██ ███████ ████ ██████ █████████ ████ █ ████ █████ ██ █████ ███ ██████████ █████ █████ ███ ████ ██████ ███ ████ █████ ███ ██ ███ ███ ███ ████████ ██ ██ █████████ ███ ███████████
Summarize Argument: Counter-Position
The stimulus introduces an herbal mixture that some people have been advocating as an effective cold remedy. We're interested in the argument one cold sufferer uses to reject the claim that this remedy is effective. According to the cold sufferer, if this claim were true — i.e., if this mixture were actually effective — then most people with colds would be using it, since most people with colds want to recover quickly. But the cold sufferer points out that in fact, many people with colds don't use the mixture Therefore, the cold sufferer concludes, the mixture must not be an effective remedy.
Describe Method of Reasoning
To counter the claim that this cold remedy is effective, the cold sufferer sets up an argument involving conditional logic. He gives us the premise that most people with colds want to recover quickly. This idea is never disputed: it's taken as a "given" or a preliminary for the conditional argument that follows, but it's not itself one of the conditions in that argument.
The actual conditional argument runs like this: if this mixture were effective (a sufficient condition), almost all people with colds would be using it (a necessary condition). Since many people with colds are not using it (supposedly, the negation of the necessary condition), the mixture must not be effective (negation of the original sufficient condition). Basically, the cold sufferer is trying to make an argument using the logic of the contrapositive: if A, then B; but since /B, we have to conclude /A.
It's important to see that this argument is flawed. Saying that "many" people don't use the mixture isn't necessarily a negation of the statement "almost all people with colds use the mixture". Remember that "many" on the LSAT is an indefinite quantity similar to "some". The argument also relies on the assumption that people who want to recover from colds quickly would know that this mixture is effective. If they didn't know, then it wouldn't necessarily be true that they would nearly all be using it, even if it were effective.
But for this question, we're not trying to critique this argument. We just want to describe how the cold sufferer is trying to establish his conclusion. To sum up, then, he says that if claim A, the mixture being effective, were true, then B, most people with colds using the mixture, would also be true. But because B, in the cold sufferer's view, is not true, A must also not be true: i.e., the mixture is not an effective remedy.
21.
Which one of the following ████ ██████████ █████████ ███ ██████ ██ █████████ ███ ████ ████████ ████ ██ █████ ███ ██████████ ██ ███ █████████
a
finding a claim ██ ██ █████ ██ ███ ███████ ████ ██ █████ ██ ████ ████ ████████████ ████ ███ █████
This is correct. The cold sufferer is interested in showing that a certain claim is false: the claim that this mixture is an effective cold remedy. He does this by saying that if it were true, something else would happen or also be true: most people suffering from colds would use it. This, according to the cold sufferer, would be the consequence of the remedy actually being effective. But the cold sufferer then suggests that this consequence has actually not occurred: "many people" suffering from colds don't actually use the remedy. Since the consequence is false — i.e., it's not true that most people suffering from colds use this remedy — the cold sufferer concludes that the original claim is false.
b
accepting a claim ██ ███ █████ ██ ██████ ███████ ██ ███ █████
The cold sufferer's argument isn't structured as accepting a given claim, but as disproving a claim. He wants to disprove the idea that this mixture is an effective cold remedy. The cold sufferer also doesn't mention public opinion at all. He talks about what people would do if the remedy were effective, but this is different from talking about what most people currently think about the effectiveness of this mixture.
c
showing that conditions █████████ ██ █████████ ███ █████ ██ █ █████ ███ ███
This answer choice is worded to be tricky. It might be tempting because it mentions necessary conditions, and the cold sufferer's argument does focus on a "necessary condition." But the point of the cold sufferer's argument is that a necessary condition — the consequence that most people with colds would use the remedy — is not met, and therefore the sufficient condition is not true.
It's also important to catch another difference in the emphasis between what this answer choice is talking about — a necessary condition for knowledge, i.e. "what conditions need to be met so we can know or establish that a claim is true?" — and the cold sufferer's argument, which is only about "necessary conditions" insofar as it talks about logical consequences of a claim being true — i.e., "if this claim were true, what would necessarily also be true?" The cold sufferer says, "If the remedy were effective, then most people with colds would be using it." He doesn't say, "For us to establish that this remedy is effective, most people with colds must be using it." The arguments are related, but not the same. So this answer choice is just irrelevant.
d
basing a generalization ██ █ ██████████████ █████ ██ █████████
For this answer choice to work, you would need to treat the cold sufferer's conclusion — the mixture is not an effective remedy — as a "generalization." Even assuming that that's accurate, you would then have to say that the "many people" who do not use the mixture are the "representative instances" the generalization is based on. But we have no way of knowing if those "many people" are actually "representative" or not, nor does the cold sufferer's argument depend on them being "representative" in some broader sense. The "many people" only matter because, in the cold sufferer's view, they disprove the idea that "most people" with colds use the remedy. So this answer choice is inaccurate.
e
showing that a ███████ ███████ ██ ██ █████████ ██ █████████ █ ███████ ██████ █████ ████████ ████ █████████ ███ ██████ ████ █████████
This is inaccurate. The cold sufferer doesn't say that the mixture would make it more difficult for people with colds to recover. Rather, the cold sufferer is only arguing that the mixture is ineffective.