QUESTION TEXT: An article claims that many medical patients have…
QUESTION TYPE: Necessary Assumption
CONCLUSION: We shouldn’t trust the anecdotal evidence that patients have an instinctual ability to foresee changes in their medical status.
REASONING: There was a rumor where people thought babies were more often born during full moons. As a result maternity room staff were more likely to remember busy nights during a full moon.
ANALYSIS: This argument makes an analogy to babies born during full moons. However, to do an analogy properly, you must parallel the relevant features. The moon-baby story had two features:
- A rumor that babies were born more often during full moons.
- This rumor messed with maternity workers’ memories.
The author’s argument about the instinctual ability only has a rumor, #1. To parallel the analogy, the author needs to assume that this rumor also messes with the memories of those reporting patient predictions about changes in their condition, #2.
___________
- This isn’t necessary. The argument is just saying not to trust the reports. It doesn’t matter if definitive proof that the reports are wrong comes soon or a bit later.
Negation: The reports will be disproven, but only over a medium timeframe. - CORRECT. This is the second element of the analogy. If this is true, the analogy works. If it isn’t true, then we have no basis for the analogy.
Negation: Medical staff are equally likely to remember predictions whether or not the predictions are successful. - It doesn’t matter if the patients were being serious. It matters if they were right. A patient could get an intuitive sense their condition was changing. They might think that was a flimsy basis and feel silly predicting it, but they’d still be right.
Negation: The patients were serious in their predictions. - It doesn’t matter if babies are less likely to be born during a full moon. All that matters is that babies are not more likely to be born during a full moon.
Negation: Babies are equally likely to be born during a full moon as during other times. - It rarely matters if a belief is widely held. We only care if an idea is correct.
Negation: Lots of people believe patients can predict changes in their condition.
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Muskan Sandhu says
I am wondering why isn’t it necessary to assume that the anecdotal claim will be/has been disproven by empirical evidence (option a)? Because if it isn’t disproven, then the author’s analogy will fall flat since a part of the analogy is also that the rumour about full moon babies was empirically disproven?
TutorRosalie (LSATHacks) says
A is talking about something that will happen in the world. Suppose I say “This bridge is faulty and will break someday”. A is the equivalent of saying “The bridge will break in the next week”. B is the equivalent of saying “There is, in fact, a problem with the bridge’s structure”.
B is about the author actually being right. A is about whether other people in the real world will prove the author right. The author can be right even if no one formally proves it.
We can predict that something like B would be the answer because a necessary assumption question has to target the gap between conclusion and premise. The premise in question here is an analogy regarding maternity room staff more likley to remember full mooon night births. Why does this analogy support the author’s stance that anecdotal evidence shouldn’t be trusted? Answer Choice A, regarding the article, is irelevant and doesn’t show how the analogy supports the author’s argument. The correct answer would say something about how just like staff remember full moon night births, they will also remember patients’ accurate predictions about changes in their medical statuses.
Ari says
Question about your negation of D. Wouldn’t it be more accurate to negate D as saying “babies are equally, IF NOT MORE, likely to be born during a full moon”? Because – to negate the claim that A > B, we really have to say A ≤ B – not just A = B. One side of this disjunct DOES create a problem for the evidence provided – as you’ve noted.
How do we resolve this discrepancy?
TutorLucas (LSAT Hacks) says
In the second sentence of the analysis for (D), the explanation states that “all that matters is babies are not more likely to be born during a full moon”. “Not more likely” includes the possibilities that you’ve mentioned, i.e. babies are less likely to be born during that time, or babies are equally likely to be born during that time. Both of these possibilities are potential negations of (D).
Regardless of which of the two potential negations of (D) that we plug into the argument, the argument does not fall apart. Let’s say babies are less likely to be born during a full moon. If anything, that would strengthen the argument, because it would demonstrate the inaccuracy of the widely held belief about the full moon being a busier time in the maternity room. The same applies if babies are equally likely to be born during that time.