PrepTest 144, Section 2, Question 18
An article claims that many medical patients have(64 more words not shown)
The argument requires the assumption(1 more words not shown)
- Athe article claiming(17 more words not shown)
- Bpatients' predictions of(21 more words not shown)
- Cthe patients in(15 more words not shown)
- Dbabies are less(19 more words not shown)
- Ethe idea that(20 more words not shown)
Reading the argument
Remembering the successful predictions isn't enough. What happened to the predictions that were wrong?
The author distrusts anecdotes about patients sensing changes in their medical status and compares them with the full-moon birth story. Maternity staff remembered busy nights with full moons more readily than equally busy nights without them. A selective collection of memories made a pattern seem real even though the claim had been disproven.
Think about learning a new word and suddenly noticing it everywhere. The word may not have become more common; you're now paying attention to it. Something similar can happen when people remember events that fit an expected pattern and overlook events that don't.
What we’re looking for
The analogy suggests that the patients' apparent predictive ability could also reflect selective memory. But the passage doesn't spell out exactly how that would work. For the necessary-assumption question, I want the connection that lets the author transfer the concern about the full-moon stories to the medical predictions.
Working the answers
- A
Distrusting the evidence doesn't require predicting that someone will soon disprove the article. Perhaps nobody conducts the needed research for years. The argument is about the reliability of the existing anecdotes, not the schedule or outcome of a future investigation.
- BCorrect
Medical staff would be more likely to remember a prediction followed by an actual change than one followed by no change. That would preserve the apparent successes while letting the failures fade, creating the same kind of misleading pattern as the full-moon memories.
The reference to staff may initially seem more specific than the article's description. But this is the missing connection in the author's analogy: the medical anecdotes are subject to a comparable pattern of selective recollection. The answer supplies that assumption rather than repeating a fact already stated. Without the selective forgetting of unsuccessful predictions, the full-moon example wouldn't give us the same reason to distrust this evidence.
- C
The patients could be completely serious and still make predictions whose apparent success is exaggerated by selective memory. The argument doesn't depend on patients joking or deliberately saying something they don't believe.
- D
Disproving unusually high numbers of births during full moons doesn't establish unusually low numbers. The rate could be the same as on other nights. The analogy depends on misleading recollection, not on a lower full-moon birth rate.
- E
We don't need to know how widely the belief is held. A popular belief could be supported by unreliable anecdotes, and so could an obscure belief. In fact, the comparison describes a rumor becoming popular. The argument doesn't require the medical belief to be unpopular.
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