Necessary AssumptionDiff: Hardest
Logic Breakdown
Passage Summary: People think patients can sense when their health is about to change, but that's probably just because doctors only remember the times the patients were right and ignore the times they were wrong.
Conclusion: The evidence suggesting patients have an instinctual ability to predict medical changes is unreliable.
Reasoning: The evidence is anecdotal and likely subject to the same memory bias as the full moon baby rumor, where people only remember the 'hits' and forget the 'misses.'
Analysis: The argument relies on an analogy between medical staff and the observers of these 'instinctual' patients. For this comparison to work, the author must assume that the observers of these patients are actually experiencing the same 'confirmation bias' mentioned in the full moon example. The 'Gap' is the assumption that there are many instances where patients *failed* to predict changes, but those instances were simply forgotten. Look for an answer that states observers are more likely to remember successful predictions than unsuccessful ones, as this is the 'Necessary' link for the analogy to hold.
Conclusion: The evidence suggesting patients have an instinctual ability to predict medical changes is unreliable.
Reasoning: The evidence is anecdotal and likely subject to the same memory bias as the full moon baby rumor, where people only remember the 'hits' and forget the 'misses.'
Analysis: The argument relies on an analogy between medical staff and the observers of these 'instinctual' patients. For this comparison to work, the author must assume that the observers of these patients are actually experiencing the same 'confirmation bias' mentioned in the full moon example. The 'Gap' is the assumption that there are many instances where patients *failed* to predict changes, but those instances were simply forgotten. Look for an answer that states observers are more likely to remember successful predictions than unsuccessful ones, as this is the 'Necessary' link for the analogy to hold.
Passage Stimulus
Passage Redacted
Unlock Full Passage18.The argument requires the assumption that
Correct Answer
B
This supplies the needed memory-bias link in the medical context: if predictions are less likely to be remembered when no change occurs, then anecdotes will overcount successes, making the evidence untrustworthy. Negation test: if predictions are just as likely to be remembered even when no change occurs, the selection-bias explanation collapses, and the argument’s basis for distrusting the anecdotes is undermined—so B is necessary.
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