Flawed ReasoningDiff: Easy
Logic Breakdown
Passage Summary: A scientist says everyone who got better took Medicine M. A reporter then claims this means that everyone who took Medicine M must have gotten better.
Conclusion: If a participant in the medical study was not cured of athlete's foot, then that person definitely did not take medication M.
Reasoning: In the study, the only participants who were actually cured were those who had been given medication M.
Analysis: The reporter is confusing a necessary condition with a sufficient one. The scientist established that Medication M was necessary for a cure (Cure -> Med M), but the reporter interprets this as Medication M being sufficient for a cure (Med M -> Cure). In logical terms, the reporter is incorrectly treating the contrapositive of the scientist's statement. Look for an answer that describes this 'mistaken negation' or the confusion between what is required for a result and what guarantees a result.
Conclusion: If a participant in the medical study was not cured of athlete's foot, then that person definitely did not take medication M.
Reasoning: In the study, the only participants who were actually cured were those who had been given medication M.
Analysis: The reporter is confusing a necessary condition with a sufficient one. The scientist established that Medication M was necessary for a cure (Cure -> Med M), but the reporter interprets this as Medication M being sufficient for a cure (Med M -> Cure). In logical terms, the reporter is incorrectly treating the contrapositive of the scientist's statement. Look for an answer that describes this 'mistaken negation' or the confusion between what is required for a result and what guarantees a result.
Passage Stimulus
Passage Redacted
Unlock Full Passage11.Which one of the following most accurately describes the reporter’s error in reasoning?
Correct Answer
A
A correctly identifies the error: concluding from evidence that shows only that M was necessary for cure in this study that M always cures (treating M as sufficient). This mirrors the reporter’s invalid inverse/necessity-to-sufficiency leap.
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