Flawed Parallel ReasoningDiff: Hardest
Logic Breakdown
Passage Summary: Two theories agree on the past but disagree on the future, so the next test will definitely show which one is right and which is wrong.
Conclusion: The results of the upcoming experiment will prove one of the two theories to be correct and the other to be incorrect.
Reasoning: While current evidence supports both theories, they make mutually exclusive predictions about the outcome of a future experiment.
Analysis: The flaw here is a false dilemma; the author assumes that because the two theories disagree, one of them must be the truth. In reality, the experiment could yield a result that proves both theories are actually wrong. To match this pattern, look for an answer choice that takes two conflicting possibilities and concludes that the truth must reside in one of them, ignoring a third option where both are false.
Conclusion: The results of the upcoming experiment will prove one of the two theories to be correct and the other to be incorrect.
Reasoning: While current evidence supports both theories, they make mutually exclusive predictions about the outcome of a future experiment.
Analysis: The flaw here is a false dilemma; the author assumes that because the two theories disagree, one of them must be the truth. In reality, the experiment could yield a result that proves both theories are actually wrong. To match this pattern, look for an answer choice that takes two conflicting possibilities and concludes that the truth must reside in one of them, ignoring a third option where both are false.
Passage Stimulus
Passage Redacted
Unlock Full Passage22.The argument above exhibits an erroneous pattern of reasoning most similar to that exhibited by which one of the following?
Correct Answer
E
E is parallel: David says beech; Jane says elm; the expert Maria will “verify either David’s or Jane’s opinion.” This assumes the expert’s verdict must align with one of the two incompatible options, ignoring the possibility it’s a different species or inconclusive—exactly the same erroneous either/or assumption.
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