Flawed Parallel ReasoningDiff: Easy
Logic Breakdown
Passage Summary: If a mom's first baby is early, the second one usually is too. Jackie's second baby wasn't early, so the speaker thinks her first one probably wasn't early either.
Conclusion: It is likely that Jackie's first child was not born before its due date.
Reasoning: The argument assumes that because a first child being early makes a second child likely to be early, the reverse must also be true: if the second child was not early, the first child likely was not either.
Analysis: This argument commits a classic formal logic error known as 'denying the antecedent' or a 'mistaken contrapositive,' but with a probabilistic twist. It takes a conditional relationship (If A, then likely B) and incorrectly assumes that 'Not B' allows us to conclude 'likely Not A.' In reality, the 'likely' only flows in the direction of the original arrow. To find the parallel, look for an answer that starts with a 'most' or 'likely' conditional, observes that the second part didn't happen, and concludes that the first part likely didn't happen either.
Conclusion: It is likely that Jackie's first child was not born before its due date.
Reasoning: The argument assumes that because a first child being early makes a second child likely to be early, the reverse must also be true: if the second child was not early, the first child likely was not either.
Analysis: This argument commits a classic formal logic error known as 'denying the antecedent' or a 'mistaken contrapositive,' but with a probabilistic twist. It takes a conditional relationship (If A, then likely B) and incorrectly assumes that 'Not B' allows us to conclude 'likely Not A.' In reality, the 'likely' only flows in the direction of the original arrow. To find the parallel, look for an answer that starts with a 'most' or 'likely' conditional, observes that the second part didn't happen, and concludes that the first part likely didn't happen either.
Passage Stimulus
Passage Redacted
Unlock Full Passage9.The questionable reasoning in the argument above is most similar in its reasoning to which one of the following?
Correct Answer
C
C mirrors the flaw: If the first movie is a hit, likely the sequel is a hit; the sequel was not a hit; therefore the first probably wasn’t a hit. That’s the same mistaken probabilistic contrapositive as in the stimulus.
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