Flawed Parallel ReasoningDiff: Hardest
Logic Breakdown
Passage Summary: The host believes her party will definitely be great because she has plenty of snacks and every person she invited is nice.
Conclusion: Sylvia's dinner party is guaranteed to be a success.
Reasoning: A successful party is ensured by congenial guests and plenty of food, and Sylvia has both individual congenial guests and an abundance of food.
Analysis: This argument commits a classic 'Error of Composition.' It assumes that because every individual guest is congenial, the group as a whole will be congenial. We all know that putting ten lovely people in a room doesn't guarantee a 'congenial' atmosphere—sometimes personalities just don't click. To find the parallel flaw, look for an answer that takes a property of individual parts (the guests) and attributes it to the whole (the party). It's the logical equivalent of saying that because every ingredient in a dish is delicious, the final meal is guaranteed to be a masterpiece.
Conclusion: Sylvia's dinner party is guaranteed to be a success.
Reasoning: A successful party is ensured by congenial guests and plenty of food, and Sylvia has both individual congenial guests and an abundance of food.
Analysis: This argument commits a classic 'Error of Composition.' It assumes that because every individual guest is congenial, the group as a whole will be congenial. We all know that putting ten lovely people in a room doesn't guarantee a 'congenial' atmosphere—sometimes personalities just don't click. To find the parallel flaw, look for an answer that takes a property of individual parts (the guests) and attributes it to the whole (the party). It's the logical equivalent of saying that because every ingredient in a dish is delicious, the final meal is guaranteed to be a masterpiece.
Passage Stimulus
Passage Redacted
Unlock Full Passage22.The pattern of flawed reasoning exhibited by the argument above is most similar to that exhibited by which one of the following?
Correct Answer
D
D presents: (Well-seasoned stock ∧ Fresh ingredients) → Welcome soup. The case only establishes fresh ingredients and then concludes the soup will be welcome, ignoring the well-seasoned stock requirement. That matches the original flaw of concluding the guaranteed result while failing to secure one conjunct of the sufficient condition.
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