Syllogism – Shared superset without guaranteed overlap: Statements: (a) All poets are intelligent. (b) All singers are intelligent. Conclusions: I) All singers are poets. II) Some intelligent persons are not singers.
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AOnly conclusion I follows
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BOnly conclusion II follows
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CEither conclusion I or II follows
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DNeither conclusion I nor II follows
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EBoth conclusions I and II follow
Answer
Correct Answer: Neither conclusion I nor II follows
Explanation
Introduction / Context:Two different groups lie inside the same superset (Intelligent). The trap is to infer overlap where none is stated.
Given Data / Assumptions:
- Poet ⊆ Intelligent.
- Singer ⊆ Intelligent.
- No premise about Poet–Singer intersection or about the size of Intelligent.
Concept / Approach:(I) “All singers are poets” is unjustified: two distinct subsets of a superset can be disjoint. (II) “Some intelligent persons are not singers” is also not compelled: it is possible (though unlikely in reality) that every intelligent person is a singer in some models. Syllogism evaluates necessity across all models, not plausibility.
Step-by-Step Solution:Construct Model A: Poets and Singers are disjoint proper subsets of Intelligent. (I) fails; (II) holds here but is not necessary.Construct Model B: Intelligent = Singers, with Poets ⊆ Singers. (I) may still fail, but (II) fails because every Intelligent is a Singer. Because conclusions can flip, neither is necessary.
Verification / Alternative check:Necessity requires truth in all valid models. Since countermodels exist for both I and II, neither follows.
Why Other Options Are Wrong:They claim necessity where only possibility exists.
Common Pitfalls:Assuming “shared superset” implies overlap or non-overlap without explicit statements.
Final Answer:Neither conclusion I nor II follows.