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Immediate inference with an exclusion premise: ‘‘Raman is always successful’’ and ‘‘No fool is always successful’’ — decide which conclusion about Raman logically follows.

Difficulty: Easy

Correct Answer: Only conclusion II follows

Explanation:

Map the universal negative to Raman.

  • Premise 1: Raman is always successful.
  • Premise 2: No fool is always successful.
  • Conclusions: I. Raman is a fool. II. Raman is not a fool.

Concept/Approach
Premise 2 states that membership in the class Fools excludes being always successful. Since Raman is always successful, Raman cannot be a member of that class.
Derivation
From Premise 2: Fool ⟶ Not always successful. Contrapositive style reading with Raman being always successful gives: Raman is not a fool. So II follows, I does not.
Verification/Alternative
Venn viewpoint: the region Always successful is disjoint from Fools; Raman is placed in the Always successful region, so he is outside Fools.
Common pitfalls
Ignoring the exclusion and thinking both could hold together, which violates Premise 2.
Final Answer
Only conclusion II follows.
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