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

Question

Solve this multiple-choice question and choose the correct option.

Accepted Answer

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/ApproachPremise 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.DerivationFrom 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/AlternativeVenn viewpoint: the region Always successful is disjoint from Fools; Raman is placed in the Always successful region, so he is outside Fools.Common pitfallsIgnoring the exclusion and thinking both could hold together, which violates Premise 2.Final AnswerOnly conclusion II follows.

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

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