Which of the following statements are logically equivalent?

1.Some cricketers are kind men

2.Some kind men are cricketers

3.Some cricketers are not non-kind men

4.Some non-kind men are not non-cricketers

A2, 3 & 4 only

B3 & 4 only

C1, 2 & 3 only ✓ Correct

D1 & 4 only

Correct answer: (C) 1, 2 & 3 only

Explanation

Statements 1, 2 and 3 all express the same particular affirmative.

Some cricketers are kind men is the base I proposition.

Statement 2 is its converse, and an I proposition converts without loss of meaning.

Statement 3, some cricketers are not non-kind men, is its obverse, again equivalent.

Conversion and obversion preserve logical equivalence, so these three coincide in meaning.

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