Which of the following statements are logically equivalent? Choose the correct answer from the options given below.

1.No monkeys are felines

2.Some monkeys are felines

3.Some felines are monkeys

4.Some monkeys are not feline

A1 and 4 only

B2 and 3 only ✓ Correct

C2 and 4 only

D2, 3 and 4 only

Correct answer: (B) 2 and 3 only

Explanation

Statements 2 and 3 say the same thing because an I proposition converts without loss.

Statement 2 is 'Some monkeys are felines' and Statement 3 is 'Some felines are monkeys'.

Both are particular affirmative (I) propositions of the form Some S are P.

Simple conversion of an I proposition interchanges subject and predicate while keeping the truth value.

So the two statements always stand or fall together.

Their logical equivalence rests on the valid conversion of the I form.

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