Which of the following statements is equivalent to the statement 'Some non-realists are not non-philosophers'?

ASome philosophers are not realists ✓ Correct

BNo philosophers are realists

CSome realists are philosophers

DSome philosophers are realists

Correct answer: (A) Some philosophers are not realists

Explanation

The equivalent is 'Some philosophers are not realists', reached by full contraposition.

The given form is O: Some non-realists are not non-philosophers.

Full contraposition of an O turns 'Some S are not P' into 'Some non-P are not non-S'.

Here non-P becomes philosophers and non-S becomes realists.

This yields 'Some philosophers are not realists', logically equivalent to the original.

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