Name the mistake in the following: 'All textbooks are books meant for careful study. Some reference books are books meant for careful study. Therefore, some reference books are textbooks.'

AIllicit minor

BIllicit major

CUndistributed middle ✓ Correct

DFallacy of four terms

Correct answer: (C) Undistributed middle

Explanation

The error is an undistributed middle term.

The shared middle is 'books meant for careful study'.

In 'All textbooks are books for careful study' this middle is the undistributed predicate of an A proposition.

In 'Some reference books are books for careful study' it is again undistributed, as the predicate of an I proposition.

A middle never distributed cannot connect the two other terms.

The rule that the middle must be distributed at least once is thereby broken.

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