What are the two relationships categorical statements can have to one another?

• A. Opposition and Equivalence
• B. Causation and Correlation
• C. Implication and Converse
• D. Necessity and Contingency

Answer: (A)

Two categorical statements about the same terms relate in one of two broad ways: opposition and equivalence. Opposition covers how universal and particular forms line up—A and E are contraries that cannot both be true, while I and O are subcontraries that cannot both be false, and the pairs A with O and E with I are contradictories that cannot both be true and cannot both be false. Equivalence, on the other hand, means the two statements express the same claim and thus share the same truth value in every possible case, even if they’re worded differently. The other options point to relationships from different areas of logic (causation-correlation, conditional implications, or modal necessity-contingency) and don’t describe how two categorical propositions relate to each other in the traditional syllogistic framework.