What is the role of the middle term in a valid syllogism?

• A. It appears in both premises but not in the conclusion
• B. It appears only in the conclusion
• C. It appears in one premise and the conclusion
• D. It is the major term

Answer: (A)

The middle term functions as the bridge that links the two premises, connecting the subject term (the thing the argument is about) to the predicate term (the claim about that thing) without itself appearing in the conclusion. In a valid syllogism the chain runs from the subject through the middle term to the predicate, so the conclusion states a relationship between the subject term and the predicate term, not involving the linking term itself. For example: All dogs are mammals; All mammals are animals; therefore, All dogs are animals. Here the middle term is mammals, appearing in both premises to connect dogs to animals, but it does not appear in the conclusion. This setup preserves a proper logical flow: the subject is related to the middle term, which is related to the major term, yielding a relation between the subject and major terms in the conclusion.