What is a

*syllogism*, or a

*categorical syllogism*, or a

*syllogistic argument*?

Encyclopedias have long sections on the term. Gordon Clark’s definition from the Glossary of his Logic is a good one.

*Syllogism – An argument composed of two premises and a conclusion, with the predicate of the conclusion in one, the subject of the conclusion in the other, and a third term in the two premises. (Logic, Glossary, PB, p.123)*

The syllogism’s elements consist of three and only three propositions. Two of the propositions are reasons (premises) in support of the third proposition, the conclusion. These propositions share three terms in a definite arrangement.

The subject of the conclusion of the argument is the minor term, the predicate of the same proposition is the major term, and the middle term is in both premises but never in the conclusion.

The premise with the predicate term of the conclusion is the major premise.

The premise with the minor term, either as subject or predicate, is the minor premise.

A syllogism has 3 propositions: the major premise, placed 1st, the minor premise, placed 2nd, and the conclusion (placed 3rd).

- The major term located in the major premise and in the conclusion (the conclusion’s predicate term).
- The minor term is located in the minor premise and in the conclusion (the conclusion’s subject term).
- The middle term is located in the major premise and the minor premise, never in the conclusion.