n. (Logic) 1.a deductive inference consisting of two premises and a conclusion, all of which are categorical, that is, relate two predicates. The premise in which the predicate of the conclusion (the major term) occurs is the major premise, and that in which the subject of the conclusion (the minor term) occurs is the minor premise; the middle term occurs in both premises but not the conclusion. There are 256 syllogisms categorized in four figures, but only 24 are valid; for example, is invalid, while is valid. Here fascinating, in ruins, and temple are respectively the major, middle and minor terms. 2. deductive inferences of certain other forms with two premises, such as the hypothetical syllogism.