of two premises, though it may consist of several premises.”
The reply is:
“This contradicts what is in your books, for you allow only two premises.”
They have expressly stated that a syllogism yielding the desired conclusion, whether conjunctive or exceptive, consists of neither fewer nor more than two premises. They justify this by saying that a single conclusion has no more than two parts: a subject and a predicate.
If the syllogism is conjunctive, each of the two parts of the conclusion must correspond to one of its premises—that is, it must occur within that premise as either its subject or its predicate, without itself constituting the entire premise.
They say:
“The conclusion has no more than two parts and therefore requires no more than two premises. If the syllogism is exceptive, it must contain a conditional premise, either implicative or disjunctive, corresponding to the whole conclusion or its contradictory. It must also contain an exceptive premise, so there is no need for a third.”
They say:
“However, a statement additional to the syllogism’s two premises may sometimes be incorporated into it. This is either unrelated to the syllogism or related to it. If related, it serves either to make the discourse more persuasive and polished or to explain both premises or one of them.”
They call this a compound syllogism.
They say:
“In essence, it amounts to several syllogisms presented to establish a single conclusion. Of these, however, only one directly establishes the desired conclusion, and the rest