…it was between six and seven centuries ago that John of Salisbury spoke of it as “fere in omnium ore celebre.” It is the distinction, to use that author’s phrases, between that which a term nominat – its logical breadth – and that which it significat – its logical depth. In the case of a proposition, it is the distinction between that which its subject denotes and that which its predicate asserts. In the case of an argument, it is the distinction between the state of things in which its premisses are true and the state of things which is defined by the truth of its conclusion.