Two of the most important characters of general terms are their logical breadth and depth. The breadth of a term in general is that of which the term can be predicated. [—] The breadth therefore may be considered as a collection of objects – real things – though it can also be considered as consisting of the terms which may be made subject of a true proposition of which the given term is the predicate.
The totality of the subjects, and also, indifferently, the totality of the real objects of a sign, is called the logical breadth.
…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.