expressions of a text by their classical or ordinary meanings. The grammatical interpretation, based on the general rules of the language, must be supplemented by an historical interpretation founded on an examination of the particular case.
The method consists in determining the special meaning of the words in the document; it rests on a few very simple principles.
(1) Language changes by continuous evolution. Each epoch has a language of its own, which must be treated as a separate system of signs. In order to understand a document we must know the language of the time—that is, the meanings of words and forms of expression in use at the time when the text was written. The meaning of a word is to be determined by bringing together the passages where it is employed: it will generally be found that in one or other of these the remainder of the sentence leaves no doubt as to the meaning of the word in question. Information of this kind is given in historical dictionaries, such as the Thesaurus Linguæ Latinæ; or the glossaries of Du Cange. In these compilations the article devoted to each word is a collection of the passages in which the word occurs, accompanied by indications of authorship which fix the epoch.
When the author wrote in a dead language which he had learnt out of books—this is the case with the Latin texts of the earlier middle ages—we must be on our guard against words used in an arbitrary sense, or selected for the sake of elegance: for example, consul (count, earl), capite census (censitary), agellus (grand domain).
(2) Linguistic usage may vary from one region to another; we