has been reckoned among the auxiliary sciences of history. To understand a text it is first necessary to know the language. But a general knowledge of the language is not enough. In order to interpret Gregory of Tours, it is not enough to know Latin in a general way; it is necessary to add a special study of the particular kind of Latin written by Gregory of Tours.
The natural tendency is to attribute the same meaning to the same word wherever it occurs. We instinctively treat a language as if it were a fixed system of signs. Fixity, indeed, is a characteristic of the signs which have been expressly invented for scientific use, such as algebraical notation or the nomenclature of chemistry. Here every expression has a single precise meaning, which is absolute and invariable; it expresses an accurately analysed and defined idea, only one such idea, and that always the same in whatever context the expression may occur, and by whatever author it may be used. But ordinary language, in which documents are written, fluctuates: each word expresses a complex and ill-defined idea; its meanings are manifold, relative, and variable; the same word may stand for several different things, and is used in different senses by the same author according to the context; lastly, the meaning of a word varies from author to author, and is modified in the course of time. Vel, which in classical Latin only has the meanings or and even, means and in certain epochs of the middle ages; suffragium, which is classical Latin for suffrage, takes in mediæval Latin the sense of help. We have, then, to learn to resist the instinct which leads us to explain all the