is necessary to pierce through the literal meaning to the real meaning, which the author has purposely disguised under an inexact form.
Logically the problem is very embarrassing: there is no fixed external criterion by which we can make sure of detecting an oblique sense; in the case of the hoax, which in the present century has become a branch of literature, it is an essential part of the author's plan to leave no indication which would betray the jest. In practice we may be morally certain that an author is not using an oblique sense wherever his prime object is to be understood; we are therefore not likely to meet with difficulties of this kind in official documents, in charters, and in historical narratives. In all these cases the general form of the document permits us to assume that it is written in the literal sense of the words.
On the other hand, we must be prepared for oblique senses when the author had other interests than that of being understood, or when he wrote for a public which could understand his allusions and read between the lines, or when his readers, in virtue of a religious or literary initiation, might be expected to understand his symbolisms and figures of speech. This is the case with religious texts, private letters, and all those literary works which form so large a part of the documents on antiquity. Thus the art of recognising and determining hidden meanings in texts has always occupied a large space in the theory of hermeneutic (which is Greek for interpretative criticism), and in the exegesis of the sacred texts and of classical authors.
The different modes of introducing an oblique sense behind