In forming words by comparison, as by association, terms applicable literally to material conceptions alone come to refer after a time to those that are immaterial. Take words, for instance, describing the operations of the mind. We say that a man’s thoughts are pure, clear, mixed, muddled, or clouded, and that he expresses and impresses them upon others; but only to material things, like water, wine, or the atmosphere, can the former class of terms be applied literally; and only into or out of a material thing can another, and this only a material thing, be literally pressed. Evidently terms of this kind are used as a result of comparing the mental to the material process, to which in some regards it is analogous. Were it not possible to symbolize the one process in the other, it is obvious that many things which we desire to communicate, would remain forever unexpressed. We see, there-fore, how essential to the very existence of language is this power which enables us to figure or picture an object or operation through referring to something which, though like it in some respects, is wholly different from it in others; as different from it as the paint and canvas of a portrait are from the flesh and blood of the person portrayed. We see, too, how the element of representation, which is essential to all art, is a factor in the very constitution of language from which poetic art is developed. We see also how the means of representation are furnished mainly by the objects and operations of nature; and this not only by those appealing to the ear, the sounds of which can be imitated, but also by those appealing to the eye, the appearance of which suggests words like express and impress. Idem, XV.
Revelations, multiplied by almost the whole number of words employed, must flash light through all the hidden depths that underlie the surface forms of one’s vernacular, before he can understand them, and use them with absolute appropriateness. Especially is this so in the case of the words with which we are now dealing,the words formed as a result of comparison; because these contain, far more decidedly than those derived from association, a representative or picturesquewhat grammarians term a figurative element.Idem, XV.