For the reason, however, that the meaning that is thus rendered intelligible under the image only comes to light by virtue of the context, the significance which is expressed in metaphor cannot claim the importance of an independent artistic presentation; their mode of appearance is purely incidental, so that metaphors, in a still more emphatic degree, can only be employed as the external embellishment of an essentially independent work of art.
(_β_) The metaphor is mainly used in the expressions of speech, which we may usefully consider in this relation under the following aspects.
(_αα_) In the first place every language includes within its own compass a host of metaphors. They arise from the fact that a word, which in the first instance merely designates something entirely sensuous, is carried over into a spiritual sphere. "_Grasp"_, "_comprehend"_[92], and generally a number of words connected with the processes of thought, have in regard to their original meaning a content that is wholly sensuous, which is consequently abandoned and exchanged for the meaning applicable to mind; the first meaning is sensuous, the second spiritual.
(_ββ_) By degrees, however, the metaphorical aspect disappears in the general use of such a word, which as the current coin of language is converted from an expression which is not strictly accurate to one that is so, the effect of this process being that image and import, owing to the habitual frequency with which the latter is only conceived in the former, cease to differ from one another, and the image merely immediately presents the abstract significance itself instead of a concrete mode of vision[93].
When we take, for example, the word "grasp" in the sense applicable to mental life it entirely escapes us that there is any sensuous relation implied between the hand and external objects[94]. In living languages this distinction between genuine metaphor and words which already through usage have fallen to the level of a mere means of expression is readily established; the reverse is the case with dead languages, for the reason that here mere etymology is unable finally to bring our minds to a decision, inasmuch and in so far as the question does not depend on the original source of that word, and its general development in speech, but first and foremost on the fact whether a word which has all the appearance of being used in a picturesque and metaphorical sense had or had not already lost by habitual usage under a meaning applying exclusively to spirit, and in the speech when alive, its first sensuous significance and been absorbed wholly in that higher sense.