Even the old critic who separated verse poetry from prose literature as a distinct branch of writing was always suspicious that he was in error, for he knew both were the products of creative imagination. Of the ancients, it was only Aristotle who, defining poetry as imitation, saw that he must include prose that "imitated" in his definition of poetry. The thing that counted was the imitation or imagination in determining poetry and not metre.
As imagination creates the literature of ecstasy, the real subject of this book has been the function of the imagination, but as the term, like poetry, has been so much abused and misunderstood, the nature of them both is studied by using other terms, like "ecstasy" and the "unconscious."
I suppose that no word has been more used in connection with poetry than the word imagination. And probably no word has been more vaguely and diversely employed. Every one agrees that literature in general must be the function of the imagination. Many people when they speak of imagination really mean nothing more than the introduction of numerous figures of speech; others confuse it with the sportive play of the author with supernatural machinery in his work. To others imagination suggests something that is opposed to the convictions of the intellect and to the moral faculty. Even to-day many people do not know that Aristotle used the term "imitation" and Bacon the word "feigning" where we use the word "imagination." These older terms, in the course of evolution in meaning which words undergo, are used by us no longer to represent poetic creation, or imaginative work.
Every one quotes the famous lines of Shakespeare in the fifth act of the _Midsummer Night's Dream_, and many fail to see the exact meaning of the master who had a true conception of the function of his art. First he recognizes that the poet is "imagination all compact," and compares him to the lunatic and the lover. Next he uses the word frenzy in speaking of the poet's eye which rolls about and glances over the universe, showing that he had the conception of the ecstatic element in the poet's make-up and work. The poet gives shape to the forms of unknown things bodied forth by imagination, he gives a local habitation and a name to airy nothing. Shakespeare recognizes the fact that imagination is related to the dream when he says that one of the tricks of imagination is that if it apprehends a joy, it comprehends the bringer of that joy, that is, it builds a dream castle where that joy is realized. His use of the words "unknown things" in addition, as the substance of imagination, shows that he understood that the realm of the unconscious was the province of the imagination. Hazlitt and Lowell among modern critics correctly understood Shakespeare's meaning of imagination as identical with ecstasy.[193:A]