Science therefore may in some measure modify Poetry, may enlarge its range, may reveal new phases of it, but can never supersede it. The imaginative view of things which Poetry expresses is not one which can grow obsolete. It is not the child of any one particular stage of knowledge or civilization, which can be put aside when a higher stage has been reached. Any state of knowledge can give scope to it. Any aspect of the world, that seen by the savage as well as that of the sage, can awaken that imaginative glow of mind, that thrill of emotion, which, expressed in fitting words, is called Poetry. Only, as has been said above, before any aspect of nature, or fact of life, or truth of science, may be capable of poetic treatment, it must have become habitual and easy to the mind of the poet, and in some measure to that of his audience. In the poet’s mind, at least, it must have passed out of the region of mere head-notions into the warmer atmosphere of imaginative intuition, and, vitalized there, must have bodied itself into beautiful form and flushed into glowing color. For, to repeat once again what has been said at the outset, Poetry originates in the vivid contact of the soul—not of the understanding merely, but of the whole soul—with reality of any kind; and it is the utterance of the joy that arises, of the glow that is felt, from such soul-contact with the reality of things. When that reality has passed inward, and kindled the soul to “a white heat of emotion,” then it is that genuine Poetry is born. CHAPTER V. HOW FAR SCIENCE MAY MODIFY POETRY. It may be worth while to dwell a little longer on the way in which Poetry and Science respectively deal with external Nature, noticing in what respects their methods agree, in what they differ, wherein they seem to modify each other, and how each aims at a separate and distinct end of its own.