Thank Heaven, we have not yet come to think that the highest form of wisdom is enshrined in the _sesquipedalia monstra_ of chemical formulae, still less in the extreme abstractions of mathematics. Not that such formulae have not a beauty, and even a Mysticism of their own; their harmfulness comes from the exclusiveness of their claims when they are advanced as an adequate description (sometimes explanation!) of existence at large and of life in particular. The biological formulas, based on mathematics, at which Le Dantec, for instance, has arrived, if taken at their author's valuation, and if consistently applied, would make the sublimest poetry to be greater folly than the babble of a child. The nature-mystic may, or may not, allow them a relative value according as he considers them to be valid or invalid abstractions from observed facts; but he knows that the most valid of them are exceedingly limited in their scope and superficial in their bearing: and it remains a standing wonder to him that any trained intellect can fail to realise their miserable inadequacy, in view of the full rich current of living experience. One of the chief merits of genuine nature-poetry is that it keeps us in close and constant touch with sense experience, and at the same time brings home nature's inner life and meaning. It is not a mere string of metaphors and symbols based on accidental associations of ideas, but an expression and interpretation of definite sensations and intuitions which result from the action of man's physical environment upon his deepest and most delicate faculties. "High art" (says Myers) "is based upon unprovable intuitions; and of all arts it is poetry whose intuitions take the brightest glow, and best illumine the mystery without us from the mystery within." But more especially, poetry is essentially animistic. It produces its characteristic effect by creating in the mind the sensuous images which best stimulate the mind to grasp the immanent idea, and it presents those images as instinct with life and movement--sometimes it goes so far as to personify them. This is what Matthew Arnold meant when he declared poetry to be "simple, sensuous, passionate." Coleridge has a good illustration (quoted by Nisbet). He observes that the lines: "Behold yon row of pines that shorn and bowed Bend from the sea-blast, seen at twilight eve"-- contain little or no poetry if rearranged as a sentence in a book of topography or description of a tour. But the same image, he says, rises into the semblance of poetry if thus conveyed: "Yon row of black and visionary pines By twilight glimpse discerned! Mark how they flee From the fierce sea-blast, all their tresses wild Streaming before them."