What is spirit?  What are our own minds, the portion of spirit with which we are best acquainted?  We observe certain phenomena.  We cannot explain them into material causes.  We therefore infer that there exists something which is not material.  But of this something we have no idea.  We can define it only by negatives.  We can reason about it only by symbols.  We use the word, but we have no image of the thing; and the business of poetry is with images, and not with words.  The poet uses words, indeed; but they are merely the instruments of his art, not its objects.  They are the materials which he is to dispose in such a manner as to present a picture to the mental eye.  And if they are not so disposed, they are no more entitled to be called poetry than a bale of canvas and a box of colors to be called a painting.

Logicians may reason about abstractions.  But the great mass of men must have images.  The strong tendency of the multitude in all ages and nations to idolatry can be explained on no other principle.  The first inhabitants of Greece, there is reason to believe, worshipped one invisible Deity.  But the necessity of having something more definite to adore produced, in a few centuries, the innumerable crowd of gods and goddesses.  In like manner the ancient Persians thought it impious to exhibit the creator under a human form.  Yet even these transferred to the sun the worship which, in speculation, they considered due only to the Supreme Mind.  The history of the Jews is the record of a continued struggle between pure Theism, supported by the most terrible sanctions, and the strangely fascinating desire of having some visible and tangible object of adoration.  Perhaps none of the secondary causes which Gibbon has assigned for the rapidity with which Christianity spread over the world, while Judaism scarcely ever acquired a proselyte, operated more powerfully than this feeling.  God, the uncreated, the incomprehensible, the invisible, attracted few worshippers.  A philosopher might admire so noble a conception; but the crowd turned away in disgust from words which presented no image to their minds.  It was before Deity embodied in a human form, walking among men, partaking of their infirmities, leaning on their bosoms, weeping over their graves, slumbering in the manger, bleeding on the cross, that the prejudices of the Synagogue, and the doubts of the Academy, and the pride of the Portico, and the fasces of the Lictor, and the swords of thirty legions, were humbled in the dust.  Soon after Christianity had achieved its triumph, the principle which had assisted it began to corrupt it.  It became a new paganism.  Patron saints assumed the offices of household gods.  St. George took the place of Mars.  St. Elmo consoled the mariner for the loss of Castor and Pollux.  The Virgin Mother and Cecilia succeeded to Venus and Muses.  The fascination of sex and loveliness was again joined to that of celestial dignity; and the homage of chivalry