We call this divine power to discern beauty in every manifestation of the Deity, imagination. As it expresses itself in painting, it is so closely allied with what is highest and holiest in our natures that painting has come to be esteemed a Christian art, as contrasted in its development subsequent to the Christian era with the less human works of sculpture. "Christianity came, and instead of physical beauty substituted moral beauty, infinitely preferring the expression of the soul to the perfection of the body. Every man was great in its eyes, not by his perishable members, but by his immortal soul. With this religion begins the reign of painting, which is a more subtle art, more immaterial, than the others--more expressive, and also more individual. We will give some proofs of it. Instead of acting, like architecture and sculpture, upon the three dimensions of heavy matter, painting acts only upon one surface, and produces its effects with an imponderable thing, which is color--that is to say, light. Hegel has said with admirable wisdom: 'In sculpture and architecture forms are rendered visible by exterior light. In painting, on the contrary, matter, obscure in itself, has within itself its internal element, its ideal--light: it draws from itself both clearness and obscurity. Now, unity, the combination of light and dark, is color.' The painter, then, proposes to himself to represent, not bodies with their real thickness, but simply their appearance, their image; but by this means it is the mind which he addresses. Visible but impalpable, and in some sense immaterial, his work does not meet the touch, which is the sight of the body: it only meets the eye, which is the touch of the soul. Painting is then, from this point of view, the essential art of Christianity.... If the painter, like Phidias or Lysippus, had only to portray the types of humanity, the majesty of Jupiter, the strength of Hercules, he might do without the riches of color, and paint in one tone, modified only by light and shade; but the most heroic man among Christians is not a demigod: he is a being profoundly individual, tormented, combating, suffering, and who throughout his real life shares with environing Nature, and receives from every side the reflection of her colors. Sculpture, generalizing, raises itself to the dignity of allegory--painting, individualizing, descends to the familiarity of portraiture."