"The book which the reader now holds in his hands, from one end to the other, as a whole and in its details, whatever gaps, exceptions, or weaknesses it may contain, treats of the advance from evil to good, from injustice to justice, from falsity to truth, from darkness to daylight, from blind appetite to conscience, from decay to life, from bestiality to duty, from Hell to Heaven, from limbo to God. Matter itself is the starting-point, and the point of arrival is the soul. Hydra at the beginning, an angel at the end."