Vincent may have drawn from Hugo of St Victor the current doctrine that the arts have part in the work of man’s restoration; a doctrine abundantly justifying the presence of the sciences and crafts (composing the Mirror of Knowledge) in the sculpture and painting of the cathedral. There the Seven Liberal Arts are rendered, through allegorical figures; and the months of the year are symbolized in the Zodiac and the labours of the field which make up man’s annual toil. Philosophy is shown and Fortune’s wheel; the Virtues and Vices are represented in personifications, and even their conflict, the Psychomachia, may be shown. At last the Mirror of History is reached. This will teach in concrete examples what has been learned from the figures of the abstract Virtues and Vices. Its chief source is the Bible. Those Old Testament incidents were selected which for centuries had been interpreted as prefigurements of the life of Christ; and each was presented as a pendant to the Gospel scene which it typified. These make the chief subjects of the coloured glass of Chartres and Bourges and other cathedrals where the windows are preserved. Here may be seen the Passion of Christ, surrounded by scenes from the Old Testament typifying it; likewise His Resurrection and its ancient types; and other significant incidents in the life of the Saviour and His virgin mother.[93] The latter is typified by the burning bush, by the fleece of Gideon, by the rod of Aaron, even as in the hymns of Adam of Saint-Victor.[94] Besides these incidents, leading personages of the Old Testament are presented as prefigurative of Christ, as in the great series of statues of Melchizedek, Abraham, Moses, Samuel, David, on the north portal of Chartres; while the four greater and twelve minor prophets are shown as types of the four Evangelists and the twelve Apostles. Christ himself is depicted on a window at St. Denis, between the allegorical figures of the Ancient Law and the Gospel,--figures which are allied to those of the uncrowned and blinded Synagogue and the triumphant Church, so frequently seen together upon cathedrals. Everywhere the tendency to symbolize is strong. Parts of the Crucifixion scene are rendered symbolically, and many of the parables. That of the Good Samaritan constantly appears upon the windows, and is always designed so as to convey the allegorical teaching drawn from it in Honorius’s sermon.[95]