The attitude of medieval men of letters towards plastic arts, architecture and applied art has so far been studied from a primarily aesthetic point of view. The cause of this may be found, I offer no opinion on it, in the conceptions of the authors who have been publishing on this during the last seventy-five years or in the fact that most medieval texts that until recently were available in editions, were for the greater part works of a theological, mystical or l encyclopaedic-theoretical kind. Anyhow, it is an estab- lished fact that these studies were brought to bear on the texts of a limited number of well-known medieval writers, such as: Augustine, Isidore of Sevilla, Strabo, Scotus Erigena, Alcuin, Hugh and Richard of S. Victor, Honore of Autun, Bonaventure, Thomas Aquinas and Vincent of Beauvais. The writings of these authors had been published in large series such as Migne's Patrologia Latina, the 3 1 L. Venturi, Storia della critica d'arte, Turin 1964 (1st ed. Brussels 1938); E. de Bruyne, Etudes d'Esthetique medievale, 3 vols, Bruges 1946; R. Assunto, La critica d'arte nel pensiero medioevale, Milan 1961; id., Die Theorie des SchOnen im Mittelalter, Cologne 1963; E. F. van der Grinten, Enquiries into the History of Art Historical Writing, Amsterdam 1952; L. Grassi, Costruzione della critica d'arte, Rome 1955; C. Barret, "Medieval Art Criticism", The British Journal of Aesthetics 5 (1965), 25-36; Encyclopedia of World Art, vol.