Since the work is intended for a circle of readers who cannot be assumed to have a previous acquaintance with the authorities who are cited here and there, it is necessary to indicate their several positions in advance. The chief sources of the story are the letters of Abélard and Heloise. The first letter of the series, entitled the ‘Story of my Calamities,’ is an autobiographical sketch, covering the first fifty years of Abélard’s life. To these must be added the letters of St. Bernard, abbot of Clairvaux: of Peter the Venerable, abbot of Cluny: of Jean Roscelin, canon of Compiègne, Abélard’s early teacher: and of Fulques of Deuil, a contemporary monk. A number of Latin works written shortly after Abélard’s death complete, or complicate, the narrative. The principal of these are: the _Vita Beati Bernardi_, written by his monk-secretary: the _Vita Beati Goswini_, by two monks of the period: the _De gestis Frederici I._ of a Cistercian bishop, Otto of Freising: the _Metalogicus_ and the _Historia Pontificalis_ of John of Salisbury: and the _Vita Ludovici Grossi_ and _De rebus a se gestis_ of Suger, abbot of St. Denis, and first royal councillor. Many of the chronicles of the twelfth century also contain brief references. Chief amongst the later French historians is Du Boulai with his _Historia Universitatis Parisiensis_—‘the most stupid man who ever wrote a valuable book,’ says Mr. R. L. Poole. Amongst other French chroniclers of the sixteenth and seventeenth centuries we may mention: De Launoy (_De scholis celebrioribus_), Dubois (_Historia Ecclesiæ Parisiensis_), Lobineau (_Histoire de Bretagne_), Félibien (_Histoire de l’abbaye de Saint Denys_ and _Histoire de la ville de Paris_), Longueval (_Histoire de l’Église Gallicane_), Tarbé (_Recherches historiques sur la ville de Sens_), and, of course, the _Histoire littéraire de la France_, _Gallia Christiana_, and ecclesiastical historians generally.