Alexander of Hales (also Halensis, Alensis, Halesius, Alesius ; 21 August 1245), also called Doctor Irrefragibilis (by Pope Alexander IV in the Bull De Fontibus Paradisi) and Theologorum Monarcha, was a Franciscan friar, theologian and philosopher important in the development of scholasticism. Life Alexander was born at Hales, Shropshire (today Halesowen, West Midlands), England, between 1180 and 1186. He came from a rather wealthy country family. He studied at the University of Paris and became a master of arts sometime before 1210. He began to read theology in 1212 or 1213, and became a regent master in 1220 or 1221. He introduced the Sentences of Peter Lombard as the basic textbook for the study of theology. During the University strike of 1229, Alexander participated in an embassy to Rome to discuss the place of Aristotle in the curriculum. Having held a prebend at Holborn (prior to 1229) and a canonry of St. Paul's in London (1226-1229), he visited England in 1230 and received a canonry and an archdeaconry in Coventry and Lichfield, his native diocese. He taught at Paris in the academic year 1232–33, but was appointed to a delegation by Henry III of England in 1235, along with Simon Langton and Fulk Basset, to negotiate the renewal of the peace between England and France. In 1236 or 1237, aged about 50, Alexander entered the Franciscan Order, having previously considered both the Cistercians and the Dominicans. He thus became the first Franciscan friar to hold a University chair. His doctrinal positions became the starting point of the Franciscan school of theology. He continued to teach and to represent the University, and participated in the First Council of Lyon in the winter of 1245. After returning to Paris, Alexander fell ill, probably due to an epidemic then sweeping the city. Shortly before his death, he passed his chair on to John of La Rochelle, setting the precedent for that chair to be held by a Franciscan. Alexander died at Paris on 21 August 1245. As the first Franciscan to hold a chair at the University of Paris, Alexander had many significant disciples. He was called Doctor Irrefragibilis (Irrefutable Teacher) and Doctor Doctorum (Teacher of Teachers). The latter title is especially suggestive of his role in forming several Franciscans who later became influential thinkers in the faculty, among them Bonaventure, John of La Rochelle, Odo Rigaldus, William of Middleton and Richard Rufus