Grosseteste Robert (c.1168–1253), English theologian who began life on the bottom rung of feudal society in Suffolk and became one of the most influential philosophers in pre-Reformation England. He studied at Oxford, becoming a master of arts between 1186 and 1189. Sometime after this period he joined the household of William de Vere, bishop of Hereford. Grosseteste may have been associated with the local cathedral school in Hereford, several of whose members were part of a relatively advanced scientific tradition. It was a center for the study of natural science and astrology as well as liberal arts and theology. If so, this would explain, at least in part, his lifelong interest in work in natural philosophy. Between 1209 and 1214 Grosseteste became a master of theology, probably in Paris. In 1221 he became the first chancellor of Oxford. From 1229 to 1235 he was secular lecturer in theology to the recently established Franciscan order at Oxford. It was during his tenure with the Franciscans that he studied Greek – an unusual endeavor for a medieval schoolman. He spent the last eighteen years of his life as bishop of Lincoln. As a university scholar, Grosseteste was an original thinker who used Aristotelian and Augustinian theses as points of departure. He believed, with Aristotle, that sense knowledge is the basis of all knowledge, and that the basis for sense knowledge is our discovery of the cause of what is experienced or revealed by experiment. He also believed, with Augustine, that light plays an important role in creation. Thus he maintained that God produced the world by first creating prime matter from which issued a point of light (lux), the first corporeal form or power, one of whose manifestations is visible light. The diffusion of this light resulted in extension or tridimensionality in the form of the nine concentric celestial spheres and the four terrestrial spheres of fire, air, water, and earth. According to Grosseteste, the diffusion of light takes place in accordance with laws of mathematical proportionality (geometry). Everything, therefore, is a manifestation of light, and mathematics is consequently indispensable to science and knowledge generally. The principles Grosseteste employs to support his views are presented in, e.g., his commentary on Aristotle’s Posterior Analytics, the De luce (‘Of Light’), and the De lineis, angulis et figuris (‘Of Lines, Angles, and Figures’). He worked in areas as seemingly disparate as optics and angelology.
Grosseteste was one of the first to take an interest in and introduce into the Oxford curriculum newly recovered Aristotelian texts – some of which he translated, along with Greek commentaries on them. His work and interest in natural philosophy, mathematics, the Bible, and languages profoundly influenced his younger contemporary, Roger Bacon, and the educational goals of the Franciscan order. It also helped to stimulate work in these areas during the fourteenth century.
See also COMMENTARIES ON ARISTOTL. G.S.