O Roma nobilis orbis et domina (O noble Rome, mistress of the world), as the anonymous poet from Verona in the late ninth or early tenth century put it. The next Ordered Universe symposium starts today, in the eternal city, bi-located at the University of Notre Dame du Lac, Rome Global Gateway and Università di Roma, Tor Vergata. A packed programme to explore Grosseteste’s evocation and examination of the universe. The De sphera, composed in about 1215 forms the bulk of the collaborative reading sessions, in which treatise he expounds the sphericity of the world-machine, using creatively Platonic and Aristotelian conceptions of the cosmos, wrapped up in Genesis, the mathematical astronomy of Ptolemy, a range of Arabic astronomical authorities, Thebit, Alfraganus (in their Latin guises) and the anonymous author of the Theorica planetarum, and the contemporaneous work by the Englishman John Sacrobosco (or John Hollywood as we might say). Moving from the form and disposition of the universe, to planetary astronomy, Grosseteste’s treatise provides a physical account of the cosmos, built over geometrical mathematics, and raises some complex questions over precession, trepidation and parallax. The intricacies of these questions and their resolution, or not, we will look forward to delving into.
The astronomical accounts are connected closely to the medieval science of time-reckoning, on which Grosseteste was also a noted authority. A half-day conference on Wednesday will feature Neil Lewis, Anne Lawrence Mathers, Philipp Nothaft and Richard Bower on various wider and deeper aspects of questions of time and its measurement in the Middle Ages and from the perspective of modern cosmology. And then the symposium turns to the instantiation of Grosseteste’s De sphera in the Compotus correctorius, his great, and lasting, contribution to time-calculation, including the vital dating of Easter, the moveable feast at the centre of Christian life and ritual practice. Holding the two treatises against each other is an excellent reminder of some of the broader purposes for learning in the Middle Ages. The movements of the heavenly bodies and reflection on the cosmos had at its root a visceral connection with the creation of the Christian universe, and the moment at which it was restored in the death and resurrection of Christ. Temporality and eternity, space and time, daily human life and the perfect motion of the spheres all cohere and intersect at this moment. The public lectures on Thursday at 18.00, on medieval and modern planetary knowledge unfold the wider implications of Grosseteste’s subjects and the enduring human fascination with the place of humanity within the vastness of space, from our neighbouring planets to the universe as a whole.
The treatises show many of Grosseteste’s characteristic habits, a bold encounter between authoritative sources, including some puzzlement at areas where their theoretical positions appear not to be in concord with each other, or with physical realities. The same urgency that is to found in other treatises in probing and synthesising these sources, and a similar breadth of learning and experience, are evident in both treatises under scrutiny. Grosseteste’s breadth of vision and his capacity to relate ideas to each are in full flow, between the individual and the general, the cosmological and the anthropological, the paradeigmatic and eschatological and the present human condition, fallen, partial, but still redeemable and redeemed.