Free The Friar and the Cipher by Lawrence Goldstone Page B

himself, he had agreed to lecture to them, which provided an enormous boost in the prestige of the order at the university. Adam Marsh, a Grosseteste protégé and one of Roger Bacon's future teachers, a man who would become extremely influential in English politics, joined the Franciscans because of Grosseteste.
    For all the political and ecclesiastic power he wielded, however, Robert Grosseteste's real legacy lay in his contribution to the advancement of science. “Master Robert, called Grosse-Teste, lately bishop of Lincoln, alone knew the sciences,” Roger Bacon would later write, and:
    For very illustrious men have been found, like Bishop Robert of Lincoln . . . who by the power of mathematics have learned to explain the causes of all things . . . Moreover, the sure proof of this matter is found in the writings of those men, as, for example, on impressions such as the rainbow, comets, generation of heat, investigation of localities on the earth and other matters, of which both theology and philosophy make use.
    Because of Grosseteste and Adam Marsh, Oxford became the center of scientific inquiry in northern Europe, and by association the order of itinerant, illiterate beggars envisioned by St. Francis became identified with the most forward-thinking intellectuals of the age.
    Grosseteste himself was the junction from which all experimental science grew. He divided scientific inquiry into three levels, based on the degree of certainty with which a person could trust his findings. At the bottom was that which could be known with surety: mathematics, for example. That a triangle was a three-sided, closed figure was an objective truth. The next level Grosseteste called natural physics, which today would incorporate a broad range of natural sciences, including botany, zoology, astronomy, optics, and chemistry. Conclusions in natural physics could be drawn with some degree of certainty through intense observation, although an experiment must yield the same result after many different trials in order to allow the experimenter to hypothesize a conclusion. A sufficient number of such conclusions would eventually yield the presence of a natural law. The highest level was what the thirteenth century called metaphysics, which was the science of God and the soul. Scholars, Grosseteste said, could not prove truth in the realm of metaphysics with any degree of certainty—the study of God required divine inspiration.
    Grosseteste employed a surprisingly modern form of scientific method. He carefully observed and applied mathematics to natural phenomena such as refracted light, the movement of heavenly bodies, thunder, the nature of clouds, or the physiology of horned animals, then deduced what he called a “definition” but what today would be called a theory. However, although he asserted the necessity of empirical verification, Grosseteste was not himself an experimenter.
    When Roger Bacon enrolled at Oxford, he encountered this new dedication to science and mathematics. It is not clear whether he arrived early enough to actually attend Grosseteste's lectures, but by 1228 Grosseteste's spirit, academic commitment, and willingness to go where knowledge took him permeated the school. Aristotle's physics and metaphysics were on the curriculum, and there were classes in geometry and optics. It was an exciting time to be a student—there was the sense of breaking through academic barriers and advancing knowledge on a larger stage. “Here [at Oxford], mainly owing to Grosseteste's influence, the
libri naturales
[Aristotle's work on natural science] were early accepted and never had to go underground,” noted the medieval historian Gordon Leff.
    The masters, particularly Adam Marsh, recognized Bacon's potential immediately and accepted him into their inner circle. Forty years later, the pride in Bacon's voice was unmistakable when he discussed his part in that great intellectual movement. Describing the science