c. 1175-1253

English Physicist and Philosopher

Though he is perhaps best known as the teacher of Roger Bacon (1213-1292), Robert Grosseteste distinguished himself as a scientist in his own right. He wrote on astronomy, discussing comets and advancing a theory of tides. He also presented his own theories concerning light and sound. He described light as the basic substance of the universe and postulated, with considerable accuracy, that sound was a vibrating motion passing through the air.

Grosseteste was born the son of poor parents, and at an early age was forced to earn his own living, at times resorting to begging. The mayor of his hometown, Lincoln, England, eventually recognized his intellectual abilities, and arranged to have him enrolled in school. There he distinguished himself so much that he went on to an academic career that took him successively to the universities of Oxford, Cambridge...