Adelard of Bath and Roger Bacon: early English natural philosophers and scientists.

The image of Roger Bacon as a 'modern' experimental scientist was propagated as historical truth in 19th century scientific historiography. Twentieth century criticisms attacked this tradition, arguing that Bacon was primarily a medieval philosopher with 'medieval' scientific interests. However, recent scholarship has provided a more careful and critical account of Bacon's science, and identifies his greatest achievement in terms of his successful attempt to assimilate the worlds of Greek and Islamic optics. It can be justly claimed that Roger Bacon was the first Western thinker in the middle ages to have mastered most of the Greek sources and the central Islamic source in optics. He made this scientific domain understandable for a Western Latin-reading audience. Yet, Bacon himself acknowledged Adelard of Bath, whose translations and commentary of Euclid's Elements set the foundations for a science of optics, as the true pioneer.