[The visual process as a theological analog of Roger Bacon's eye anatomy and physiology]

The author presents Roger Bacon's conception of the anatomy and physiology of the human eye. The knowledge of ocular function is a precondition to understand the laws of the "perspectiva", the science of seeing. But Bacon doesn't stress perspective per se. The physical laws of light, which are to be analysed in geometrical forms, are analogous to those of the infusion of divine grace. Optics (in the Middle Ages synonymous with perspective) seemed to be the model by which God spread his grace to the world. To understand the physical laws of optics meant that one might gain insight into the nature of God.