c.1230-after 1275

A natural philosopher and optical scientist, Witelo probably studied arts at the University of Paris, and later canon law at Padua. During an Easter holiday (probably sometime between 1262 and 1265), he wrote Tractatus de primaria causa penitentie et de natura demonum, an astronomical work that plots the movement of the sun, the lunar cycle, and the variation of day and night. He later wrote a number of other works in natural philosophy. Only one, Perspectiva, survives, a huge tome on optics, rich with geometrical theory.