He studied at the University of Paris, gaining a Master of Theology. He joined the Dominican order at a young age. Dietrich was a prolific writer. His writings include compositions on nearly every branch of theology, philosophy, and natural science known to his period.
In his treatise De iride et de radialibus impressionibus, Theodoric gave an interpretation of the rainbow as a result of refraction of light in its spectrum of colours, even though he was not actually a scientist, nor in particular an experimentalist, and as a consequence he did not master the experimental method; nevertheless, he showed an attitude to research with a properly scientific object.
Both Theodoric and Descartes showed that the rainbow is made up of rays that enter a droplet and are reflected once from the inner surface. Theodoric of Freiberg also wrote works on theology, philosophy, optics, and astronomy.
A brief biography of Theodoric of Freiberg
