Dietrich of Freiberg’s Theory of Perfectional Forms

This article investigates the philosophical elaboration of the concept of “perfectional form” (forma perfectionalis) in Dietrich of Freiberg’s works. Although Dietrich draws on the traditional notion of perfection to a certain extent, it appears that in his view, what he calls perfectional forms represent a special type of form distinct from the classical division between substantial and accidental forms. The main part of the article analyzes the different uses of this concept made by Dietrich, from his theory of light to his views on the essence of the intellect. The final part of this study aims to evaluate the influence of Dietrich’s theory on the so-called German Dominican school. It is argued that, while Dietrich’s influence on Nicholas of Strasbourg is possible but cannot be firmly established, his theory was explicitly taken up and extended to a more metaphysical dimension by Berthold of Moosburg.