Most medieval and early modern philosophers took it for granted that the human soul has numerous faculties that enable it to produce a large variety of activities. Thus, thanks to the intellect it can produce acts of thinking, and thanks to the will it can bring about acts of willing. But what are the intellect, the will and other faculties? How are they related to the soul? Where are they located? And how can they be activated in a given situation?


The project examined these questions by looking at a large number of Aristotelian and anti-Aristotelian texts, ranging from the thirteenth to the seventeenth century. It pays particular attention to the metaphysical problems that were at stake, for theories of faculties were always part of general theories of the soul. While Aristotelian authors claimed that it was impossible to give an account of faculties without referring to souls as substantial forms, anti-Aristotelians rejected every appeal to forms. And while many Aristotelians thought that faculties could be described as real things acting inside a human being, anti-Aristotelians denied that there was a network of inner agents. Moreover, there was a controversy about the way faculties should be related to the body. Some philosophers claimed that all the faculties should be assigned to specific parts of the body, while others took some faculties – paradigmatically intellect and will – to be independent of the body. This gave rise to a heated debate about the materiality or immateriality of faculties.

Knowledge Transfer

The metaphysical controversies have been analyzed in a number of articles and in two books:

Klaus Corcilius and Dominik Perler (Eds.), Partitioning the Soul. Debates from Plato to Leibniz, Berlin, Boston: De Gruyter, 2014

Dominik Perler (Ed.), The Faculties: A History, Oxford – New York: Oxford University Press, 2015

The debate between materialists and immaterialists has been studied in a doctoral dissertation: (D-2-4-1) Immaterialität, Materialität, Intentionalität. Johannes Buridans Philosophie des Geistes (by Martin Klein, Phil. Diss. Humboldt-Universität 2016).

Many parts of the project have been presented at international conferences and workshops, among them “Continuity and Innovation in Medieval and Modern Philosophy” in London (October 2011), “A History of Faculties” in Berlin (July 2012), “Cognition in Medieval and Early Modern Philosophy” in Princeton (February 2013), “Thinking in the Middle Ages” in Berlin (April 2014), “Metaphysical Themes in Medieval Philosophy” in Boulder (February 2015), “Error in Medieval Philosophy” in Cologne (September 2016). Dominik Perler gave seminars on topics related to the research project when he was Global Scholar at Princeton University (2013-15) and Chaim Perelman Professor at the Université libre de Bruxelles (2016).

A number of collaborative projects and networks for graduate students have been established, among them with the Universities of Toronto and Groningen (regular workshops since 2011) and Princeton University (since 2013). Helen Hattab (University of Houston) participated as a Topoi Fellow in the activities of the research project (2015).