Medieval theology and natural philosophy influenced each other

A recent doctoral dissertation in philosophy of religion demonstrates that in the Middle Ages, theology and philosophy were in dynamic interaction with one another. This is apparent in debates on the psychology of the Incarnation.

Tuomas Vaura’s doctoral dissertation describes the academic debate on the psychology of the Incarnation during the 13th and early 14th centuries. Different conceptions of how Christ became human are at the core of these debates.

 “Mediaeval theologians were not afraid to ask questions and strove to answer them primarily through logic. On the other hand, they were also aware of the limits of human understanding,” Vaura explains.

Debates regarding the psychology of the Incarnation concerned the ability of Christ’s human aspect to know, desire and feel – his knowledge, will and passions.

 “It may seem strange for us to ask questions about how Christ felt about things, but mediaeval theologians did not find this odd at all. They would ask questions about the soul of Christ and didn’t hesitate in applying the latest psychological thinking of their time to answer them,” explains the doctoral candidate.

The dissertation approaches the mediaeval debate about God who became human from the perspective of philosophical psychology. In the Middle Ages, philosophical psychology was a branch of natural philosophy.

 “The theologians took concepts from the psychology that was a part of natural philosophy and applied them to theological debates. On the other hand, concepts developed in theology influenced the prevalent understanding of the soul in the natural sciences,” Vaura says.

Vaura has used contemporary sources to find indications of what kinds of feelings Christ experienced as a human, and how he was able to feel both joy and pain at the same time.

 “There was also academic debate about what kinds of human knowledge Christ possessed and whether he knew everything known by God while in human form. Theologians also debated what kinds of wills Christ had and how these different wills related to one another.”

Mediaeval theological and philosophical debate is still relevant

According to the doctoral candidate, the social impact of the study is apparent in the Evangelical Lutheran Church of today.

 “The research has themes which I hope will help the Church resolve its most acute challenges. For example, the Mediaeval debate on Christ’s conflicting wills could help the Church better understand how to find unity while encompassing many different views.”

These debates could also benefit the spiritual tradition of the Lutheran Church.

 “There is much talk in the Church about following Christ, but not so much about what kind of Christ we follow. A more comprehensive knowledge of Mediaeval theology could also help the Lutheran Church in its ecumenical relations with the Catholic Church,” Vaura points out.


ThM Tuomas Vaura will defend his doctoral dissertation entitled "The Psychology of the Incarnation in Thirteenth- and Early Fourteenth-Century Theology" on 3 November 2017 at 12.15 at the University of Helsinki’s Faculty of Theology. The public defence will take place in the University of Helsinki Main Building, Fabianinkatu 33, lecture hall 10.

The opponent will be Associate Professor Filipe Pereira da Silva, University of Helsinki, and the custos will be Sami Pihlström from the Faculty of Theology, University of Helsinki.

The dissertation is available in an electronic format through the E-thesis service.