Abstract
The twelfth century has been characterized as an era of change, a cultural renaissance which saw the beginning of scholasticism, the rise of the universities, the introduction of new texts from the Graeco-Arabic philosophical tradition. It is this era, so it has been argued, that saw the birth of scientific reasoning. In this project we argue against this: scientific reasoning was already fully alive in the earlier Middle Ages. The instruments for a critical reflection on texts and a dialectical engagement with them were inherited from Late Antiquity, further developed and newly invented in the medieval period to serve new purposes. The evidence, however, has not been properly acknowledged by modern scholarship, because it took the shape of 'paratexts' rather than texts: annotations, glosses and diagrams written in the margins and on the flyleaves and empty spaces of books. These paratexts were, generally, not included in scholarly critical editions. Now that hundreds of manuscript collections are available online we can finally see this hidden material, and analyse its importance for the history of thinking. Exploring a core body of texts and following the paths of leading medieval scholars, we will reassess the continuities and changes in the techniques of scientific argumentation for the long Middle Ages through the lens of this marginal material. Thus we aim at a new understanding of the historical roots of a fundamental instrument in our own academic world: the dialectical method of reasoning, which still serves as the main scientific model in Western culture.