יום ב' 04.05.2009 , 18:00 - 20:00
חדר 449 בנין גילמן

Professor Dominik Perler,
Humboldt University, Berlin
Silverman Guest Professor, The Cohn Institute

A Radical Doubt: The Emergence of Skepticism in Medieval Thought

Since the time of Descartes, who introduced the hypothesis of a malicious demon into philosophical debates, skepticism has become one of the central problems of epistemology. It seems insufficient to explain how we acquire knowledge. We first need to refute radical skeptical hypotheses, thus showing that we can have knowledge at all. But why has skepticism become a serious problem? And why do many philosophers conceive of knowledge as a relation between an “inner” world of thoughts and an “outer” world of material objects – a relation that can always be manipulated by a powerful demon?

In my presentation I intend to show that this type of skepticism is not a natural philosophical problem that inevitably arises in every context. It is rather the outcome of a certain epistemological theory that opens a radical gap between an inner and an outer world. This gap is not to be found in ancient skepticism, nor is it just the invention of Descartes. A number of transformations in late medieval philosophy and theology led to the creation of this gap. In particular, two theoretical shifts were responsible for the emergence of radical doubts: (a) a shift from a model that takes the human mind to be a cognitive faculty “assimilating” objects in the world and becoming somehow identical to them, to a model that conceives of it as the place of inner representations, (b) a shift from a theory that takes God to be the last guarantee for successful cognition, to a theory that presents him as an absolutely free and omnipotent being, unlimited in his power and able to intervene in every cognitive process. In my paper I will focus on these two shifts, arguing that the opposition between an “inner” and an “outer” world is not simply given but was created within a certain theoretical framework. My argument will be based on an analysis of texts by Thomas Aquinas, Peter John Olivi, William Crathorn and René Descartes.