Complexio, Enunciatio, Assensus: The Role of Propositions in Knowledge according to John Buridan

This paper is an attempt to rethink from two perspectives Buridan’s ideas concerning knowledge: On the one hand, I explore Buridan’s theory of knowledge in the hope that it will shed some light on the intuition that the structure of propositions determines the justification of our beliefs on various different levels. On the other hand, I would like to contribute to demonstrating the consistency of Buridan’s thought,which has been remarked by almost all scholars working on Buridan: in particular, I am interested in exploring the benefits of using supposition theory when applied to the theory of knowledge. I will start by examining Buridan’s conception of scientia (as opposed to error, opinio and fides), from the perspective of two distinctions which are very important to Buridan’s theory of the proposition: complexio/enunciatio and enunciatio/assensus. Then I will recall Buridan’s analysis of propositions (and his use of supposition to define truth conditions) to show their consistency with this conception of knowledge.