Nature, Souls, and Numbers: Remarks on a Medieval Gloss on Gundissalinus’s De processione mundi

Gundissalinus’s De processione mundi expounds a detailed description of the institution of the universe based on a fascinating range of Latin and Arabic sources. Realising a synthesis between Avicenna’s and Avicebron’s metaphysical positions, the universe depicted by Gundissalinus is grounded upon a delicate and yet intrinsically coherent web of interpretations of divergent philosophical perspectives. A rather problematic point of De processione mundi is the use Gundissalinus makes of the ratio numerorum. In particular, his use of numerical series—twice in the text—to demonstrate the completeness of the created universe appears to entail striking contradictions with what Gundissalinus claims in his treatise. My contribution addresses this “consistency problem” pointing out that the meaning of the two numerological series can be clarified through a curious gloss on the text attested by the entire manuscript tradition of De processione mundi.