SIMPLICIUS ON THE FILLING OF SPACE, IN CAELO 655.9–656.5: A DELIBERATE MISTAKE?

In In cael. 655.9–656.5 Simplicius reports an argument in which an apparent justification is offered for the false claim by Aristotle that ‘pyramids’ (regular tetrahedra) can completely fill space. This argument was analysed by Ian Mueller in an Appendix to his translation of In caelo, and the outline of an alternative has been presented in Myrto Hatzimichali's study of Potamo of Alexandria. In this article I contest Mueller's interpretation, and expand on the one reported by Hatzimichali. I also contest Mueller's claim that a version of his interpretation can be found in the partial commentary by Peter of Auvergne. It is suggested here that the ‘justification’ reported by Simplicius is a deliberate slip in logic, which is accompanied by a carefully constructed cover-up involving some quite tricky geometry. Simplicius makes frequent reference to Alexander of Aphrodisias, but it is argued here that he has been very selective with these citations.