Copernicus and Orbes

Abstract

The author tries to demonstrate that Copernicus’ understanding of orbes is identical to that of late medieval and renaissance tradition, according to which orbes are real, material spheres (orbs) or spherical shells. The first part of the article describes the basic concepts of the so called Aristotelian-Ptolemaic compromise as presented by Roger Bacon and Pierre d’Ailly in the cosmological tradition, and by Peurbach in the astronomical tradition. The second part illuminates those elements from the book On the Revolutions of Heavenly Spheres which in author’s opinion undoubtedly show that Copernicus’ thought is framed by a traditional conceptual apparatus of real spheres. The author concludes that it is only reality or materiality that can be attributed to the Copernicus’ heavenly spheres. The interpretations that credit Copernicus with the concept of hard, rigid spheres wrongly attributes to him the concept that emerged after Copernicus.