Visual and Verbal Commentaries in the European Renaissance: Erasmus Reinhold’s Treatment of Classical Sources on Astronomy

Immediately following the publication of Copernicus's major work, De revolutionibus orbium coelestium (Nuremberg, 1543), the renowned Renaissance astronomer Erasmus Reinhold of Saalfeld (1511-1553) issued a Greek-and-Latin edition of the first book of Ptolemy's Almagest with commentaries. It was entitled Ptolemaei Mathematicae constructionis liber primus (Wittenberg, in 1549). Employing images and textual commentaries, Reinhold aimed to make Ptolemy's work accessible to his students at the University of Wittenberg. The commentary strengthened fundamental cosmological arguments presented in the first book of the Almagest, especially the central position of the Earth in the cosmos and its immobility. The Reinhold edition documents Renaissance commentary practices and their dynamic and transformative character. It is argued that the publication of Copernicus's heliocentric theory motivated astronomy professors such as Reinhold to reassess Ptolemy's cosmological arguments and analyze them with renewed interest.