Where Did Copernicus Obtain the Tools to Build His Heliocentric Model? Historical Considerations and a Guiding Translation of Valentin Rose's "Ptolemaeus und die Schule von Toledo" (1874)

Abstract

We present a translation of the German text of an 1874 article by Valentin Rose that concerns the possible school of translators that worked in Toledo, Spain, from about 1150 to 1250. Rose's article relies significantly on the first-hand account of the activities in Toledo by the Englishman Daniel of Morley. The most prolific translator in Toledo was Gerard of Cremona, who translated Ptolemy's Almagest from Arabic into Latin with the help of Galib the Mozarab; this translation was significant to Copernicus's work. Georg Peurbach and Regiomontanus based their Epitome of the Almagest (1463) on Gerard's translation, which in turn introduced Greek astronomy to astronomers in Italy and throughout Europe. Copernicus studied in Padua in the first few years of the sixteenth century, where he learned about Ptolemy's Almagest. Copernicus's book De Revolutionibus (1543) also contains two geometrical tools of astronomers from thirteenth century Maragha, and his model of the motion of the Moon is mathematically identical to that of Ibn al-Shatir (fourteenth century Damascus). A Greek language manuscript written prior to 1308, and the residence in Padua of Moses Galeano, a Jewish scholar from Constantinople and Crete, who was familiar with the work of Ibn al-Shatir, provide evidence of the transmission of Arabic astronomical ideas to Copernicus. We have only begun to understand this conduit of transmission.