A rebuttal of recent arguments for Maragha influence on Copernicus

I reply to recent arguments by Peter Barker & Tofigh Heidarzadeh, Arun Bala, and F. Jamil Ragep claiming that certain aspects Copernicus’s astronomical models where influenced by late Islamic authors connected with the Maragha school. In particular, I argue that: the deleted passage in De revolutionibus that allegedly references unspecified previous authors on the Tusi couple actually refers to a simple harmonic motion, and not the Tusi couple; the arguments based on lettering and other conventions used in Copernicus’s figure for the Tusi couple have no evidentiary merit whatever; alleged indications that Nicole Oresme was aware of the Tusi couple are much more naturally explained on other grounds; plausibility considerations regarding the status of Arabic astronomy and norms regarding novelty claims weight against the influence thesis, not for it.

A Reluctant Innovator: Graeco-Arabic Astronomy in the Computus of Magister Cunestabulus (1175)

This article is dedicated to the obscure Computus of Magister Cunestabulus (England, 1175), which offers a unique spotlight on the way the twelfth-century ‘Renaissance’ in mathematical astronomy impacted the Latin computistical tradition. Armed with an unusually broad array of sources newly translated from Arabic, among them Ptolemy’s Almagest, Cunestabulus applied his advanced knowledge in the service of traditional Latin learning and established Church doctrine, defending the non-existence of Antipodeans in the southern hemisphere as well as the astronomical foundations of the ecclesiastical computus. His intricate explanation of the error underlying the Julian calendar, which was based on the Arabic theory of the ‘access and recess of the eighth sphere’, makes for a technically sophisticated and conceptually intriguing case of Graeco-Arabic science being used for apologetic ends in twelfth-century Latin writing.

Evolution of Arabic Astronomy in Relation with the Translation Movement in the Early Abbasid Era

In this work, the emergence of the Arabic astronomy in the early Abbasid era will be presented as an amalgam of various traditions. For this to be illustrated, a close analysis of the development of the cultural and political aspects in the Middle East will be presented that eventually allowed for the so-called Arabic or Islamic culture to flourish. The translation movement will be discussed briefly in order for various aspects of this period to be shown, emphasizing the duality of tradition and innovation. These aspects will be followed more closely in the field of astronomy, illustrating the various tendencies especially in the case of incorporation of Greek Uranography, and the relation between the Lunar Mansions and the Anwa. Political, religious and cultural changes left their traces on the accepted Academic tendencies of the period. For a better understanding the astronomical view at the dawn of the Abbasid era, a close look on the work of Ibn Qutaiba will take place, depicting the transitional period in which he lived.