Emanuele Rovati

The Centiloquium is a collection of one hundred astrological aphorisms falsely attributed to Claudius Ptolemy and usually circulating with a commentary by the 10th c. Egyptian polymath Abū Jaʿfar Aḥmad ibn Yūsuf ibn al-Dāya. The base-text and its commentary entered Europe via multiple 12th c. translations from Arabic and quickly rose to prominence in the Latin tradition, as shown by the fact that they rank second in the list of the most widespread Latin treatises on astrology. Their influence was not confined to the domain of astrology, as shown by quotations in the works of Albert the Great, Thomas of Aquinas, Roger Bacon and other major figures of intellectual history.

The first part of the PhD project aims to provide a critical edition and English translation of the most widespread Latin version of the Centiloquium and its commentary, which was prepared by Plato of Tivoli in 1136 and is extant in more than a hundred manuscripts. Stemmatological algorithms will be resorted to in order to cope with the work’s intricate textual transmission.

Building on the critical edition, the second part of the project aims to determine the Centiloquium’s impact on Western intellectual history. To this end, a considerable number of 12th-13th c. astrological, philosophical and medical writings influenced by the Centiloquium shall be scrutinised. The investigation shall focus on topics such as discussions of epistemology and foreknowledge, the nature of comets, the theoretical and practical frameworks of medical astrology, the working of talismans and the rectification of birth charts.

The PhD project is funded by the Swiss National Science Foundation (funding scheme Doc.CH, grant number 203856) and carried out in collaboration with the project Ptolemaeus Arabus et Latinus of the Bavarian Academy of Sciences and Humanities in Munich.