The earliest debate on the argument from ignorance emerged in Islamic rational theology around the fourth/tenth century, approximately seven centuries before John Locke identified it as a distinct type of argument. The most influential defences of the epistemological principle that ‘that for which there is no evidence must be negated’ are encountered in Muʿtazilī sources, particularly ʿAbd al-Jabbār and al-Malāḥimī who argue that without this principle scepticism will follow. The principle was defended on different grounds by some earlier Ashʿarīs, but was then rejected by al-Juwaynī, and was eventually classed as a fallacy by Fakhr al-Dīn al-Rāzī whose Nihāyat al-ʿuqūl contains the most definitive and comprehensive refutation of classical kalām epistemology and the first ever defence of Aristotelian logic in a kalām summa. According to the eighth/fourteenth-century historian Ibn Khaldūn, this debate provided the main impetus for the philosophical turn that Ashʿarism took during the sixth/twelfth century.

The Andalusian mathematician and astronomer Ibn Muʿāḏ al-Jayyānī (11th century) is the author of an important commentary on the concept of ratio, in which he attempts to justify the Euclidean definition of proportionality between magnitudes – the celebrated Definition V.5 – and that of greater ratio. In addition to an analysis of the commentary, we provide a French translation and a critical edition of the original Arabic text. We also attempted to settle some problems linked to the biography of Ibn Muʿāḏ.

Philosophical and medical excellence notwithstanding, Avicenna was far from being an otherwordly person who buried himself in his books. He had an extraordinarily adventurous life and is reported to have been fond of good food, drink, and lovemaking. This article discusses the wellknown but quite unusual view that he died of having too much sex. A detailed analysis of the sources and a common-sense approach to some of their medical claims will show that this allegation is not supported by any evidence whatsoever. Quite the opposite: it will be argued that the main source on which all later reports must taken to depend has been tampered with in two places to produce the image that we know. Thus, we must assume that people hostile to Avicenna and his philosophy are behind this, their forgery most likely having been committed in the first half of the twelfth century AD.

Ibn al-Faḍl al-Anṭākī's Kitāb Bahjat al-muʾmin, the Book of the Delight of the Believer preserves, in the first part, in at least three of its 100 philosophical and theological problems, passages from the hitherto lost Arabic version of Philoponus' De Aeternitate mundi contra Proclum. All quotations are taken from the refutation of the first proof, one of them from the beginning which is also lost in Greek. For this latter passage a parallel is found in al-Isfizārī who draws on the same Philoponus source in his Kitāb fī Masāʾil al-umūr al-ilāhiyya (Book on Metaphysical Questions). A comparison of the other passages to the extant Greek text suggests that al-Anṭākī quotes Philoponus faithfully, but with some omissions and occasional re-arrangement of his source. Additional evidence for al-Anṭākī's overall accurate use of sources can be gained from his quotations of the extant Arabic versions of the De Anima-paraphrase, Nemesius' De Natura hominis and ʿAlī b. Rabban al-Ṭabarī's Firdaws al-ḥikma (Paradise of Wisdom).

The volume D'al-Khwārizmī à Descartes is a monumental contribution to the world history of mathematical sciences, showing clearly that Arabic mathematics was an indispensable predecessor of early modern European mathematics. Roshdi Rashed is known, first of all, as an editor of classical mathematical writings in Arabic by such authors as al-Khwārizmī, Thābit ibn Qurra, Ibrāhīm ibn Sinān, Ibn al-Haytham, al-Khayyām, Sharaf al-Dīn al-Ṭūsī, as well as of the Arabic versions of Apollonius' Conics, Diophantus' Arithmetica, and Diocles' Burning Mirrors. As the volume under review shows, he is also a historian of mathematics of the first class who has transformed historiography. This book is, in a sense, a manifesto of Prof. Rashed's entire œuvre.