This is the first paper in a series in which we provide critical editions of four texts written between the eleventh and the thirteenth century concerning Proposition III.5 of Menelaus' Spherics. The first paper contains introductory material on the work of Ibn ʿIrāq on spherical geometry and a critical edition of his two texts on the rectification of Proposition III.5, together with translations and historical and mathematical commentaries. The second paper contains critical editions of the texts by Naṣīr al-Dīn al-Ṭūsī and Ibn Abī Jarrāda on the same subject, again with translations and historical and mathematical commentaries.

The article considers a brief catechistic presentation of a Galenic medical doctrine, the critical days, by the 9th century translator and thinker, Qusṭā ibn Lūqā (d. 912/3), found in a manuscript in Iran. The piece is first shown to have been derived from Galen's treatise on the critical days. Then, it is discussed section by section, in commentary form, to elucidate the medical doctrines Qusṭā propounds. Lastly, the piece is compared with an earlier attempt, by al-Kindī (d. c. 870), to describe the critical days mathematically. The various medical doctrines behind the treatise are discussed, as are the varying approaches to scientific method. The article concludes with contrasting the a priori mathematical scientific method of al-Kindī with the a posteriori empirical method of Galen/Qusṭā, and offers suggestions about the chronologies of the appearances of these doctrines and texts in Arabic. A transcription of the Arabic text is appended.

As is well known, taṣawwur and taṣdīq, conceptualization and assent, are essential notions in the epistemology of Arabo-Islamic philosophy. Conceptualization amounts to the definition of an object of knowledge, and assent to the recognition, via some kind of reasoning, that this definition is true. One of the authors who dealt with both topics in greatest depth was al-Fārābī, whose oeuvre exerted a profound influence on Ibn Bājja. This article analyzes the materials on taṣawwur and taṣdīq found in Ibn Bājja's notes regarding al-Fārābī's writings on logic and scientific method, namely the glosses to Kitāb al-Burhān. The analysis shows, on the one hand, that he understood perfectly the importance of both terms in al-Fārābī's construal of Aristotle's scientific method; and on the other, that he used them to deal with human thought processes. Indeed, conceptualization and assent were essential notions for Ibn Bājja, and underlie some of his best-known works.

Avicenna came to an unexpected conclusion in the treatise On Plants in al-Šifāʾ: that plants are not alive. This judgment is surprising in view of Aristotle's opinion that that which has a soul is alive. This paper shows that there is a development in Avicenna's thought on plants' life. He begins with the Aristotelian view that plants are alive inasmuch as they possess a soul, as we see in his early A Compendium on the Soul. Later, however, through his investigation of the faculties of the soul, discussed mainly in the first part of the Canon of Medicine, he is led to conclude that plants could not be said to be alive. This paper indicates the importance of considering the influence of Avicenna's medical findings on his philosophical arguments when examining the development of his thought.

Since the beginning of mankind, man has been concerned with the conservation of food in order to prolong its edibility. Over time, different food preservation methods have been discovered and improved, and there are many works that describe these techniques. This work will describe the knowledge and the development of preservation techniques of inhabitants of the Iberian Peninsula. The work focuses on the various achievements from the first to the sixteenth centuries, allowing us to appreciate the different historic contributions. The selected and consulted works are: L.J.M. Columela, Los doce libros de Agricultura (The Twelve Books of Agriculture), Abū al-Jayr, Kitāb al-Filāḥa. Tratado de agricultura (Book of Agriculture), Ibn Baṣṣāl, Kitāb al-Filāḥa. Libro de agricultura (Book of Agriculture), Ibn al-ʿAwwām, Kitāb al-Filāḥa. Libro de Agricultura (Book of Agriculture), Ibn Luyūn, Kitāb al-Filāḥa. Tratado de Agricultura (Book of Agriculture), Alonso de Herrera, Agricultura general (General Agriculture).

The aim of this article is to present a medieval Arabic report regarding six animals from the Gulf of Aden, to provide a zoological identification of five of the animals in question, which may be identified, and to comment on the biological data provided by the report in the light of both contemporary and modern zoological knowledge and, thus, to evaluate the scientific standard of the report.