 Possibly as a consequence of the diffusion of the above works, the influence of the Brethren of Purity seems to have spread among a number of Jewish philosophers working in Spain during the 13th century. In some cases, this influence passed through other minor Arab-Islamic authors, whose work was well-known among Spanish Jewish readers. The Spanish Islamic philosopher Ibn al-Sid al-Batalyawsi (from Badajoz, d. 1127) wrote a sort of compendium of the Brethren’s doctrines, the Book of the Gardens (Kitab al-hada’iq), which was widespread among Jewish authors (Kaufmann 1880, 32–63) either in its original Arabic text, or in its three Medieval Hebrew translations (written between 1200 and 1370: see Steinschneider 1893, 286–288; Richler 1977), often under the title Book of Intellectual Circles (Sefer ha-‘agullot ha-re‘yoniyyot); it was one of the direct sources of a Spanish philosopher and kabbalist, Isaac Ibn Latif, who spoke about the Brethren’s doctrine of the five degrees of soul (vegetal, animal, human, sapiential, prophetical) in his Hebrew book The Gate of Heavens (Sha‘ar ha-shamayim), written in the period 1230–1250 (see Heller-Wilensky 1967, 199). Another anonymous work, The Balance of Speculations (Me’ozney ha-‘iyyunim), written in Hebrew (or in a Judaeo-Arabic lost original version) in 13th-century Spain, is full of passages about numerology, cosmology, theology and natural sciences: some of them might have been inspired by al-Batalyawsi’s compendium, but some others were evidently taken from the Epistle of the Brethren of Purity, in particular those concerning the essence of faith, mineralogy and botany (Abrahamov 1995). Finally, it should be noted that the Brethren of Purity were employed as a direct philosophical source by Shem Tov Ibn Falaquera in a number of occasions. In his Neoplatonic philosophical anthology, The Book of Degrees (Sefer ha-ma‘alot), a Hebrew quotation ascribed to a “sage” (did Falaquera know that the work was made by al-Majriti?) is in reality a literal passage of the Epistle of the Brethren of Purity dealing with the relationship between the Universal Soul and the particular souls. Falaquera’s The Book of the Seeker (Sefer ha-Mevaqqesh), a sort of short popular encyclopedia written in 1263, is full of quotations from most of the Brethren’s treatises: these quotations deal with several themes, like the difference between science and faith, some mathematical questions, the principles of astronomy and music, the meaning of the term “nature”, the doctrine of anima mundi, the climates, as well as some doctrines about logic, meteorology, music (about this point, see Shiloah 1968), astrology and natural sciences, and even some moral tales. Also the Brethren’s scientific doctrines exerted a considerable influence over 13th-century Jewish authors. In books three and four of his bulky scientific-philosophical encyclopedia, The Opinions of the Philosophers (De‘ot ha-filosofim), written around 1270 and still unpublished, Falaquera quotes a number of passages of the Brethren concerning mineralogy and botany, where a sort of mixture of Aristotelian doctrines and alchemy can be found. Falaquera’s mineralogical doctrines should have directly influenced the treatment of mineralogy in other Hebrew texts, written around 1300, in particular in Gershom ben Solomon of Arles’ The Gate of Heavens and in an alchemical treatise falsely ascribed to an Arabic author. Finally, the zoology and the mathematics of the Brethren of Purity were employed by Qalonymos ben Qalonymos for writing down his own Hebrew books on morals (Epistle On Animals, Iggeret ba‘aley hayyim) and on mathematics (Book of Kings, Sefer ha-melakim: see Lévy 1996, 69).