 Epistles 7 and 8 explicitly recall the Aristotelian division of the theoretical and practical sciences. Epistle 7 is extensively based on Aristotle (when the Ikhwân introduce the nine “philosophical questions,” they are thinking of the Aristotelian categories, cf. I, 262, 14–266, 7; Epistle 29, III, 35, 6–7; Epistle 40, III, 345, 6–346, 6; Epistle 42, III, 513, 14–16 and 514, 13–516, 5). However, the ultimate goal of the scientific investigation is identified with the path towards hereafter and even connected to asceticism where scientists and prophets follow the same way: Aristotelian science is linked to the Isma‘ili teaching (ta‘lîm, cf. I, 274, 20–275, 4). The “programmatic” aim of Epistle 7 leads us to consider it as the ideal introduction to the whole corpus. On the other hand, the authors' Ismâ‘îli commitment is proven by the fact that in the complementary treatise On the practical arts the ancient “banausic” (utilitarian) activities are dealt with which were held in high esteem in Ismâ‘îlism (cf. Lewis 1943; Marquet 1961; and, more recently, Yasien 2006 and Daftary 2007, 115).