This volume [of Ikhwan al-Safaʾ (Brethren of Purity)] comprises the initial seven epistles on the natural sciences, which correspond to the corpus of Aristotle’s great works on the philosophy of nature, whilst also incorporating an Islamic interpretation of Neoplatonic ideas. Besides providing the necessary references to works by Aristotle and other Greek authors, this book deals with various doctrines of Ismaili origin echoed in the treatises, foremost of which is the hierarchical representation of the three natural kingdoms, reflected in the hierarchy of human beings.
The basis of human salvation is here seen in the relation between divine Artisan and human artisan, both of whom accomplish their works by actualising their knowledge. Although moral behaviour is a necessary condition, salvation cannot be reached without a thorough knowledge of the sciences described progressively in the Rasaʾil Ikhwan al-Safaʾ.