 The implementation of the first task, the treatment of all philosophy as a unified whole, though historically seemingly unachievable, was accomplished by Avicenna almost without effort. Aristotle himself stands at the very beginning of this process. He clearly had a conception of the unity of all philosophy, which could be systematically presented on the basis of the logical structure set forth in the Posterior Analytics (Barnes 1994, p. xii), while his classification of the sciences in Metaphysics E1 and K7 showed what the outline of such a systematic presentation would be. In the polyphony of philosophical voices and systems that followed his death in 322 BC and throughout the Hellenistic period (336–31 BC), his suggestions went mostly unheeded by the Peripatetics and were only followed, at the end of that period, by Andronicus of Rhodes if only for the purposes of the order in which he put Aristotle’s school treatises (his extant corpus) in his first edition of them. In subsequent centuries, when the polyphony subsided to just two voices, of the Platonists and the Aristotelians, which eventually had to be presented as one for political reasons (to counter the one “divine” voice of the rapidly Christianizing Roman empire, east and west), the tendency to return to the texts of the two masters (ad fontes) for their defense, which had started even before the domination of Christianity, intensified. Accordingly, while the classification of the different parts of philosophy continued to be presented as a virtual blueprint for a potential philosophical summa, the main form of philosophical discourse was the individual treatise on one or more of related themes and, predominantly, the commentary on the works of “divine” Plato and, by the sixth century, also “divine” Aristotle. When philosophy was resuscitated after a hiatus of about two centuries (ca. 600–800) with the translation and paraphrase, in Arabic this time, of the canonical source texts (Gutas 2004a), these compositional practices reappeared. But the social context in which philosophy now found itself had changed. The literate population in the Islamic near and farther East during the early Abbasid period was favorably disposed toward philosophy as a rational scientific system, and with the different parts of this system—the philosophical curriculum—broadly known in its range if not in detail, it was possible, indeed expected, that an educated layman like Avicenna’s neighbor in Bukhara, Abū-l-Ḥasan Aḥmad ibn-ʿAbdallāh al-ʿArūḍī (I give his full name because he deserves to be noted in a history of philosophy), would be interested to have and read a comprehensive account of the entire discipline and to commission such a work from the youthful Avicenna. Avicenna complied, and thus was born the first philosophical summa treating in a systematic and consistent fashion within the covers of a single book all the branches of logic and theoretical philosophy as classified in the Aristotelian tradition. That Avicenna was able to produce such a work (and repeat it seven more times thenceforth) is of course a tribute to his genius (universally acknowledged both then and now), but that the request for it should have come from his society is telling evidence of its cultural attitude regarding science.