 Fârâbî does not seem to know about the metaphysics of the Republic, and in any case it would not give him what he needs. He fills in the content of the metaphysics from elsewhere, from Metaphysics XII as he would like it to be, guided by later Greek interpreters—Themistius’ commentary, and texts of Plotinus and Proclus in their Arabic adaptations. This goes beyond the actual Metaphysics XII both in that it infers to God as a first cause of existence rather than of motion, and in that it includes a downward way from God to the beings that derive their existence from  him.[41]  Fârâbî is also much more systematic than Aristotle, in the manner of a kalâm treatise, in showing that God is simple, i.e., free from all the different modes of composition, and is unique and has no contrary (all things that Metaphysics XII does briefly say), and in going through a whole series of attributes of God. It is plausible that both treatises are directed to potential princely patrons, perhaps after Fârâbi’s departure from Baghdad for Aleppo and Damascus late in his life. Fârâbî would be trying to break falsafa out of its Christian (or Ismâʿîlî) ghetto and to present it as a “religious science” superior to kalâm, not exclusively Muslim but suited for Muslim needs: Fârâbî presents falsafa as giving the content of the ruler’s or his adviser’s religious knowledge, and implicitly presents himself as an adviser to  princes.[42]  Thus both the Perfect City and the Political Regime are supposed to be intelligible to a non-specialist audience. In neither case does Fârâbi show himself struggling with a difficult Greek model, and while he draws on his technical analyses of being and unity from the Book of Letters and On the One, this technical substructure is tastefully concealed. The Political Regime seems to stay closer to Fârâbî’s Greek  models,[43]  and may thus be the earlier of the two texts, while in the Perfect City he seems to have more fully digested those models and to be presenting the results in a simpler and more independent form, concentrating on the elements more central to presenting falsafa as a “religious science” to a contemporary Muslim audience. But some passages remain verbally identical or almost identical in the two  treatises.[44]