 If this hypothesis is tenable, Epistle 31 contains not only the core of the Ikhwân's political thought, but also of their Ismâ‘îli commitment. Their presentation of the “perfect city,” in which mutual love is the basis and the goal of the community, does not help us to ascertain whether the Ikhwân have in mind spiritual rule or a true government such as that of the Fatimid caliph, of whom they might be the du‘â’. Scholars tend to consider this “perfect city” as utopian as the Farabian (cf. e.g. Marquet 1973, 153; Hamdani 1999, 81). The defeat of evil people is also often foreshadowed in the encyclopedia (cf. e.g. Epistle 31, III, 154, 19–24 and 156, 2–3). In Epistle 4 the Ikhwân present a cyclical conception of ruling dynasties, and state that “the dynasty of the evil reached its apex,” hence only decline and diminution are to be expected in the future. According to Tibawi (1955, 37, note 4), the Ikhwân forebode here the fall of the ‘Abbasids. Cf. also Tibawi, 1978, 60.) The dynasty of the good begins when the learned agree “on a unique doctrinal school and a single religion,” commit themselves to mutual help, and desire the vision of God and doing God's will as their [sole] reward (I, 181, 14–182, 2). In Epistle 48, the Ikhwân declare that the one whose advent in the world is expected is coming, and it will be a wonderful event (IV, 190, 13), in which the welfare of both religion and the world will be gathered. Magic, astronomy and true dreams helped them establish even the year and month of the advent of the “lord of the cycle” (sâhib al-amr) – but, of course, the date is not mentioned in the encyclopedia.