It is safe to say that the political categories determined by Islam are by nature rather paltry, and – because of the obscurity of their origins – not open to straightforward interpretation. As we have seen, the terms caliph and caliphate gave way to king and kingdom even before they had acquired significance in terms of the naked exercise of power, while the umma remained the abstract community of Muslims, a kind of loose collective which nevertheless symbolises to this day the virtual Islamic community – especially when Islam has to be defined as distinct from the other/otherness. We may regard ijmāc and ijtihād as scarcely more than virtual institutions of the virtual umma, which have the possibility of dancing between the chains, and the latter not for long at that. As a homologous category of the umma, sharica is an expression of the divine nomokratia of Islamic society, and at the same time – in the flexible interpretation of certain experts on religious law once Muslim institutions had become impossible – renders possible or at least tolerates the patrimonial jurisdiction of dynastic exercise of power – mainly of nomad origin. This last becomes the subject of Ibn Khaldūn's theory of civilisation, which dissects with peerless originality the building up and functioning of the patrimonial empires of nomadic origin which had their Lebensraum on the Eurasian steppe. In order to establish the peculiar character of this, by a fascinating and unique achievement he laid the foundation of the science of history2, the subject of which is the creation of civilisation and its "metabolism"3, and for the theoretical building-up of which he had to create a new method4 , and for that a new system of categories.5 In so doing he firmly rejected the idea of going into the heterogenous, heteronomous, unattained concrete quality of the "real subject", and realised that he had to build up theoretically "the structure of the subject of knowledge".6 This he could only do by working out a new doctrine of categories, because he could not find in the work of his forebears categories that could be transferred to his new theory of civilisation.7 The intellectual fruit of his achievement, the theoretical construction of the patrimonial empires of the Eurasian steppe zone,8 with the corresponding limits, in the sphere of nomothetic analysis of historical processes, is to be compared with little other than the work of Marx and Weber: in Das Kapital (and even more so in his Grundrisse), the former sought to analyse the "epistemology" of capitalism by previously unused categories; the latter worked out the ideal types of radically new socialisation represented by developing capitalism (as the telos of human history). In the case of Ibn Khaldūn, there also followed necessarily from his "epistemological caesura" (his radical breaking away from earlier historical depictions) the elaboration of a consistent scheme of categories, which had nothing in common with the concepts prescribed by Islam. Let us take a look at the most important.9