said already, there is not a trace of the notion that the Emperor reigns by an hereditary right of his own or by the will of the people, for such a theory would have seemed to the men of the middle ages an absurd and wicked perversion of the true order. Nor do his powers come to him from those who choose him, but from God, who uses the electoral princes as mere instruments of nomination. Having such an origin, his rights exist irrespective of their actual exercise, and no voluntary abandonment, not even an express grant, can impair them. Boniface the Eighth[281] reminds the king of France, and imperialist lawyers till the seventeenth century repeated the claim, that he, like other princes, is of right and must ever remain subject to the Roman Emperor. And the sovereigns of Europe long continued to address the Emperor in language, and yield to him a precedence, which admitted the inferiority of their own position[282]. There was in this theory nothing that was absurd, though much that was impracticable. The ideas on which it rested are still unapproached in grandeur and simplicity, still as far in advance of the average thought of Europe, and as unlikely to find men or nations fit to apply them, as when they were promulgated five hundred years ago. The practical evil which the establishment of such a universal monarchy was intended to meet, that of wars and hardly less ruinous preparations for war between the states of Europe, remains what it was then. The remedy which mediæval theory proposed has been in some measure applied by the construction and reception of international law; the greater difficulty of erecting a tribunal to arbitrate and decide, with the power of enforcing its decisions, is as far from a solution as ever. [Sidenote: Roman Empire why an international power.]