To this very thorough presentation of the claims of the ecclesiastical power the partisans of secular authority had only a half-hearted doctrine to oppose. Ever since the days of Pope Gelasius I (492-6), the Church herself had accepted the view of a strict dualism in the organisation of society and, therefore, of the theoretical equality between the ecclesiastical and the secular organs of government. According to this doctrine Sacerdotium and Imperium are independent spheres, each wielding the one of the two swords appropriate to itself, and thus the Emperor no less than the Pope is _Vicarius Dei_. It is this doctrine behind which the champions of the Empire entrench themselves in their contest with the Papacy. It was asserted by the Emperors themselves, notably by Frederick I and Frederick II, and it has been enshrined in the writings of Dante. [Sidenote: Its weakness.] The weak point of this theory was that it was rather a thesis for academic debate than a rallying cry for the field of battle. Popular contests are for victory, not for delimitation of territory. And its weakness was apparent in this, that while the thorough-going partisans of the Church allowed to the Emperor practically no power except such as he obtained by concession of or delegation from the Church, the imperial theory granted to the ecclesiastical representative at least an authority and independence equal to those claimed for itself, and readily admitted that of the two powers the Church could claim the greater respect as being entrusted with the conduct of matters that were of more permanent importance. Moreover, historical facts contradicted this idea of equality of powers. The Church through her representatives often interfered with decisive effect in the election and the rejection of secular potentates up to the Emperor himself: she claimed that princes were as much subject to her jurisdiction as other laymen, and she did not hesitate to make good that claim even to the excommunication of a refractory ruler and--its corollary--the release of his subjects from their oath of allegiance. Finally, the Church awoke a responsive echo in the hearts of all those liable to oppression or injustice, when she asserted a right of interposing in purely secular matters for the sake of shielding them from wrong; while she met a real need of the age in her exaltation of the papal power as the general referee in all cases of difficult or doubtful jurisdiction. Thus the claims of each power as against the other were not at all commensurate. For while the imperialists would agree that there was a wide sphere of ecclesiastical rule with which the Emperor had no concern at all, it was held by the papalists that there was nothing done by the Emperor in any capacity which it was not within the competence of the Pope to supervise. CHAPTER I THE BEGINNINGS OF CHURCH REFORM