There was, however, one other great undertaking of his time in which it would seem that the Pontiff was more directly influential, even though, for any reader who respects the character and ideal of Innocent, it is sickening to the heart to realise what it was. It was that other Crusade, so miserable and so bloody, against the Albigenses, which was the only successful enterprise which with any show of justice could be set down to the account of the Church. Nobody seems even now to know very well what the heresies were, against which, in the failure of other schemes, the arms of the defenders of religion were directed. They were, as Dissent generally is, manifold, while the Church regarded them as one. Among them were humble little sects who desired only to lead a purer and truer life than the rude religionists among whom they dwelt; while there were also others who held in various strange formulas all kinds of wild doctrine: but between the Poor Men of Lyons, the Scripture-Readers whose aim was to serve God in humility, apart from all pomps of religion and splendour of hierarchies--and the strange Manichean sects with their elaborate and confused philosophical doctrine--the thirteenth century knew no difference. It ranked them all under the same name of heretic, and attributed to all of them the errors of the worst and smallest section. Even so late as the eighteenth century, Muratori, a scholar without prejudice, makes one sweeping assertion that they were Manicheans, without a doubt or question. It is needless to say that whatever they were, fire and sword was not the way to mend them of their errors; for that also was an idea wholly beyond the understanding of the time.