The gradual organization of the Inquisition was simply a process of evolution arising from the mutual reaction of the social forces which we have described. The Albigensian Crusades had put an end to open resistance, yet the heretics were none the less numerous, and, if less defiant, were only the more difficult to discover. The triumph of force had increased the responsibility of the Church, while the imperfection of its means of discharging that responsibility was self-confessed in the enormous spread of heresy during the twelfth century. We have seen the confused and uncertain manner in which the local prelates had sought to meet the new demands upon them. When the existence of hidden crime is suspected there are three stages in the process of its suppression—the discovery of the criminal, the proof of his guilt, and finally his punishment. Of all others the crime of heresy was the most difficult to discover and to prove, and when its progress became threatening the ecclesiastics on whom fell the responsibility of its eradication were equally at a loss in each of the three steps to be taken for its extermination.

Immersed, for the most part, in the multiplied troubles connected with the overgrown temporalities of their sees, the bishops would await popular rumor to designate some man or group of men as heretical.