+91. Possibility of modifying mores.+ The combination in the mores of persistency and variability determines the extent to which it is possible to modify them by arbitrary action. It is not possible to change them, by any artifice or device, to a great extent, or suddenly, or in any essential element; it is possible to modify them by slow and long-continued effort if the ritual is changed by minute variations. The German emperor Frederick II was the most enlightened ruler of the Middle Ages. He was a modern man in temper and ideas. He was a statesman and he wanted to make the empire into a real state of the absolutist type. All the mores of his time were ecclesiastical and hierocratic. He dashed himself to pieces against them. Those whom he wanted to serve took the side of the papacy against him. He became the author of the laws by which the civil institutions of the time were made to serve ecclesiastical domination. He carried the purpose of the crusades to a higher degree of fulfillment than they ever reached otherwise, but this brought him no credit or peace. The same drift in the mores of the time bore down the Albigenses when they denounced the church corporation, the hierarchy, and the papacy. The pope easily stirred up all Europe against them. The current opinion was that every state must be a Christian state according to the mores of the time. The people could not conceive of a state which could answer its purpose if it was not such. But a "Christian state" meant one which was in harmony with the pope and the ecclesiastical organization. This demand was not affected by the faults of the organization, or the corruption and venality of the hierarchy. The popes of the thirteenth century rode upon this tide, overwhelming opposition and consolidating their power. In our time the state is charged with the service of a great number of interests which were then intrusted to the church. It is against our mores that ecclesiastics should interfere with those interests. There is no war on religion. Religion is recognized as an interest by itself, and is treated with more universal respect than ever before, but it is regarded as occupying a field of its own, and if there should be an attempt in its name to encroach on any other domain, it would fail, because it would be against the mores of our time.