It is, in the first place, urged that the moral and humanitarian teaching which the Christian Churches never ceased to put before the world condemned in advance every departure from the paths of justice and charity; that it was not the fault of Christianity if men refused to listen to or carry into practice that teaching. But at no period in the history of morals has it sufficed to lay down general principles. Everybody perceives to-day, not only that slavery was in itself a crime, but that it was essentially opposed to the Christian morality. Yet, as no Christian teacher for many centuries ventured to apply the principle by expressly denouncing slavery, the institution was taken over from Paganism by Christian Europe and lasted centuries after the fall of the Roman Empire. The Church itself had vast numbers of slaves, and later of serfs, on its immense estates. Leo the Great disdainfully enacted that the priesthood must not be stained by admitting so "vile" a class to its ranks, and Gregory the Great had myriads of slaves on the Papal "patrimonies." So it was with the demand for social reform which characterised the nineteenth century. To-day Christians claim that their principles sanctioned and gave weight to those early demands of reform, yet their principles had been vainly repeated in Europe for fifteen hundred years, and, when the people themselves at last formulated their demands in the early part of the nineteenth century, it is notorious that the clergy opposed them. The teaching of abstract moral principles is of no avail. Man is essentially a casuist. Leave to him the application of your principles, and he will adapt almost any scheme of conduct to them. The moralist who does not boldly and explicitly point the application of his principles is either too ignorant of human nature to discharge his duty with effect or is a coward. The plain fact is that the preaching of justice and peace throughout Europe has been steadily accompanied by an increase in armaments and in international friction. It had no moral influence on the situation. A more valid plea is that we must distinguish carefully between the nations which inaugurated the war and the nations which are merely defending themselves, and we must quarrel with the Christian Churches only in those lands which are guilty. It may, indeed, be pleaded that, since each nation regards itself as acting on the defensive and uses arguments to this effect which convince its jurists and scholars no less than its divines, there is no occasion at all to introduce Christianity. Most of us do not merely admit the right, we emphasise the duty, of every citizen to take his share in the just defence of his country, either by arms or by material contribution. Since there seems to be a general conviction even in Germany and Austria that the nation is defending itself against jealous and designing neighbours, why quarrel with their clergy for supporting the war?