In this, if in nothing else, he agreed with Creighton. His correspondence with the latter throws his principles into the strongest light, and forms the best material for a judgment. For it must, we think, be admitted that he applied these doctrines with a rigidity which human affairs will not admit, and assumed a knowledge beyond our capacity. To declare that no one could be in a state of grace who praised S. Carlo Borromeo, because the latter followed the evil principle of his day in the matter of persecution, is not merely to make the historian a hanging judge, but to ignore the great truth that if crime is always crime, degrees of temptation are widely variable. The fact is, Acton's desire to maintain the view that "morality is not ambulatory," led him at times to ignore the complementary doctrine that it certainly develops, and that the difficulties of statesmen or ecclesiastics, if they do not excuse, at least at times explain their less admirable courses. At the very close of his life Acton came to this view himself. In a pathetic conversation with his son, he lamented the harshness of some of his judgments, and hoped the example would not be followed. Still, Acton, if he erred here, erred on the nobler side. The doctrine of moral relativity had been overdone by historians, and the principles of Machiavelli had become so common a cry of politicians, that severe protest was necessary. The ethics of Nietzsche are the logical expansion of Machiavelli, and his influence is proof that, in the long-run, men cannot separate their international code from their private one. We must remember that Acton lived in a time when, as he said, the course of history had been "twenty-five times diverted by actual or attempted crime," and when the old ideals of liberty seemed swallowed up by the pursuit of gain. To all those who reflect on history or politics, it was a gain of the highest order that at the very summit of historical scholarship and profound political knowledge there should be placed a leader who erred on the unfashionable side, who denied the statesmen's claim to subject justice to expediency, and opposed the partisan's attempt to palter with facts in the interest of his creed.