The second tendency against which Acton's moral sense revolted, had arisen out of the laudable determination of historians to be sympathetic towards men of distant ages and of alien modes of thought. With the romantic movement the early nineteenth century placed a check upon the habit of despising mediaeval ideals, which had been increasing from the days of the Renaissance and had culminated in Voltaire. Instead of this, there arose a sentiment of admiration for the past, while the general growth of historical methods of thinking supplied a sense of the relativity of moral principles, and led to a desire to condone if not to commend the crimes of other ages. It became almost a trick of style to talk of judging men by the standard of their day and to allege the spirit of the age in excuse for the Albigensian Crusade or the burning of Hus. Acton felt that this was to destroy the very bases of moral judgment and to open the way to a boundless scepticism. Anxious as he was to uphold the doctrine of growth in theology, he allowed nothing for it in the realm of morals, at any rate in the Christian era, since the thirteenth century. He demanded a code of moral judgment independent of place and time, and not merely relative to a particular civilisation. He also demanded that it should be independent of religion. His reverence for scholars knew no limits of creed or church, and he desired some body of rules which all might recognise, independently of such historical phenomena as religious institutions. At a time when such varied and contradictory opinions, both within and without the limits of Christian belief, were supported by some of the most powerful minds and distinguished investigators, it seemed idle to look for any basis of agreement beyond some simple moral principles. But he thought that all men might agree in admitting the sanctity of human life and judging accordingly every man or system which needlessly sacrificed it. It is this preaching in season and out of season against the reality of wickedness, and against every interference with the conscience, that is the real inspiration both of Acton's life and of his writings.