The history of institutions,’ says Acton, ‘is often a history of deception and illusions.’ Arrangements which in their beginnings promoted a dispersion of power often, in the course of time, themselves become over-mighty or even absolute while still claiming the recognition and loyalty which belonged to them in respect of their first character. To further liberty we need to be clear-sighted enough to recognise such a change, and energetic enough to set on foot the remedy while the evil is still small. And what more than anything else contributes to this clear-sightedness is relief from the distraction of a rigid doctrine which fixes upon an institution a falsely permanent character, and then (when the illusion is at last recognised) calls for a revolution.