But such events are rare; they are exceptions, the cause of which is always to be found in the particular constitution of the State concerned. They cannot even happen twice to the same people, for it can make itself free as long as it remains barbarous, but not when the civic impulse has lost its vigour. Then disturbances may destroy it, but revolutions cannot mend it: it needs a master, and not a liberator. Free peoples, be mindful of this maxim: “Liberty may be gained, but can never be recovered.”