As regards commonwealths, this return to the point of departure is brought about either by extrinsic accident or by intrinsic foresight.  As to the first, we have seen how it was necessary that Rome should be taken by the Gauls, that being thus in a manner reborn, she might recover life and vigour, and resume the observances of religion and justice which she had suffered to grow rusted by neglect.  This is well seen from those passages of Livius wherein he tells us that when the Roman army was ’sent forth against the Gauls, and again when tribunes were created with consular authority, no religious rites whatever were celebrated, and wherein he further relates how the Romans not only failed to punish the three Fabii, who contrary to the law of nations had fought against the Gauls, but even clothed them with honour.  For, from these instances, we may well infer that the rest of the wise ordinances instituted by Romulus, and the other prudent kings, had begun to be held of less account than they deserved, and less than was essential for the maintenance of good government.

And therefore it was that Rome was visited by this calamity from without, to the end that all her ordinances might be reformed, and the people taught that it behoved them not only to maintain religion and justice, but also to esteem their worthy citizens, and to prize their virtues beyond any advantages of which they themselves might seem to have been deprived at their instance.  And this, we find, was just the effect produced.  For no sooner was the city retaken, than all the ordinances of the old religion were at once restored; the Fabii, who had fought in violation of the law of nations, were punished; and the worth and excellence of Camillus so fully recognized, that the senate and the whole people, laying all jealousies aside, once more committed to him the entire charge of public affairs.

It is necessary then, as I have said already, that where men dwell together in a regulated society, they be often reminded of those ordinances in conformity with which they ought to live, either by something inherent in these, or else by some external accident.  A reminder is given in the former of these two ways, either by the passing of some law whereby the members of the society are brought to an account; or else by some man of rare worth arising among them, whose virtuous life and example have the same effect as a law.  In a Commonwealth, accordingly, this end is served either by the virtues of some one of its citizens, or by the operation of its institutions.

The institutions whereby the Roman Commonwealth was led back to its starting point, were the tribuneship of the people and the censorship, together with all those laws which were passed to check the insolence and ambition of its citizens.  Such institutions, however, require fresh life to be infused into them by the worth of some one man who fearlessly devotes himself to give them effect in opposition to the power of those who set them at defiance.