It is certain, however, that such States can never be reformed without great risk; for, as a rule, men will accept no new law altering the institutions of their State, unless the necessity for such a change be demonstrated; and since this necessity cannot arise without danger, the State may easily be overthrown before the new order of things is established.

In proof whereof we may instance the republic of Florence, which was reformed in the year 1502, in consequence of the affair of Arezzo, but was ruined in 1512, in consequence of the affair of Prato.
Desiring, therefore, to discuss the nature of the government of Rome, and to ascertain the accidental circumstances which brought it to its perfection, I say, as has been said before by many who have written of Governments, that of these there are three forms, known by the names Monarchy, Aristocracy, and Democracy, and that those who give its institutions to a State have recourse to one or other of these three, according as it suits their purpose.

Other, and, as many have thought, wiser teachers, will have it, that there are altogether six forms of government, three of them utterly bad, the other three good in themselves, but so readily corrupted that they too are apt to become hurtful.

The good are the three above named; the bad, three others dependent upon these, and each so like that to which it is related, that it is easy to pass imperceptibly from the one to the other.

For a Monarchy readily becomes a Tyranny, an Aristocracy an Oligarchy, while a Democracy tends to degenerate into Anarchy.