The Classical Greek philosopher Plato discusses five types of regimes (Republic, Book VIII). They are Aristocracy, Timocracy, Oligarchy, Democracy, and Tyranny. Plato also assigns a man to each of these regimes to illustrate what they stand for. The tyrannical man would represent Tyranny, for example. These five regimes progressively degenerate starting with Aristocracy at the top and Tyranny at the bottom.

Aristocracy is the form of government (politeia) advocated in Plato's Republic. This regime is ruled by a philosopher king, and thus is grounded on wisdom and reason.

Aristocracy degenerates into timocracy when, due to miscalculation on the part of its governing class, the next generation of guardians and auxiliaries includes persons of an inferior nature (the persons with souls made of iron or bronze, as opposed to the ideal guardians and auxiliaries, who have souls made of gold and silver).

Plato defines oligarchy as a system of government which distinguishes between the rich and the poor, making out of the former its administrators.

Oligarchy then degenerates into democracy where freedom is the supreme good but freedom is also slavery.

Democracy then degenerates into tyranny where no one has discipline and society exists in chaos.

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