stages of timocracy, oligarchy, democracy, and despotism. He
explains this deterioration as primarily caused by a degeneration of
the race, due to laxity and errors in the State regulation of
marriages, and the consequent birth of biologically inferior
individuals.

The theories of Plato are only the most illustrious example of the
tendency characteristic of Greek philosophical thinkers to idealise
the immutable as possessing a higher value than that which varies.
This affected all their social speculations. They believed in the
ideal of an absolute order in society, from which, when it is once
established, any deviation must be for the worse. Aristotle,
considering the subject from a practical point of view, laid down
that changes in an established social order are undesirable, and
should be as few and slight as possible. [Footnote: Politics, ii.
5.] This prejudice against change excluded the apprehension of
civilisation as a progressive movement. It did not occur to Plato or
any one else that a perfect order might be attainable by a long
series of changes and adaptations. Such an order, being an
embodiment of reason, could be created only by a deliberate and
immediate act of a planning mind. It might be devised by the wisdom
of a philosopher or revealed by the Deity. Hence the salvation of a
community must lie in preserving intact, so far as possible, the
institutions imposed by the enlightened lawgiver, since change meant
corruption and disaster. These a priori principles account for the
admiration of the Spartan state entertained by many Greek
philosophers, because it was supposed to have preserved unchanged
for an unusually long period a system established by an inspired
legislator.