after the war, the massacre of the Coreyrean oligarchs by the
democratic party, the slaughter of the Thebans by Alexander and
of the Corinthians by Mummius are among the more familiar
instances of the catastrophes which overtook the civic element
in the Greek cities. The void can only have been filled from
the ranks of the metics or resident aliens and of the
descendants of the far more numerous slave population. In the
classic period four fifths of the population of Attica were
slaves; of the remainder, half were meties In A.D. 100 only
three thousand free arm-bearing men were in Greece. (James D.
Bourchier.)

The constant little struggles of the Greeks among themselves
made no great showing as to numbers compared to other wars, but
they wiped out the most valuable people, the best blood, the
most promising heredity on earth. This cost the world more than
the killing of millions of barbarians. In two centuries there
were born under the shadow of the Parthenon more men of genius
than the Roman Empire had in its whole existence. Yet this
empire included all the civilized world, even Greece herself.
(La Pouge.)

The downfall of Greece,[6] like that of Rome, has been ascribed
by Schultz to the crossing of the Greeks with the barbaric
races which flocked into Hellas from every side. These resident
aliens, or metics, steadily increased in number as the free
Greeks disappeared. Selected slaves or helots were then made
free in order to furnish fighting men, and again as these fell
their places were taken by immigrants.