the doctrine of a gradual sequence of social and material
improvements [Footnote: In the masterly survey of early Greek
history which Thucydides prefixed to his work, he traces the social
progress of the Greeks in historical times, and finds the key to it
in the increase of wealth.] during the subsequent period of decline.
We find the two views thus combined, for instance, in Plato's Laws,
and in the earliest reasoned history of civilisation written by
Dicaearchus, a pupil of Aristotle. [Footnote: Aristotle's own view
is not very clear. He thinks that all arts, sciences, and
institutions have been repeatedly, or rather an infinite number of
times (word in Greek) discovered in the past and again lost.
Metaphysics, xi. 8 ad fin.; Politics, iv. 10, cp. ii. 2. An infinite
number of times seems to imply the doctrine of cycles.] But the
simple life of the first age, in which men were not worn with toil,
and war and disease were unknown, was regarded as the ideal State to
which man would lie only too fortunate if he could return. He had
indeed at a remote time ill the past succeeded in ameliorating some
of the conditions of his lot, but such ancient discoveries as fire
or ploughing or navigation or law-giving did not suggest the guess
that new inventions might lead ultimately to conditions in which
life would be more complex but as happy as the simple life of the
primitive world.

But, if some relative progress might be admitted, the general view
of Greek philosophers was that they were living in a period of
inevitable degeneration and decay--inevitable because it was
prescribed by the nature of the universe. We have only an imperfect
knowledge of the influential speculations of Heraclitus, Pythagoras,
and Empedocles, but we may take Plato's tentative philosophy of
history to illustrate the trend and the prejudices of Greek thought