"modern history," which included what we now call the Middle Ages.
In this sequence three particular epochs stand out as fertile in
science and favourable to progress--the Greek, the Roman, and our
own--"and scarcely two centuries can with justice be assigned to
each." The other periods of time are deserts, so far as philosophy
and science are concerned. Rome and Greece are "two exemplar States
of the world for arms, learning, moral virtue, policy, and laws."
But even in those two great epochs little progress was made in
natural philosophy. For in Greece moral and political speculation
absorbed men's minds; in Rome, meditation and labour were wasted on
moral philosophy, and the greatest intellects were devoted to civil
affairs. Afterwards, in the third period, the study of theology was
the chief occupation of the Western European nations. It was
actually in the earliest period that the most useful discoveries for
the comfort of human life were made, "so that, to say the truth,
when contemplation and doctrinal science began, the discovery of
useful works ceased."

So much for the past history of mankind, during which many things
conspired to make progress in the subjugation of nature slow,
fitful, and fortuitous. What of the future? Bacon's answer is: if
the errors of the past are understood and avoided there is every
hope of steady progress in the modern age.

But it might be asked. Is there not something in the constitution of
things which determines epochs of stagnation and vigour, some force
against which man's understanding and will are impotent? Is it not
true that in the revolutions of ages there are floods and ebbs of
the sciences, which flourish now and then decline, and that when
they have reached a certain point they can proceed no further? This