who was likely to dream dreams of social improvement. He was
temperamentally an Epicurean, of the same refined stamp as Epicurus
himself, and he enjoyed throughout his long life--he lived to the
age of a hundred--the tranquillity which was the true Epicurean
ideal. He was never troubled by domestic cares, and his own modest
ambition was satisfied when, at the age of forty, he was appointed
permanent Secretary of the Academy of Sciences. He was not the man
to let his mind dwell on the woes and evils of the world; and the
follies and perversities which cause them interested him only so far
as they provided material for his wit.

It remains, however, noteworthy that the author of the theory of the
progress of knowledge, which was afterwards to expand into a general
theory of human Progress, would not have allowed that this extension
was legitimate; though it was through this extension that
Fontenelle's idea acquired human value and interest and became a
force in the world.

9.

Fontenelle did a good deal more than formulate the idea. He
reinforced it by showing that the prospect of a steady and rapid
increase of knowledge in the future was certified.

The postulate of the immutability of the laws of nature, which has
been the indispensable basis for the advance of modern science, is
fundamental with Descartes. But Descartes did not explicitly insist
on it, and it was Fontenelle, perhaps more than any one else, who
made it current coin. That was a service performed by the disciple;
but he seems to have been original in introducing the fruitful idea