inking
mournfully of her persecuted philosopher lying in prison. She forgot
that one of the parents of philosophy is curiosity, and that Diderot had
trained himself in the school of the sceptics. That evening he scaled
the walls of the park of Vincennes, flew to the scene of the festival,
and there found what he had expected. In vain for her had he written
upon virtue and merit, and the unhallowed friendship came to an end.

After three months of captivity, Diderot was released. The booksellers
who were interested in the Encyclopaedia were importunate with the
authorities to restore its head and chief to an enterprise that stirred
universal curiosity.[89] For the first volume of that famous work was
now almost ready to appear, and expectation was keen. The idea of the
book had occurred to Diderot in 1745, and from 1745 to 1765 it was the
absorbing occupation of his life. Of the value and significance of the
conception underlying this immense operation, I shall speak in the next
chapter. There also I shall describe its history. The circumstances
under which these five-and-thirty volumes were given to the world mark
Diderot for one of the few true heroes of literature. They called into
play some of the most admirable of human qualities. They required a
laboriousness as steady and as prolonged, a wariness as alert, a grasp
of plan as firm, a fortitude as patient, unvarying, and unshaken, as men
are accustomed to applaud in the engineer who constructs some vast and
difficult work, or the commander who directs a hardy and dangerous
expedition.

CHAPTER V.

THE ENCYCLOPAEDIA.

The history of the encyclopaedic conception of human knowledge is a much
more interesting and important object of inquiry than a list of the
various encyclopaedic enterprises to be found in the annals of
literature. Yet it is proper here to mention some of the attempts in
this direction, which preceded our memorable book of the eighteenth
century. It is to Aristotle, no doubt, that we must look for the first
glimpse of the idea that human knowledge is a totality, whose parts are
all closely and organically connected with one another. But the idea
that only dawned in that gigantic understanding was lost for many
centuries. The compilations of Pliny are not in a right sense
encyclopaedic, being presided over by no definite idea of informing
order. It was not until the later middle age that any attempt was made
to present knowledge as a whole.