"But I don't know the prince, and the dedicatory epistle embarrasses
me." "Sit down," said Diderot, "and I will write one for you." The
dedication was written, the author carried it to the prince, and
received a handsome fee.[10]

Marmontel assures us that never was Diderot seen to such advantage as
when an author consulted him about a work. "You should have seen him,"
he says, "take hold of the subject, pierce to the bottom of it, and at a
single glance discover of what riches and of what beauty it was
susceptible. If he saw that the author missed the right track, instead
of listening to the reading, he at once worked up in his head all that
the author had left crude and imperfect. Was it a play, he threw new
scenes into it, new incidents, new strokes of character; and thinking
that he had actually heard all that he had dreamed, he extolled to the
skies the work that had just been read to him, and in which, when it saw
the light, we found hardly anything that he had quoted from it.... He
who was one of the most enlightened men of the century, was also one of
the most amiable; and in everything that touched moral goodness, when he
spoke of it freely, I cannot express the charm of his eloquence. His
whole soul was in his eyes and on his lips; never did a countenance
better depict the goodness of the heart."[11] Morellet is equally loud
in praise, not only of Diderot's conversation, its brilliance, its
vivacity, its fertility, its suggestiveness, its sincerity, but also
his facility and indulgence to all who sought him, and of the
sympathetic readiness with which he gave the very best of himself to
others.[12]

It is needless to say that such a temper was constantly abused.
Three-fourths of Diderot's life were reckoned by his family to have been
given up to people who had need of his purse, his knowledge, or his good