o it, but they are never mistaken.' 'Ah well, I at any rate know
how it is, and you have let me see much more in the matter than I
ever expected to learn from you,' and with that I turn my back on my
rascal." Diderot having occasion to visit the lieutenant of police,
introduced the matter, and could not withhold an energetic remonstrance
against such an odious abuse of a man's kindness of heart, as the
introduction of spies to his fireside. M. de Sartine laughed and Diderot
took his leave, vowing that all the wretches who should come to him for
the future, with cuffs dirty and torn, with holes in their stockings and
holes in their shoes, with hair all unkempt, in shabby overcoats with
many rents, or scanty black suits with starting seams, with all the
tones and looks of distressed worth, would henceforth seem to him no
better than police emissaries and scoundrels set to spy on him. The vow,
we may be sure, was soon forgotten, but the story shows how seriously in
one respect the man of letters in France was worse off than his brother
in England.

The world would have suffered no irreparable loss if the police had
thrown the Sceptic's Walk into the fire. It is an allegory designed to
contrast the life of religion, the life of philosophy, and the life of
sensual pleasure. Of all forms of composition, an allegory most depends
for its success upon the rapidity of the writer's eye for new
felicities. Accuracy, verisimilitude, sustention, count for nothing in
comparison with imaginative adroitness and variety. Bunyan had such an
eye, and so, with infinitely more vivacity, had Voltaire. Diderot had
not the deep sincerity or realism of conviction of the one; nor had he
the inimitable power of throwing himself into a fancy, that was
possessed by the other. He was the least agile, the least felicitous,
the least ready, of composers. His allegory of the avenue of thorns, the
avenue of chestnut-trees, and the avenue of flowers, is an allegory,
unskilful, obvious, poor, and not any more amusing than if it's matter
had been set forth without any attempt at fanciful decoration. The
blinded saints among the thorns, and the voluptuous sinners among the
flowers, are rather mechanical figures. The translation into the dialect
required by the allegorical situation, of a sceptic's aversion for gross
superstition on the one hand, and for gross hedonism on the other, is
forced and wooden. The most interesting of the three sections is the
secon