Our veteran humorist told us long ago in his whimsical way that the importance of the Acts of the French Philosophes recorded in whole acres of typography is fast exhausting itself, that the famed Encyclopaedical Tree has borne no fruit, and that Diderot the great has contracted into Diderot the easily measurable.  The humoristic method is a potent instrument for working such contractions and expansions at will.  The greatest of men are measurable enough, if you choose to set up a standard that is half transcendental and half cynical.  A saner and more patient criticism measures the conspicuous figures of the past differently.  It seeks their relations to the great forward movements of the world, and asks to what quarter of the heavens their faces were set, whether towards the east where the new light dawns, or towards the west after the old light has sunk irrevocably down.  Above all, a saner criticism bids us remember that pioneers in the progressive way are rare, their lives rude and sorely tried, and their services to mankind beyond price.  “Diderot is Diderot,” wrote one greater than Carlyle:  “a peculiar individuality; whoever holds him or his doings cheaply is a Philistine, and the name of them is legion.  Men know neither from God, nor from Nature, nor from their fellows, how to receive with gratitude what is valuable beyond appraisement” (Goethe).  An intense Philistinism underlay the great spiritual reaction that followed the Revolution, and not even such of its apostles as Wordsworth and Carlyle wholly escaped the taint.

Forty years ago, when Carlyle wrote, it might really seem to a prejudiced observer as if the encyclopaedic tree had borne no fruit.  Even then, and even when the critic happened to be a devotee of the sterile transcendentalism then in vogue, one might have expected some recognition of the fact that the seed of all the great improvements bestowed on France by the Revolution, in spite of the woful evils which followed in its train, had been sown by the Encyclopaedists.  But now that the last vapours of the transcendental reaction are clearing away, we see that the movement initiated by the Encyclopaedia is again in full progress.  Materialistic solutions in the science of man, humanitarian ends in legislation, naturalism in art, active faith in the improvableness of institutions—­all these are once more the marks of speculation and the guiding ideas of practical energy.  The philosophical parenthesis is at an end.  The interruption of eighty years counts for no more than the twinkling of an eye in the history of the transformation of the basis of thought.  And the interruption has for the present come to a close.  Europe again sees the old enemies face to face; the Church, and a Social Philosophy slowly labouring to build her foundations in positive science.  It cannot be other than interesting to examine the aims, the instruments, and the degree of success of those who a century ago saw most comprehensively how profound and far-reaching a metamorphosis awaited the thought of the Western world.  We shall do this most properly in connection with Diderot.