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.