What Diderot conceived himself really to have done, was to have sketched and constituted a new species in the great dramatic kingdom.  Every one knows, he said, that there is tragedy and that there is comedy, but we have to learn that there is room in nature and the art of the stage for a third division, namely, the genre serieux, a kind of comedy that has for its object virtue and the duties of man.  Why should the writer of comedy confine his work to what is vicious or ridiculous in men?  Why should not the duties of men furnish the dramatist with as ample material as their vices?  Surely in the genre honnete et serieux the subject is as important as in gay comedy.  The characters are as varied and as original.  The passions are all the more energetic as the interest will be greater.  The style will be graver, loftier, more forcible, more susceptible of what we call sentiment, a quality without which no style ever yet spoke to the heart.  The ridiculous will not be absent, for the madness of actions and speeches, when they are suggested by the misunderstanding of interests or by the transport of passion, is the truly ridiculous thing in men and in life.[287]

Besides his own two pieces, Diderot would probably have pointed to Terence as the author coming nearest to the genre serieux.  If Goethe’s bad play of Stella had retained the close as he originally wrote it, with the bigamous Fernando in the last scene rejoicing over the devoted agreement of the two ladies and his daughter to live with him in happy unity, that would perhaps have been a comedy of the genre serieux, with the duties of man gracefully adapted to circumstances.

The theory of the genre serieux has not led to the formation of any school of writers adopting it and working it out, or to the production of any masterpiece that has held its ground, as has happened in tragedy, comedy, and farce.  Beaumarchais, who at last achieved such a dazzling and portentous success by one dramatic masterpiece, began his career as a playwright by following the vein of The Father of the Family; but The Marriage of Figaro, though not without strong traces of Diderotian sentiment in pungent application, yet is in its structure and composition less French than Spanish.  It is quite true, as Rosenkranz says, that the prevailing taste on the French stage in our own times favours above all else bourgeois romantic comedy, written in prose.[288] But the strength of the romantic element in them would have been as little satisfactory to Diderot’s love of realistic moralising as the conventional tragedy of the court of Lewis XIV.  The Fable of most of them turns on adultery, and this is not within the method of the genre serieux as expounded by Diderot.  Perhaps half a dozen comedies, such, for instance, as The Ideas of Madame Aubray, by M. Dumas, are of the genre serieux, but certainly there are not enough of such comedies to