Grétry founded a school of musical composition in France which has since been cultivated with signal success--that of lyric comedy. The efforts of Lulli and Rameau had been turned in another direction. The former had done little more than set courtly pageants to music, though he had done this with great skill and tact, enriching them with a variety of concerted and orchestral pieces, and showing much fertility in the invention alike of pathetic and lively melodies. Rameau followed in the footsteps of Lulli, but expanded and crystallised his ideas into a more scientific form. He had indeed carried his love of form to a radical extreme. Jean Jacques Rousseau, who extended his taste for nature and simplicity to music, blamed him severely as one who neglected genuine natural tune for far-fetched harmonies, on the ground that "music is a child of nature, and has a language of its own for expressing emotional transports, which cannot be learned from thorough-bass rules." Again, Rousseau, in his forcible tract on French music, says of Rameau, from whose school Grétry's music was such a significant departure-- "One must confess that M. Rameau possesses very great talent, much fire and euphony, and a considerable knowledge of harmonious combinations and effects; one must also grant him the art of appropriating the ideas of others by changing their character, adorning and developing them, and turning them around in all manner of ways. On the other hand, he shows less facility in inventing new ones. Altogether he has more skill than fertility, more knowledge than genius, or rather genius smothered by knowledge, but always force, grace, and very often a beautiful _cantilena_. His recitative is not as natural but much more varied than that of Lulli; admirable in a few scenes, but bad as a rule." Rousseau continues to reproach Rameau with a too powerful instrumentation, compared with Italian simplicity, and sums up that nobody knew better than Rameau how to conceive the spirit of single passages and to produce artistic contrasts, but that he entirely failed to give his operas "a happy and much-to-be-desired unity." In another part of the quoted passage Rousseau says that Rameau stands far beneath Lulli in _esprit_ and artistic tact, but that he is often superior to him in dramatic expression.