The significance of Weber's position in German opera must be found in the fact that in his theory of the musical drama he anticipated Wagner and paved the way for him. He defined opera as "an art work complete in itself, in which all the parts and contributions of the related and utilized arts meet and disappear in each other, and, in a manner, form a new world by their own destruction." He believed that a libretto should not be constructed with a view to its offering pegs upon which to hang strings of pretty music, but that there should be an organic union of the various arts employed in dramatic representation. His theory as to the purpose of lyric music was fully set forth in these words: "It is the first and most sacred duty of song to be truthful with the utmost fidelity possible in declamation." He furthermore had no sympathy with the rigid and restrictive formalism of the old-fashioned Italian opera, but was a thorough believer in the fundamental principle of romantic music, that the content must govern and prescribe the form: "All striving for the beautiful and the new good is praiseworthy, but the creation of a new form must be generated by the poem which is sitting." Mr. H. E. Krehbiel says in "Famous Composers and their Works," "Here we find stated in the plainest and most succinct terms the foundation principles of the modern lyric drama." These principles rest on the essential laws laid down originally by Peri, followed by Lulli and Rameau, and regenerated by Gluck. It was in following these principles and at the same time recognizing the characteristics of the German people and embodying them in his music that Weber formulated a style which has been a model and an inspiration to all the sincere composers of opera since his day. Wagner's debt to him was freely acknowledged, while Berlioz never wearied in expressing his admiration for the genius of Weber. To quote Mr. Krehbiel's masterly article once more: "To the band he gave a share in the representation such as only Beethoven, Mozart, and Gluck before him had dreamed of. The most striking feature of his treatment of the orchestra is his emancipation of the wood wind choir. His numerous discoveries in the domain of effects consequent on his profound study of instrumental _timbre_ placed colors upon the palettes of every one of his successors. The supernatural voices of his Wolf's Glen are echoed in Verdi as well as in Meyerbeer and Marschner. The fairy footsteps of Oberon's dainty folk are heard not only in Mendelssohn but in all the compositions since his time in which the amiable creatures of supernaturalism are sought to be delineated."