Richard Wagner was, after Beethoven, the most influential of all nineteenth-century composers. His strictly musical innovations, in harmony and orchestration, revolutionized instrumental music as well as opera. In terms of opera, Wagner is famous for his novel concept of the “total work of art” (Gesamtkunstwerk) and his development of a special operatic technique, that of the “guiding motive” (leitmotiv).

Unlike earlier innovative composers, it seems Wagner could not just compose. He had to develop elaborate theories announcing what art, music, and opera ought to be like. (Indeed, he also theorized about politics and philosophy, with very unhappy results.) Wagner’s extreme self-consciousness as an artist was prophetic of attitudes toward art of a later period.

His theory of opera had its positive and negative sides. First, Wagner wanted to do away with all the conventions of earlier opera, especially the French and Italian varieties. Opera, he complained, had degenerated from its original form as serious drama in music — Wagner was thinking of ancient Greek drama, which he knew had been sung or at least chanted — into a mere concert in costume. He particularly condemned arias, which were certainly at the heart of Italian opera, as hopelessly artificial. Why should the dramatic action keep stopping to allow for stretches of pretty but undramatic singing?