It was only toward the end of the 19th century that the newly emergent discipline of Musikwissenschaft (musicology)—itself a product of the historicizing proclivity of the age—attempted a more scientific periodization of music history, and a distinction between Viennese Classical and Romantic periods was proposed. The key figure in this trend was Guido Adler, who viewed Beethoven and Franz Schubert as transitional but essentially Classical composers, with Romanticism achieving full maturity only in the post-Beethoven generation of Frédéric Chopin, Robert Schumann, Berlioz, and Franz Liszt. From Adler's viewpoint, found in books like Der Stil in der Musik (1911), composers of the New German School and various late-19th-century nationalist composers were not Romantics but "moderns" or "realists" (by analogy with the fields of painting and literature), and this schema remained prevalent through the first decades of the 20th century