Beethoven was the model for the misunderstood, born-too-soon creative genius—at least as far as composers are concerned—and Gustav Mahler was his most apt pupil. In the decades just before and after 1900, while building a reputation throughout Europe and New York as one of the world’s great conductors, he also turned out a series of large, hyperexpressive, and tonally ambiguous symphonies that many listeners greeted with incomprehension or outright hostility. Mahler, though often aggrieved, was confident that classical audiences would come around to him, as they had to Beethoven. Referring to