A new recording throws fresh light on Mahler’s puzzling Tenth Symphony

There are many Symphonies No. 10 by Gustav Mahler, or none. The situation is rare, if not unique, in the history of music. Basic facts: Mahler finished the Ninth Symphony and Das Lied von der Erde in the summer of 1910. At the same time he discovered that his wife Alma was having an affair with Gropius, and that he had an incurable heart complaint and hadn’t long to live. One might have thought that these last two completed works are as movingly valedictory as anything ever written, but Mahler’s view was more complicated than that, and he immediately set about writing a Tenth Symphony. Over and among the notes,