Though it has been said that he suffered from syphilis apparently he was found to have had some form of brain tumour. A sad life which was all too brief but one for which many of us are greatful.
Sorry, the "injury to the hand" MYTH is wrong. Please look up his medical history. There are many possible reasons why his nervous system stopped functioning, so that, starting with his hands, he could not operate his fingers, then would have periodique complete paralysis, following with probable schizophrenia and bipolar problems!
I wrote a paper on him. Very likely had syphilis. The treatment of which at the time was mercury. In researching my paper I read about the fishing village of Minamata in Japan. The villagers were unknowingly ingesting Mercury. This lead to Minamata disease which includes, tinnitus, numbness in extremities, vision problems all of which Schumann had. Also (I don’t remember the word for this) but it causes hands and feet to become very rigid and kind of “crumpled.” I believe that Schumann had Minamata disease. The device he was using that supposedly injured his hand was probably being used in a futile attempt to “un-crumple” his hands which were being affected by that disease….Also another symptom of Minamata disease is SEVERE mental/psychological problems which Schumann also had.
