During the final 9 years of his life he created a series of character heads holding the intense expresions for hours while he carved them in marble.
It has been argued by more recent art historians that Franz Xaver was suffering from paranoia, hallucinations and mental health problems or Crohns disease a digestive disorder.
It is difficult not to feel a sadness in the story of the sculptor, let go from his post at the Art Academy because of his state of mind, finishing his life spending his time producing a series of painfully accurate self portraits before dying in his mid 40s