Intelligence and IQ

What Austrian physicist, born on this day in 1844, hanged himself just before his theories were proven correct? 

Describing the highest quality of exposition shared by the giants in mathematics and music, he once stated, “A mathematician will recognize Cauchy, Gauss, Jacobi or Helmholtz after reading a few pages, just as musicians recognize, from the first few bars, Mozart, Beethoven or Schubert.”