Phrenology was the attempt to correlate physical features of the brain and skull with personality, intellect, creativity.  You got your data by plundering graves.

The three categories of individuals who were most interesting for finding out about the human mind were criminals, the insane, and geniuses, in the sense that they represented the extreme versions of the human mind …. It was easy enough to get the heads of criminals and the insane. Nobody wanted these, really. You could go to any asylum cemetery and root around and not be bothered, or hang out at the gallows and scoop up an executed criminal. Those two were pretty easy. Getting the heads of geniuses proved to be considerably more difficult.

Among the genius heads stolen and studied by phrenologists was Joseph Haydn’s.