Unhuman
From an extended interview, whose quality I can not yet attest to as I have not finished reading it, Billy Joel on Not Working and Not Giving Up Drinking:
Some writers can write reams of great books and then J. D. Salinger wrote just a few. Beethoven wrote nine symphonies. They were all phenomenal. Mozart wrote some 40 symphonies, and they were all phenomenal. That doesn’t mean Beethoven was a lesser writer, it’s just some guys are capable of more productivity, some guys take more time. Mozart pisses me off because he’s like a naturally gifted athlete, you listen to Mozart and you go: “Of course. It all came easy to him.” Beethoven you hear the struggle in it. Look at his manuscripts, and there’s reams of scratched-out music that he hated. He stops and he starts. I love that about Beethoven, his humanity shows in his music. Mozart was almost inhuman, unhuman.
I’ve seen unhuman aptitude up close and it always engenders jealousy. It may be false that Antonio Salieri hated Mozart, but I’m sure other contemporaries did.