Henry Ford was notoriously ill-informed. He sued a newspaper for libel after they said he was an idiot. In the trial they asked him in what year the revolution that founded the country took place. "1812?" facepalm
And yet Ford was a fantastic innovator and worth $188 billion (adjusted for inflation) when he died! It really hammers in the point that general knowledge and intelligence are very different skillsets.
edit: unfortunate typo