And...there IS Dr. Ben Carson. *winces* He IS a brain surgeon. Really. I find it difficult to fathom, myself.
I heard (or read, can't quite remember) an analysis of this fact which was interesting: yes, it takes some brains and skill to do that job, however, he's basically a technician. (I can't really put down technicians in general because that's what I did for a number of years (though my field was electronics). However, now I'm an engineer, and my knowledge and skills have broadened, though I still think of myself as like a junior engineer.) So sure, he's bright in one highly specialized field, but that doesn't imply any level of intelligence in other fields.