On this kid's (terrific) blog, I read this brief anecdote shared by Larry King with Esquire recently. King says:
I once asked Stephen Hawking, the smartest guy in the world, what he didn’t understand. He said, "Women."
Great punchline.
My only objection here is that Stephen Hawking didn't say that. He typed it. His text to speech synthesizer said it.
Relatedly, this is my all time favorite photo of Larry King.