Given the chance and opportunities some people WILL change their mind, others, however, are so stubborn that even radical brain surgery will have no effect at all.

I disagree. Maybe Frank just wasn't very persuasive.

Not necessarily. Sure, there are some people who are too stubborn to change their minds. But there are other people who just need to see the evidence more clearly, and they will follow the best evidence wherever it leads. I am, happily, a follower of the evidence. If it were not so, I would still be a Moron (oops, Mormon).