Ehrman, Interrupted

I have an open mind when it comes to looking over Biblical history and was therefore willing to give this guy's theories a read. That is, until reaching this:

He says he doesn't believe the followers of Jesus saw their master bodily rise from the dead, but something else.

"My best guess is that what happened is what commonly happens today when someone has a loved one die -- they sometimes think they see them in a vision," Ehrman says. "I think some of the disciples had visions."

Visions? Shared visions by numerous people? Seems amazing that a guy who's written 20 books can stake his entire ideological claim by simply substituting one unsubstantiated belief for another. Well, surely the doubting Thomases of today want to believe him--in the same way their namesake didn't believe.