Why do people refuse to vaccinate their children against measles or whooping cough? In many cases, because they have never seen measles and have no idea what it might do.

I have no idea what I'm doin'. I've never seen me.

I've never seen anything like it. I had no idea it could be that bad. I wasn't sure why he didn't want to play in Baltimore, but the people took it personally. I've never seen a player get booed non-stop in pregame warmups. It was brutal.

You walk on a set, and you have no idea - that's why I don't storyboard. It's all possible.

Everyone knows that metaphors are important, yet we have no idea why.

There's no good idea that can't be improved on.